METHODS OF TREATING, AMELIORATING, AND/OR PREVENTING

OSTEOARTHRITIC PAIN

CROSS-REFERENCE TO RELATED APPLICATION

This application claims the benefit of priority to U.S. Provisional Patent Application Serial No. 63/211,744 entitled " METHODS OF TREATING, AMELIORATING, AND/OR PREVENTING OSTEOARTHRITIC PAIN," filed June 17, 2021, the disclosure of which is incorporated herein by reference in its entirety.

BACKGROUND

Chronic musculoskeletal pain affects a large proportion of the global population. A significant cause of chronic musculoskeletal pain is due to osteoarthritis (OA). Osteoarthritis is a progressive, chronic disease caused by the breakdown and loss of cartilage of the joints, which leads to pain in the hips, knees, hands, feet, and spine. Symptoms and disability increase with increasing age. The prevalence of OA in patients aged 65 and older is 60% in men and 70% in women, and is continually rising.

Nonsteroidal anti-inflammatory drugs (NSAIDs) are the mainstay of treatment in patients with mild-to-moderate OA. The efficacy of NSAIDs is well documented, albeit modest, while their use is associated with a number of well recognized risks, including gastrointestinal bleeding and increased risk of cardiovascular events. Those with advanced OA pain typically try several NSAIDs and must often escalate to other therapies including opioids as well as a variety of transiently effective intra-articular therapies.

As a chronically progressive disease, many patients progress until their last option is a joint replacement. However, even with surgery, the complete relief of pain or disability is not guaranteed. For the majority of patients worldwide the inadequate pain relief and disability due to OA has a profound impact on the quality of life with an associated loss of productivity, and substantial cost to society, including healthcare cost.

There is thus a need in the medical and patient communities for a new class of therapeutic agents that can relieve pain associated with osteoarthritis. The methods and compounds described herein address this pressing need.

SUMMARY

In various embodiments, a method of treating, ameliorating, and/or preventing osteoarthritic pain in a subject is provided. The method includes administering a therapeutically effective amount of a compound of Formula I: Formula I (Compound 1), to an individual having osteoarthritic pain. In certain embodiments, the compound is formulated as part of a pharmaceutical composition further comprising at least one pharmaceutically acceptable carrier and/or excipient.

BRIEF DESCRIPTION OF THE FIGURES

The drawings illustrate generally, by way of example, but not by way of limitation, various embodiments of the present application.

FIG. 1 depicts a schematic outline of a clinical trial with Compound 1.

DETAILED DESCRIPTION

Reference will now be made in detail to certain embodiments of the disclosed subject matter. While the disclosed subject matter will be described in conjunction with the enumerated claims, it will be understood that the exemplified subject matter is not intended to limit the claims to the disclosed subject matter.

Throughout this document, values expressed in a range format should be interpreted in a flexible manner to include not only the numerical values explicitly recited as the limits of the range, but also to include all the individual numerical values or sub-ranges encompassed within that range as if each numerical value and sub-range is explicitly recited. For example, a range of "about 0.1% to about 5%" or "about 0.1% to 5%" should be interpreted to include not just about 0.1% to about 5%, but also the individual values (e.g., 1%, 2%, 3%, and 4%) and the sub-ranges (e.g., 0.1% to 0.5%, 1.1% to 2.2%, 3.3% to 4.4%) within the indicated range. The statement "about X to Y" has the same meaning as "about X to about Y," unless indicated otherwise. Likewise, the statement "about X, Y, or about Z" has the same meaning as "about X, about Y, or about Z," unless indicated otherwise.

In this document, the terms "a," "an," or "the" are used to include one or more than one unless the context clearly dictates otherwise. The term "or" is used to refer to a nonexclusive "or" unless otherwise indicated. The statement "at least one of A and B" or "at least one of A or B" has the same meaning as "A, B, or A and B." In addition, it is to be understood that the phraseology or terminology employed herein, and not otherwise defined, is for the purpose of description only and not of limitation. Any use of section headings is intended to aid reading of the document and is not to be interpreted as limiting; information that is relevant to a section heading may occur within or outside of that particular section. All publications, patents, and patent documents referred to in this document are incorporated by reference herein in their entirety, as though individually incorporated by reference.

In the methods described herein, the acts can be carried out in any order, except when a temporal or operational sequence is explicitly recited. Furthermore, specified acts can be carried out concurrently unless explicit claim language recites that they be carried out separately. For example, a claimed act of doing X and a claimed act of doing Y can be conducted simultaneously within a single operation, and the resulting process will fall within the literal scope of the claimed process.

Definitions

The term "about" as used herein can allow for a degree of variability in a value or range, for example, within 10%, within 5%, or within 1% of a stated value or of a stated limit of a range, and includes the exact stated value or range.

The term "substantially" as used herein refers to a majority of, or mostly, as in at least about 50%, 60%, 70%, 80%, 90%, 95%, 96%, 97%, 98%, 99%, 99.5%, 99.9%, 99.99%, or at least about 99.999% or more, or 100%. The term "substantially free of as used herein can mean having none or having a trivial amount of, such that the amount of material present does not affect the material properties of the composition including the material, such that the composition is about 0 wt% to about 5 wt% of the material, or about 0 wt% to about 1 wt%, or about 5 wt% or less, or less than, equal to, or greater than about 4.5 wt%, 4, 3.5, 3, 2.5, 2, 1.5, 1, 0.9, 0.8, 0.7, 0.6, 0.5, 0.4, 0.3, 0.2, 0.1, 0.01, or about 0.001 wt% or less. The term "substantially free of can mean having a trivial amount of, such that a composition is about 0 wt% to about 5 wt% of the material, or about 0 wt% to about 1 wt%, or about 5 wt% or less, or less than, equal to, or greater than about 4.5 wt%, 4, 3.5, 3, 2.5, 2, 1.5, 1, 0.9, 0.8, 0.7, 0.6, 0.5, 0.4, 0.3, 0.2, 0.1, 0.01, or about 0.001 wt% or less, or about 0 wt%.

As used herein, the term "composition" or "pharmaceutical composition" refers to a mixture of at least one compound described herein with a pharmaceutically acceptable carrier. The pharmaceutical composition facilitates administration of the compound to a patient or subject. Multiple techniques of administering a compound exist in the art including, but not limited to, intravenous, oral, aerosol, parenteral, ophthalmic, pulmonary and topical administration.

As used therein, "delaying" the development of osteoarthritic pain means to defer, hinder, slow, retard, stabilize, and/or postpone progression of osteoarthritic pain. This delay can be of varying lengths of time, depending on the history of the disease and/or individuals being treated. A method that "delays" development of the symptom is a method that reduces probability of developing the symptom in a given time frame and/or reduces extent of the symptoms in a given time frame, when compared to not using the method.

As used herein, "development" or "progression" of osteoarthritic pain means initial manifestations and/or ensuing progression of the disorder. Development of osteoarthritic pain can be detectable and assessed using standard clinical techniques known in the art. However, development also refers to progression that may be undetectable. As used herein, development or progression refers to the biological course of the symptoms. "Development" includes occurrence, recurrence, and onset. As used herein, "onset" or "occurrence" of osteoarthritic pain includes initial onset and/or recurrence.

A "disease" is a state of health of an animal wherein the animal cannot maintain homeostasis, and wherein if the disease is not ameliorated then the animal's health continues to deteriorate.

In contrast, a "disorder" in an animal is a state of health in which the animal is able to maintain homeostasis, but in which the animal's state of health is less favorable than it would be in the absence of the disorder. Left untreated, a disorder does not necessarily cause a further decrease in the animal's state of health.

As used herein, the terms "effective amount," "pharmaceutically effective amount" and "therapeutically effective amount" refer to a nontoxic but sufficient amount of an agent to provide the desired biological result. That result may be reduction and/or alleviation of the signs, symptoms, or causes of a disease, or any other desired alteration of a biological system. An appropriate therapeutic amount in any individual case may be determined by one of ordinary skill in the art using routine experimentation.

As used herein, the term "efficacy" refers to the maximal effect (Emax) achieved within an assay.

As used herein, "mechanically -induced pain" refers to pain induced by a mechanical stimulus, such as the application of weight to a surface, tactile stimulus, and stimulation caused or associated with movement (including coughing, shifting of weight, and so forth).

As used herein, the term "pharmaceutically acceptable" refers to a material, such as a carrier or diluent, which does not abrogate the biological activity or properties of the compound, and is relatively non-toxic, i.e., the material may be administered to an individual without causing undesirable biological effects or interacting in a deleterious manner with any of the components of the composition in which it is contained.

As used herein, the language "pharmaceutically acceptable salt" refers to a salt of the administered compounds prepared from pharmaceutically acceptable non-toxic acids or bases, including inorganic acids or bases, organic acids or bases, solvates, hydrates, or clathrates thereof.

Suitable pharmaceutically acceptable acid addition salts may be prepared from an inorganic acid or from an organic acid. Examples of inorganic acids include hydrochloric, hydrobromic, hydriodic, nitric, carbonic, sulfuric (including sulfate and hydrogen sulfate), and phosphoric acids (including hydrogen phosphate and dihydrogen phosphate).

Appropriate organic acids may be selected from aliphatic, cycloaliphatic, aromatic, araliphatic, heterocyclic, carboxylic and sulfonic classes of organic acids, examples of which include formic, acetic, propionic, succinic, glycolic, gluconic, lactic, malic, tartaric, citric, ascorbic, glucuronic, maleic, malonic, saccharin, fumaric, pyruvic, aspartic, glutamic, benzoic, anthranilic, 4-hydroxybenzoic, phenylacetic, mandelic, embonic (pamoic), methanesulfonic, ethanesulfonic, benzenesulfonic, pantothenic, trifluoromethanesulfonic, 2- hydroxyethanesulfonic, p-toluenesulfonic, sulfanilic, cyclohexylaminosulfonic, stearic, alginic, b-hydroxybutyric, salicylic, galactaric and galacturonic acid.

Suitable pharmaceutically acceptable base addition salts of compounds described herein include, for example, ammonium salts, metallic salts including alkali metal, alkaline earth metal and transition metal salts such as, for example, calcium, magnesium, potassium, sodium and zinc salts. Pharmaceutically acceptable base addition salts also include organic salts made from basic amines such as, for example, N,N'-dibenzylethylene-diamine, chloroprocaine, choline, diethanolamine, ethylenediamine, meglumine (N-methylglucamine) and procaine. All of these salts may be prepared from the corresponding compound by reacting, for example, the appropriate acid or base with the compound.

As used herein, the term "pharmaceutically acceptable carrier" or "pharmaceutically acceptable excipient" means a pharmaceutically acceptable material, composition or carrier, such as a liquid or solid filler, stabilizer, dispersing agent, suspending agent, diluent, excipient, thickening agent, solvent or encapsulating material, involved in carrying or transporting a compound described herein within or to the patient such that it may perform its intended function. Typically, such constructs are carried or transported from one organ, or portion of the body, to another organ, or portion of the body. Each carrier must be "acceptable" in the sense of being compatible with the other ingredients of the formulation, including the compound(s) described herein, and not injurious to the patient. Some examples of materials that may serve as pharmaceutically acceptable carriers include: sugars, such as lactose, glucose and sucrose; starches, such as com starch and potato starch; cellulose, and its derivatives, such as sodium carboxymethyl cellulose, ethyl cellulose and cellulose acetate; powdered tragacanth; malt; gelatin; talc; excipients, such as cocoa butter and suppository waxes; oils, such as peanut oil, cottonseed oil, safflower oil, sesame oil, olive oil, com oil and soybean oil; glycols, such as propylene glycol; polyols, such as glycerin, sorbitol, mannitol and polyethylene glycol; esters, such as ethyl oleate and ethyl laurate; agar; buffering agents, such as magnesium hydroxide and aluminum hydroxide; surface active agents; alginic acid; pyrogen-free water; isotonic saline; Ringer's solution; ethyl alcohol; phosphate buffer solutions; and other non-toxic compatible substances employed in pharmaceutical formulations. As used herein, "pharmaceutically acceptable carrier" also includes any and all coatings, antibacterial and antifungal agents, and absorption delaying agents, and the like that are compatible with the activity of the compound(s) described herein, and are physiologically acceptable to the patient. Supplementary active compounds may also be incorporated into the compositions. The "pharmaceutically acceptable carrier" may further include a pharmaceutically acceptable salt of the compound(s) described herein. Other additional ingredients that may be included in the pharmaceutical compositions used with the methods or compounds described herein are known in the art and described, for example in Remington's Pharmaceutical Sciences (Genaro, Ed., Mack Publishing Co., 1985, Easton,

PA), which is incorporated herein by reference.

Other pharmaceutically acceptable excipients include, but are not limited to, one or more of the following: excipients; surface active agents; dispersing agents; inert diluents; granulating and disintegrating agents; binding agents; lubricating agents; sweetening agents; flavoring agents; coloring agents; preservatives; physiologically degradable compositions such as gelatin; aqueous vehicles and solvents; oily vehicles and solvents; suspending agents; dispersing or wetting agents; emulsifying agents, demulcents; buffers; salts; thickening agents; fillers; emulsifying agents; antioxidants; antibiotics; antifungal agents; stabilizing agents; and pharmaceutically acceptable polymeric or hydrophobic materials. Other "additional ingredients" which may be included in the pharmaceutical compositions of the compound(s) described herein are known in the art and described, for example in Genaro, ed. 1985, Remington's Pharmaceutical Sciences, Mack Publishing Co., Easton, PA, which is incorporated herein by reference. The terms "patient," "subject," or "individual" are used interchangeably herein, and refer to any animal, or cells thereof whether in vitro or in situ, amenable to the methods described herein. In a non-limiting embodiment, the patient, subject or individual is a human. The term "individual" as used herein, also refers to an individual or a subject, a patient or a person in need of relief of pain, or a human volunteer willing to be administered a therapeutic agent.

As used herein, "osteoarthritic pain," refers to pain arising or resulting from osteoarthritis (OA) in one or more tissues or joints in a patient's body. As used herein, "pain" includes nociception and the sensation of pain, and pain can be assessed objectively and/or subjectively, using pain scores and other methods well-known in the art. Pain can be thermal or mechanical (tactile) in nature. In various embodiments, the pain is characterized by thermal (hot or cold) sensitivity, mechanical sensitivity and/or resting pain. In various embodiments, the osteoarthritic pain includes mechanically-induced pain or resting pain. In other embodiments, the osteoarthritic pain includes resting pain. The pain can be primary or secondary pain.

As used herein, the term "potency" refers to the dose needed to produce a desired effect such as reduction or elimination of pain. One measure of potency is the dose needed to produ ce half of the maximal response (ED50) or a dose needed to produce a percent of the maximal effect (%MPE) such as 50%MPE (the ED50), 90%MPE or 100%MPE (full efficacy)

As used herein, "reducing incidence" of pain means any of reducing severity (which can include reducing need for and/or amount of (e.g., exposure to) other drugs and/or therapies generally used for this conditions, including, for example, opiates (opioids), NSAIDs (non steroidal anti-inflammatory drugs) and ion channel blockers), decreasing duration, and/or frequency (including, for example, delaying or increasing time to osteoarthritic pain in an individual). Since a patient's response to a treatment can vary, reducing incidence in the context of pain also means that there is a reasonable expectation by person of skill in the art that administration of Compound 1 is likely to result in a reduction in incidence of pain in a particular individual.

As used herein, "resting pain" refers to pain occurring even while the individual is at rest as opposed to, for example, pain occurring when the individual moves or is subjected to other mechanical stimuli (e.g., being moved in bed or out of bed, being helped to the bathroom, being moved in or out of a wheelchair, and the like).

A "therapeutic" treatment is a treatment administered to a subject who exhibits signs of pathology, for the purpose of diminishing or eliminating those signs. As used herein, the term "treatment" or "treating" is defined as the application or administration of a therapeutic agent, i.e., a compound or compounds described herein (alone or in combination with another pharmaceutical agent), to a patient, or application or administration of a therapeutic agent to an isolated tissue or cell line from a patient (e.g., for diagnosis or ex vivo applications), who has a condition contemplated herein, a symptom of a condition contemplated herein or the potential to develop a condition contemplated herein, with the purpose to cure, heal, alleviate, relieve, alter, remedy, ameliorate, improve, or affect a condition contemplated herein, the symptoms of a condition contemplated herein or the potential to develop a condition contemplated herein. Such treatments may be specifically tailored or modified, based on knowledge obtained from the field of pharmacogenomics. Ameliorating osteoarthritic pain or one or more symptoms of osteoarthritis means a lessening or improvement of one or more symptoms of osteoarthritic pain after administration of Compound 1 as compared to not administering Compound 1, and also includes shortening or reduction in duration of a symptom.

Symptoms of osteoarthritis that can be treated or ameliorated by administration of compounds of the disclosure include, but are not limited to, stiffness in the joints, tenderness in or around a joint, loss of flexibility, grating sensation in the joint, pain from bone spurs in the joint, and swelling.

The following abbreviations are used herein: ASR, accurate symptom reporting; BBn, boron tribromide; BPI-sf, Brief Pain Inventory-Short Form; CD3OD, (tetra)deuterio- methanol; CBC, complete blood count; CHEM, clinical chemistry serum tests; COVID-19, coronavirus disease 2019; C- SSRS, Columbia-Suicide Severity Rating Scale; COX, cyclooxygenase; d, day(s); DMSO, dimethylsulfoxide; DSC, differential scanning calorimetry; ECG, electrocardiogram; eDiary, electronic diary; ELSD, evaporative light- scattering detection; EOT, end of treatment; ET, early termination; g, gram; GC, gas chromatography; GC-MS, gas chromatography -mass spectrometry; GVS, gravimetric vapor sorption; h, hour(s); HADS, Hospital Anxiety and Depression Scale; HC1, hydrochloric acid; HPLC, high performance liquid chromatography; ICH, International Conference on Harmonisation; iPrOH, isopropanol; IR, infrared (spectrum); mg, milligram; min, minute(s); mL, milliliter; mol, mole; mmol, millimole; MTBE, methyl /e/V-butyl ether; NADPH, dihydronicotinamide-adenine dinucleotide phosphate; NaOH, sodium hydroxide; ng, nanogram; NLT, not less than; NMR, nuclear magnetic resonance; NMT, not more than; NOS, nitric oxide synthase; NSAID, non-steroidal anti-inflammatory drug; PGIC, Patient Global Impression of Change; pKa, negative base- 10 logarithm of the acid dissociated constant; PK, pharmacokinetic; PN, peroxynitrite; PRR, placebo response reduction; RNS, reactive nitrogen species; ROI, residue on ignition; ROS, reactive oxygen species; SF-12, 12- item Short Form Survey; TRP, Transient-Receptor Potential; UA, urinalysis; USP, United States Pharmacopeia; UV, ultraviolet; XRPD, x-ray (powder) diffraction pattern.

Preparation of Compounds

The compound of Formula (I) can be prepared by the general schemes described herein, using the synthetic method known by those skilled in the art. The following examples illustrate non-limiting embodiments of the compound(s) described herein and their preparation.

The compounds described herein, and other related compounds having different substituents are synthesized using techniques and materials described herein and as described, for example, in Fieser & Fieser's Reagents for Organic Synthesis, Volumes 1-17 (John Wiley and Sons, 1991); Rodd's Chemistry of Carbon Compounds, Volumes 1-5 and Supplemental (Elsevier Science Publishers, 1989); Organic Reactions, Volumes 1-40 (John Wiley and Sons, 1991), Larock's Comprehensive Organic Transformations (VCH Publishers Inc., 1989), March, Advanced Organic Chemistry 4 ^th Ed., (Wiley 1992); Carey & Sundberg, Advanced Organic Chemistry 4th Ed., Vols. A and B (Plenum 2000,2001), and Green & Wuts, Protective Groups in Organic Synthesis 3rd Ed., (Wiley 1999) (all of which are incorporated by reference for such disclosure). General methods for the preparation of compound as described herein are modified by the use of appropriate reagents and conditions, for the introduction of the various moieties found in the formula as provided herein.

Compounds described herein are synthesized using any suitable procedures starting from compounds that are available from commercial sources, or are prepared using procedures described herein.

In certain embodiments, reactive functional groups, such as hydroxyl, amino, imino, thio or carboxy groups, are protected in order to avoid their unwanted participation in reactions. Protecting groups are used to block some or all of the reactive moieties and prevent such groups from participating in chemical reactions until the protective group is removed. In other embodiments, each protective group is removable by a different means. Protective groups that are cleaved under totally disparate reaction conditions fulfill the requirement of differential removal.

In certain embodiments, protective groups are removed by acid, base, reducing conditions (such as, for example, hydrogenolysis), and/or oxidative conditions. Groups such as trityl, dimethoxytrityl, acetal and t-butyldimethylsilyl are acid labile and are used to protect carboxy and hydroxy reactive moieties in the presence of amino groups protected with Cbz groups, which are removable by hydrogenolysis, and Fmoc groups, which are base labile. Carboxylic acid and hydroxy reactive moieties are blocked with base labile groups such as, but not limited to, methyl, ethyl, and acetyl, in the presence of amines that are blocked with acid labile groups, such as t-butyl carbamate, or with carbamates that are both acid and base stable but hydrolytically removable.

In certain embodiments, carboxylic acid and hydroxy reactive moieties are blocked with hydrolytically removable protective groups such as the benzyl group, while amine groups capable of hydrogen bonding with acids are blocked with base labile groups such as Fmoc. Carboxylic acid reactive moieties are protected by conversion to simple ester compounds as exemplified herein, which include conversion to alkyl esters, or are blocked with oxidatively -removable protective groups such as 2,4-dimethoxybenzyl, while co existing amino groups are blocked with fluoride labile silyl carbamates.

Allyl blocking groups are useful in the presence of acid- and base- protecting groups since the former are stable and are subsequently removed by metal or pi-acid catalysts. For example, an allyl-blocked carboxylic acid is deprotected with a palladium-catalyzed reaction in the presence of acid labile t-butyl carbamate or base-labile acetate amine protecting groups. Yet another form of protecting group is a resin to which a compound or intermediate is attached. As long as the residue is attached to the resin, that functional group is blocked and does not react. Once released from the resin, the functional group is available to react.

Typically blocking/protecting groups may be selected from: allyl, benzyl, benzyloxy carbonyl (Cbz), allyloxy carbonyl (alloc), methyl, ethyl, t-butyl, t- butyldimethylsylyl (TBDMS), Teoc, Boc, para-methoxy benzyl (PMB), trityl, acetyl, and Fmoc.

Other protecting groups, plus a detailed description of techniques applicable to the creation of protecting groups and their removal are described in Greene & Wuts, Protective Groups in Organic Synthesis, 3rd Ed., John Wiley & Sons, New York, NY, 1999, and Kocienski, Protective Groups, Thieme Verlag, New York, NY, 1994, which are incorporated herein by reference for such disclosure.

Compositions

Compositions containing Compound 1 described herein include a pharmaceutical composition containing Compound 1 and at least one pharmaceutically acceptable excipient and/or carrier. In certain embodiments, the composition is formulated for an administration route such as oral or parenteral, for example, transdermal, transmucosal (e.g., sublingual, lingual, (trans)buccal, (trans)urethral, vaginal (e.g., trans- and perivaginally), (intra)nasal and (trans)rectal, intravesical, intrapulmonary, intraduodenal, intragastrical, intrathecal, subcutaneous, intramuscular, intradermal, intra-arterial, intravenous, intrabronchial, inhalation, and topical administration.

In various embodiments, a pharmaceutical composition of Compound 1 includes

HCI

Formula I (Compound 1), and about 0.0001 % to about 0.30% w/w of at least one impurity selected from the group consisting of 2-Cl-BO, BO-Imp-1, BO-Imp-2, BO-Imp-3, BO-Imp-4, BO-Imp-5, and Cmpl Imp-3. The pharmaceutical composition can also include at least one pharmaceutically acceptable excipient and/or carrier, as described herein.

In various embodiments, the composition can include at least one pharmaceutically acceptable carrier and/or at least one pharmaceutically acceptable excipient, including any of the pharmaceutically acceptable carriers or excipients described herein. Pharmaceutically acceptable carriers, which are useful, include, but are not limited to, glycerol, water, saline, ethanol and other pharmaceutically acceptable salt solutions such as phosphates and salts of organic acids. Examples of these and other pharmaceutically acceptable carriers are described in Remington's Pharmaceutical Sciences, 18 ^th Edition (1990, Mack Publication Co., New Jersey).

The composition can be prepared, packaged, or sold in the form of a sterile injectable aqueous or oily suspension or solution. This suspension or solution may be formulated according to the known art, and may comprise, in addition to the active ingredient, additional ingredients such as anti-oxidants, dispersing agents, wetting agents, or suspending agents described herein. Such sterile injectable formulations may be prepared using a non-toxic parenterally-acceptable diluent or solvent, such as water or 1,3-butane diol, for example. Other acceptable diluents and solvents include, but are not limited to, Ringer's solution, isotonic sodium chloride solution, and fixed oils such as synthetic mono- or di-glycerides.

Compositions that are useful in the methods described herein can be administered, prepared, packaged, and/or sold in formulations suitable for intravenous, subcutaneous, sublingual, oral, rectal, vaginal, parenteral, topical, pulmonary, intranasal, buccal, ophthalmic, or another route of administration. Other contemplated formulations include projected nanoparticles, liposomal preparations, resealed erythrocytes containing the active ingredient, and immunologically -based formulations.

The compositions can be administered via numerous routes, including, but not limited to, intravenous, subcutaneous, sublingual, oral, rectal, vaginal, parenteral, topical, pulmonary, intranasal, buccal, or ophthalmic administration routes. The route(s) of administration will be readily apparent to the skilled artisan and will depend upon any number of factors including the type and severity of the disorder being treated, the type and age of the veterinary or human patient being treated, and the like.

Compositions that are useful in the methods described herein can be administered systemically in intravenous and subcutaneous liquid formulations, oral and sublingual solid formulations, ophthalmic, suppository, aerosol, topical or other similar formulations. In addition to the compound such as heparin sulfate, or a biological equivalent thereof, such pharmaceutical compositions may contain pharmaceutically-acceptable carriers and other ingredients known to enhance and facilitate drug administration. Other possible formulations, such as nanoparticles, liposomes, resealed erythrocytes, and immunologically based systems may also be used to administer compounds according to the methods as described herein.

The formulations of the compositions described herein can be prepared by any method known or hereafter developed in the art of pharmacology. In general, such preparatory methods include the step of bringing the active ingredient (e.g., Compound 1) into association with a carrier or one or more other accessory ingredients, and then, if necessary or desirable, shaping or packaging the product into a desired single- or multi-dose unit.

Although the descriptions of compositions provided herein are principally directed to pharmaceutical compositions which are suitable for ethical administration to humans, it will be understood by the skilled artisan that such compositions are generally suitable for administration to subjects of all sorts.

Modification of compositions suitable for administration to humans in order to render the compositions suitable for administration to various animals is well understood, and the ordinarily skilled veterinary pharmacologist can design and perform such modification with merely ordinary, if any, experimentation. Subjects to which administration of the compositions described herein are contemplated include, but are not limited to, humans and other primates, mammals including commercially relevant mammals such as cattle, pigs, horses, sheep, cats, and dogs.

Compositions that are useful in the methods described herein can be prepared, packaged, or sold in formulations suitable for intravenous, subcutaneous, sublingual, oral, rectal, vaginal, parenteral, topical, pulmonary, intranasal, buccal, ophthalmic, intrathecal or another route of administration. Other contemplated formulations include projected nanoparticles, liposomal preparations, resealed erythrocytes containing the active ingredient, and immunologically based formulations.

A composition for use in the methods described herein can be prepared, packaged, or sold in bulk, as a single unit dose, or as a plurality of single unit doses. As used herein, a "unit dose" is a discrete amount of the pharmaceutical composition comprising a predetermined amount of the active ingredient. The amount of the active ingredient is generally equal to the dosage of the active ingredient that would be administered to a subject or a convenient fraction of such a dosage such as, for example, one-half or one-third of such a dosage.

The relative amounts of the active ingredient (e.g., Compound 1), the pharmaceutically acceptable carrier, and any additional ingredients in a pharmaceutical composition described herein will vary, depending upon the identity, size, and condition of the subject treated and further depending upon the route by which the composition is to be administered. By way of example, the composition may comprise between 0.1% and 100% (w/w) active ingredient.

Liquid derivatives and natural extracts made directly from biological sources may be employed in the compositions described herein in a concentration (w/v) from about 1 to about 99%. Fractions of natural extracts and protease inhibitors may have a different preferred range, from about 0.01% to about 20% and, more preferably, from about 1% to about 10% of the composition. Of course, mixtures of the active agents described herein can be combined and used together in the same formulation, or in serial applications of different formulations.

The compositions described herein can include a preservative from about 0.005% to 2.0% by total weight of the composition. The preservative is used to prevent spoilage in the case of an aqueous gel because of repeated patient use when it is exposed to contaminants in the environment from, for example, exposure to air or the patient's skin, including contact with the fingers used for applying a composition described herein such as a therapeutic gel or cream. Examples of preservatives useful in accordance with the compound(s) described herein include but are not limited to those selected from the group consisting of benzyl alcohol, sorbic acid, parabens, imidurea and combinations thereof. A particularly preferred preservative is a combination of about 0.5% to 2.0% benzyl alcohol and 0.05% to 0.5% sorbic acid.

The composition can include an antioxidant and a chelating agent which can inhibit any the degradation of Compound 1 that may occur, for use in an aqueous gel formulation. Suitable antioxidants include BHT, BHA, a-tocopherol and ascorbic acid in the non-limiting range of about 0.01% to 0.3% and more preferably BHT in the range of 0.03% to 0.1% by weight by total weight of the composition. The chelating agent can be present in an amount of from 0.01% to 0.5% by weight by total weight of the composition. Non-limiting chelating agents include edetate salts ( e.g . disodium edetate) and citric acid in the weight range of about 0.01% to 0.20% and for example in the range of 0.02% to 0.10% by weight by total weight of the composition. The chelating agent is useful for chelating metal ions in the composition which may be detrimental to the shelf life of the formulation. While BHT and disodium edetate are the particularly preferred antioxidant and chelating agent respectively for some compounds, other suitable and equivalent antioxidants and chelating agents may be substituted therefore as would be known to those skilled in the art.

Liquid suspensions may be prepared using conventional methods to achieve suspension of the active ingredient in an aqueous or oily vehicle. Aqueous vehicles include, for example, water, and isotonic saline. Oily vehicles include, for example, almond oil, oily esters, ethyl alcohol, vegetable oils such as arachis, olive, sesame, or coconut oil, fractionated vegetable oils, and mineral oils such as liquid paraffin. Liquid suspensions may further comprise one or more additional ingredients including, but not limited to, suspending agents, dispersing or wetting agents, emulsifying agents, demulcents, preservatives, buffers, salts, flavorings, coloring agents, and sweetening agents. Oily suspensions may further comprise a thickening agent. Known suspending agents include, but are not limited to, sorbitol syrup, hydrogenated edible fats, sodium alginate, polyvinylpyrrolidone, gum tragacanth, gum acacia, and cellulose derivatives such as sodium carboxymethylcellulose, methylcellulose, hydroxypropylmethylcellulose.

Suitable dispersing or wetting agents include, but are not limited to, naturally-occurring phosphatides such as lecithin, condensation products of an alkylene oxide with a fatty acid, with a long chain aliphatic alcohol, with a partial ester derived from a fatty acid and a hexitol, or with a partial ester derived from a fatty acid and a hexitol anhydride (e.g., polyoxyethylene stearate, heptadecaethyleneoxycetanol, polyoxyethylene sorbitol monooleate, and polyoxyethylene sorbitan monooleate, respectively). Suitable emulsifying agents include, but are not limited to, lecithin, and acacia. Suitable preservatives include, but are not limited to, methyl, ethyl, or n-propyl-para-hydroxybenzoates, ascorbic acid, and sorbic acid. Suitable sweetening agents include, for example, glycerol, propylene glycol, sorbitol, sucrose, and saccharin. Suitable thickening agents for oily suspensions include, for example, beeswax, hard paraffin, and cetyl alcohol.

Liquid solutions of the active ingredient in aqueous or oily solvents may be prepared in substantially the same manner as liquid suspensions, the primary difference being that the active ingredient is dissolved, rather than suspended in the solvent. Liquid solutions of the pharmaceutical composition(s) described herein can comprise each of the components described with regard to liquid suspensions, it being understood that suspending agents will not necessarily aid dissolution of the active ingredient in the solvent. Aqueous solvents include, for example, water, and isotonic saline. Oily solvents include, for example, almond oil, oily esters, ethyl alcohol, vegetable oils such as arachis, olive, sesame, or coconut oil, fractionated vegetable oils, and mineral oils such as liquid paraffin.

Powdered and granular formulations of a pharmaceutical preparation(s) described herein can be prepared using known methods. Such formulations may be administered directly to a subject, used, for example, to form tablets, to fill capsules, or to prepare an aqueous or oily suspension or solution by addition of an aqueous or oily vehicle thereto.

Each of these formulations may further comprise one or more of dispersing or wetting agent, a suspending agent, and a preservative. Additional excipients, such as fillers and sweetening, flavoring, or coloring agents, may also be included in these formulations.

The composition described herein can also be prepared, packaged, or sold in the form of oil-in-water emulsion or a water-in-oil emulsion. The oily phase may be a vegetable oil such as olive or arachis oil, a mineral oil such as liquid paraffin, or a combination of these. Such compositions may further comprise one or more emulsifying agents such as naturally occurring gums such as gum acacia or gum tragacanth, naturally-occurring phosphatides such as soybean or lecithin phosphatide, esters or partial esters derived from combinations of fatty acids and hexitol anhydrides such as sorbitan monooleate, and condensation products of such partial esters with ethylene oxide such as polyoxyethylene sorbitan monooleate. These emulsions may also contain additional ingredients including, for example, sweetening or flavoring agents.

As used herein, an "oily" liquid is one which comprises a carbon-containing liquid molecule and which exhibits a less polar character than water.

A formulation of the compositions described herein suitable for oral administration can be prepared, packaged, or sold in the form of a discrete solid dose unit including, but not limited to, a tablet, a hard or soft capsule, a cachet, a troche, or a lozenge, each containing a predetermined amount of the active ingredient. Other formulations suitable for oral administration include, but are not limited to, a powdered or granular formulation, an aqueous or oily suspension, an aqueous or oily solution, a paste, a gel, toothpaste, a mouthwash, a coating, an oral rinse, or an emulsion. The terms oral rinse and mouthwash are used interchangeably herein.

Methods for impregnating or coating a material with a chemical composition are known in the art, and include, but are not limited to methods of depositing or binding a chemical composition onto a surface, methods of incorporating a chemical composition into the structure of a material during the synthesis of the material (i.e., such as with a physiologically degradable material), and methods of absorbing an aqueous or oily solution or suspension into an absorbent material, with or without subsequent drying.

Compositions described herein can be prepared, packaged, or sold in a formulation suitable for buccal administration. Such formulations may, for example, be in the form of tablets or lozenges made using conventional methods, and may, for example, 0.1 to 20% (w/w) active ingredient, the balance comprising an orally dissolvable or degradable composition and, optionally, one or more of the additional ingredients described herein. Alternately, formulations suitable for buccal administration may include a powder or an aerosolized or atomized solution or suspension including the active ingredient. Such powdered, aerosolized, or aerosolized formulations, when dispersed, preferably have an average particle or droplet size in the range from about 0.1 to about 200 nanometers, and may further comprise one or more of the additional ingredients described herein.

Typically, dosages of the compositions described herein can be administered to a subject, preferably a human, will vary depending upon any number of factors, including but not limited to, the type of animal and type of disease state being treated, the age of the subject and the route of administration.

Physical Properties of Compound 1

Compound 1, (7/)-2-(2-hydro\y pheny lamino)-5.5 -dimethyl -4.5-dihydrothiazole-4- carboxylic acid mono-hydrochloride, has the structure of Formula I:

Formula I (Compound 1).

Compound 1 has the following pKa values: 2.29 ± 0.02 (Acidic), 6.97 ± 0.01 (Basic), and 10.24 ± 0.03 (Acidic). Compound 1 is freely soluble in methanol and /er/-butyl alcohol: water (1:1). Compound 1 is sparingly soluble in Ao-propanol, ethanol, 10% water: /.sopropyl acetate, 10% water/ tetrahydrofuran, and water. Compound 1 is less than sparingly soluble in «-heptane, toluene, acetone, tetrahydrofuran, ethyl acetate, Aopropyl acetate, /er/-butyl methyl ether, and tert- butyl alcohol.

Compound 1 has a LogD distribution coefficient at pH 7.2 of -0.07 (3 mL PBS Buffer: 1 mL Octanol) and -0.39 (2 mL PBS Buffer: 2 mL Octanol), where PBS is phosphate buffer solution.

Impurities in Compositions of Compound 1

In various embodiments, compositions containing Compound 1 described herein can include up to about 0.30% w/w of one or more impurities set forth in Table 1 below.

Table 1: Impurities in Compound 1

In various embodiments, Compound 1 or a composition containing Compound 1 has less than about 0.30 % w/w, 0.25% w/w, 0.20% w/w, or 0.15% w/w of at least one impurity selected from the group consisting of 2-Cl-BO, BO-Imp-1, BO-Imp-2, BO-Imp-3, BO-Imp-4, BO-Imp-5, and Cmpl Imp-3. In various embodiments, Compound 1 or a composition containing Compound 1 has about 0.0001 % to about 0.30% w/w, about 0.0001 % to about 0.25% w/w, about 0.0001 % to about 0.20% w/w, about 0.001% to about 0.15% w/w, or about 0.01% to about 0.15% w/w of at least one impurity selected from the group consisting of 2-Cl-BO, BO-Imp-1, BO-Imp-2, BO-Imp-3, BO-Imp-4, BO-Imp-5, and Cmpl Imp-3. In various embodiments, Compound 1 or a composition containing Compound 1 has about 0.0005%, 0.001%, 0.002%, 0.003%, 0.004%, 0.005%, 0.006%, 0.007%, 0.008%, 0.009%, 0.010%, 0.012%, 0.014%, 0.016%, 0.018%, 0.020%, 0.022%, 0.024%, 0.026%, 0.028%, 0.030%, 0.032%, 0.034%, 0.036%, 0.038%, 0.040%, 0.042%, 0.044%, 0.046%, 0.048%, or 0.050% w/w of at least one impurity selected from the group consisting of 2-C1- BO, BO-Imp-1, BO-Imp-2, BO-Imp-3, BO-Imp-4, BO-Imp-5, and Cmpl Imp-3. In various embodiments, Compound 1 or a composition containing Compound 1 includes about 0.010% to about 0.020% w/w of impurity BO-Imp-1 and about 0.002% to about 0.004% w/w of impurity BO-Imp-5. In various embodiments, one or more of the impurities in Compound 1 described herein are present in isolated Compound 1 in the amounts described herein. A purified Compound 1 is a quantity of Compound 1 that was subjected to one or more of any of the analytical purification techniques described herein, or other purification techniques known in the art.

In various embodiments, a composition containing Compound 1 has about 0.0001 % to about 0.004% w/w, relative to the weight of Compound 1 in the composition, of each of: 2- Cl-BO (2-Chlorobenzoxazole), BO-Imp-3 (2-Aminophenol), and BO-Imp-4 (2-[Bis(l,3- benzoxazol-2-yl) amino] phenol).

Impurities BO-Imp-1 through BO-Imp-5 can arise from the 2-chlorobenzoxazole starting material. BO-Imp-3 is a process impurity which forms by hydrolysis of 2- chlorobenzoxazole by a minor competitive reaction pathway with sodium hydroxide. It can be purged by filtration of the zwitterion of Compound 1. BO-Imp-3 can form as a minor impurity (0.3%) during forced degradation testing of Compound 1, such with 5N sodium hydroxide heating for 5 h.

Cmpl Imp-3 is a process impurity that forms via acid catalyzed esterification of salt- free Compound 1 with /. -propanol solvent during the hydrochloride salt formation. Its formation can be minimized by using stoichiometric hydrogen chloride in /.sopropanol. which is added to a pre-cooled suspension of the zwitterion of Compound 1 in /.so- propanol.

It can be purged by filtration of Compound 1.

The enantiomer of Compound 1 is CS')-2-(2-hy droxy phenylamino)-5.5-di methyl -4.5- dihydrothiazole-4-carboxylic acid mono-hydrochloride, and can be designated fS')-Com pound 1. In various embodiments, the enantiomeric purity of Compound 1 can be at least about

95%, 97%, 98%, 99%, 99.2%, 99.4%, 99.6%, 98.8%, 99.9%, 99.99%, or more. Thus, for example, if the enantiomeric purity of Compound 1 is 99.5%, the composition contains 99.5% Compound 1 and 0.5% fY)-Compound 1. The enantiomeric purity refers only to the relative amounts of Compound 1 and fY)-Compound 1, and additional impurities may be present as described herein.

Methods of Treatment

In various embodiments, a method of treating, ameliorating, and/or preventing osteoarthritic pain, or symptoms associated with osteoarthritis, is provided. The method includes administering a therapeutically effective amount of a composition that includes a compound of Formula I:

" HCi

Formula I (Compound 1), to an individual having osteoarthritic pain or having a symptom associated with osteoarthritis. Although Compound 1 is crystalline, the amorphous form of Compound 1 can also be used in the method of treating osteoarthritic pain described herein. In various embodiments, Compound 1 is the only pharmaceutically active agent in the composition. Additionally, a mixture of crystalline Compound 1 and amorphous Compound 1, in any proportions, can also be used in the method of treating osteoarthritic pain described herein. In various embodiments, the composition includes a therapeutically effective amount of a racemic mixture of Compound 1. A racemic mixture of Compound 1 contains about 50% Compound 1 and about 50% (Aj-Compound 1.

Compound 1 is a non-metal based, orally bioavailable, small molecule reactive species decomposition accelerant (RSDAx) with minimal brain distribution that works by accelerating the degradation of peroxynitrite (PN) and peroxide. Peroxynitrite and peroxide are powerful oxidants produced under conditions of injury (e.g., surgical incision) and disease (e.g., diabetes and osteoarthritis pain) that cause untoward effects via protein nitration, release of pro-inflammatory mediators, and modification of sensory ion channels leading to neuronal sensitization and pain. In vivo, Compound 1 is efficacious in acute animal models of hyperalgesia and allodynia including the chronic pain condition such as OA pain. In a rat OA pain model (mono- iodoacetate [MIA] -induced), Compound 1 significantly reduced mechanical hyperalgesia for at least 24 hours post-dose.

The method described herein can be used to treat, ameliorate, and/or prevent osteoarthritic pain, as well as symptoms associated with osteoarthritis such as stiffness in the joints, tenderness in or around a joint, loss of flexibility, grating sensation in the joint, pain from bone spurs in the joint, swelling, and the like. In various embodiments, a joint can be a point where bones connect and/or two or more bones imbedded in tendons but not connected to other bones (such as a kneecap). Generally, there are three types of joints in the human body.

An immovable joint (synathroses) is a fixed or fibrous joint, such as the bones of the skill, which are also known as sutures. Synathroses include two or more bones in close contact with each other and do not move. A moderately or slightly moveable joint (amphiathroses) is also known as a cartilaginous joint, and includes two or bones held sufficiently tightly together that only limited movement can take place, for example, spinal vertebrae. Finally, a freely moveable joint (diarthroses), which is also known as a synovial joint, allows for all parts of the joint to move freely. Synovial joints include, but are not limited to, the knee and shoulder joints.

In various embodiments, the composition is administered once, twice, three, or four times per day. In various embodiments, the osteoarthritic pain is in or near at least one joint in the subject. In various embodiments, the joint is at least one of a fixed joint, a cartilaginous joint, or a synovial joint. In various embodiments, the joint is at least one of a suture, vertebral, knee, shoulder, hip, elbow, finger, jaw, trochoid, plane, or saddle joint. In various embodiments, the joint is a knee joint.

In various embodiments, a method of treating, ameliorating, and/or preventing osteoarthritic pain or symptoms of osteoarthritis in a subject is provided. The method includes: administering to a subject suffering from osteoarthritic pain or symptoms of osteoarthritis a unit dose composition comprising about 400 to about 1600 mg of a compound of Formula I and at least one pharmaceutically acceptable excipient or carrier:

Formula I (Compound 1), wherein the composition is administered once, twice, thrice, or four times per day and wherein the total daily dose of Compound 1 does not exceed 1600 mg.

In various embodiments, the unit dose composition contains 400 mg of Compound 1 and is administered four times daily. In various embodiments, the unit dose composition includes 800 mg of Compound 1 and is administered twice daily.

Diagnosis or assessment of pain is well-established in the art. Assessment may be performed based on an objective and/or subjective measure, such as observation of behavior such as reaction to stimuli, facial expressions, and the like. Assessment may also be based on subjective measures, such as patient characterization of pain using various pain scales. See, e.g., Katz et al, Surg Clin North Am. (1999) 79 (2):231-52; Caraceni etal., J Pain Symptom Manage (2002) 23(3):239-55.

Pain relief can be characterized by time course of relief. Accordingly, in some embodiments, pain relief is subjectively or objectively observed after at least, greater than, or less than about 5 min, 10 min, 15 min, 20 min, 25 min, 30 min, 35 min, 40 min, 45 min, 50 min, 55 min, 60 min, 1 h, 2 h, 3 h, 4 h, 5 h, 6 h, 7 h, 8 h, 9 h, 10 h, 11 h, 12 h, 13 h, 14 h, 15 h, 16 h, 17 h, 18 h, 19 h, 20 h, 21 h, 22 h, 23 h, or 24 h. Dosing and Dosing Regimens for Treatment of Osteoarthritic Pain

In various embodiments, the therapeutically effective amount of Compound 1 for treating, ameliorating, and/or preventing osteoarthritic pain, or symptoms of osteoarthritis, is from about 5 mg to about 5000 mg. The therapeutically effective amount of Compound 1 can be about 10 mg to about 4750 mg, about 25 mg to about 4500 mg, about 50 mg to about 4250 mg, about 100 mg to about 4000 mg, about 150 mg to about 3750 mg, about 200 mg to about 3500 mg, about 275 mg to about 3250 mg, or about 100 mg to about 3000 mg, about 200 mg to about 2000 mg, about 400 mg to about 1600 mg, about 400 mg to about 1000 mg, about 100 mg to about 900 mg, about 100 mg to about 800 mg, about 150 mg to about 800 mg, about 200 mg to about 800 mg, or about 400 mg to 800 mg. In various embodiments, the therapeutically effective amount of Compound 1 is at least, equal to, or greater than about 5, 10, 20, 40, 60, 80, 100, 120, 140, 160, 180, 200, 220, 240, 260, 280, 300, 320, 340, 360, 380, 400, 420, 440, 460, 480, 500, 600, 750, 800, 900, 1000, 1250, 1500, 1750, 2000, 2500, or about 3000 mg.

In various embodiments, the therapeutically effective amount of Compound 1 for treating, ameliorating, and/or preventing osteoarthritic pain, or symptoms of osteoarthritis, is at least, equal to, or greater than about 100, 105, 110, 115, 120, 125, 130, 135, 140, 145, 150, 155, 160, 165, 170, 175, 180, 185, 190, 195, 200, 205, 210, 215, 220, 225, 230, 235, 240,

245, 250, 255, 260, 265, 270, 275, 280, 285, 290, 295, 300, 305, 310, 315, 320, 325, 330,

335, 340, 345, 350, 355, 360, 365, 370, 375, 380, 385, 390, 395, 400, 405, 410, 415, 420,

425, 430, 435, 440, 445, 450, 455, 460, 465, 470, 475, 480, 485, 490, 495, 500, 505, 510,

515, 520, 525, 530, 535, 540, 545, 550, 555, 560, 565, 570, 575, 580, 585, 590, 595, 600,

605, 610, 615, 620, 625, 630, 635, 640, 645, 650, 655, 660, 665, 670, 675, 680, 685, 690,

695, 700, 705, 710, 715, 720, 725, 730, 735, 740, 745, 750, 755, 760, 765, 770, 775, 780,

785, 790, 795, 800, 805, 810, 815, 820, 825, 830, 835, 840, 845, 850, 855, 860, 865, 870,

875, 880, 885, 890, 895, 900, 905, 910, 915, 920, 925, 930, 935, 940, 945, 950, 955, 960,

965, 970, 975, 980, 985, 990, 995, 1000, 1005, 1010, 1015, 1020, 1025, 1030, 1035, 1040, 1045, 1050, 1055, 1060, 1065, 1070, 1075, 1080, 1085, 1090, 1095, 1100, 1105, 1110, 1115,

1120, 1125, 1130, 1135, 1140, 1145, 1150, 1155, 1160, 1165, 1170, 1175, 1180, 1185, 1190,

1195, 1200, 1205, 1210, 1215, 1220, 1225, 1230, 1235, 1240, 1245, 1250, 1255, 1260, 1265,

1270, 1275, 1280, 1285, 1290, 1295, 1300, 1305, 1310, 1315, 1320, 1325, 1330, 1335, 1340,

1345, 1350, 1355, 1360, 1365, 1370, 1375, 1380, 1385, 1390, 1395, 1400, 1405, 1410, 1415,

1420, 1425, 1430, 1435, 1440, 1445, 1450, 1455, 1460, 1465, 1470, 1475, 1480, 1485, 1490,

1495, 1500, 1505, 1510, 1515, 1520, 1525, 1530, 1535, 1540, 1545, 1550, 1555, 1560, 1565, 1570, 1575, 1580, 1585, 1590, 1595, or about 1600 mg.

The therapeutically effective amount of Compound 1 can be administered once a day, twice a day, three times a day, four times a day, or more.

In various embodiments, the method of treating or ameliorating osteoarthritic pain or symptoms of osteoarthritis in a subject, is comprising administering to the subject a unit dose comprising about 400 mg, four times per day, of the Compound 1.

In various embodiments, the method of treating or ameliorating osteoarthritic pain or symptoms of osteoarthritis in a subject, is comprising administering to the subject a unit dose comprising about 800 mg, two times per day, of Compound 1.

In various embodiments, the therapeutically effective amount of Compound 1 is administered for about 1 day to about 90 days. The therapeutically effective amount of Compound 1 can be administered for about 1 day, 2 days, 3 days, 4 days, 5 days, 6 days, 7 days, 14 days, 28 days, or more. Administering of Compound 1 can continue for as long as the individual, in consultation with a physician, deems it necessary to maintain adequate pain control for their individual situation. In various embodiments, Compound 1 can be administered for about 1 month to about 24 months, or for the lifespan of the individual.

In various embodiments, administering Compound 1 under any of the conditions described herein can result in a maximum observed plasma concentration (Cmax) of about 5 pg/mL to about 300 pg/mL in a rat, mouse, dog, or human. The Cmax of Compound 1 can be about 10 pg/mL to about 280 pg/mL, about 20 pg/mL to about 260 pg/mL, about 40 pg/mL to about 240 pg/mL, about 50 pg/mL to about 220 pg/mL, about 60 pg/mL to about 200 pg/mL, about 70 pg/mL to about 180 pg/mL, about 80 pg/mL to about 160 pg/mL, about 90 pg/mL to about 140 pg/mL, or about 95 pg/mL to about 120 pg/mL. In various embodiments, the C ax of Compound 1 can be at least, equal to, or greater than about 5 pg/mL, 10 pg/mL, 20 pg/mL, 30 pg/mL, 40 pg/mL, 50 pg/mL, 60 pg/mL, 70 pg/mL, 80 pg/mL, 90 pg/mL, 100 pg/mL, 120 pg/mL, 140 pg/mL, 160 pg/mL, 180 pg/mL, 200 pg/mL, 220 pg/mL, 240 pg/mL, 260 pg/mL, 280 pg/mL, or about 300 pg/mL.

In various embodiments, administering Compound 1 under any of the conditions described herein results in an area under the curve (AUCINF) of about 100 hrpg/mL to about 3000 hr· pg/mL in a rat, mouse, dog, or human. The AUCINF of Compound 1 can be about 100 hrpg/mL to about 2800 hrpg/mL, about 200 hrpg/mL to about 2600 hrpg/mL, about 400 hrpg/mL to about 2400 hrpg/mL, about 500 hrpg/mL to about 2200 hrpg/mL, about 600 hrpg/mL to about 2000 hrpg/mL, about 700 hrpg/mL to about 1800 hrpg/mL, about 800 hrpg/mL to about 1600 hrpg/mL, about 900 hrpg/mL to about 1400 hrpg/mL, or about 950 hr-pg/mL to about 1200 hr-pg/mL. In various embodiments, the AUCINF of Compound 1 is at least, equal to, or greater than about 50 hrpg/mL. 100 hrpg/mL. 200 hr-pg/mL. 300 hr-pg/mL. 400 hr-pg/mL, 500 hrpg/mL, 600 hrpg/mL, 700 hr-pg/mL, 800 hrpg/mL, 900 hrpg/mL, 1000 hrpg/mL, 1200 hrpg/mL, 1400 hrpg/mL, 1600 hrpg/mL, 1800 hrpg/mL, 2000 hr-pg/mL, 2200 hr-pg/mL, 2400 hr-pg/mL, 2600 hr-pg/mL, 2800 hr-pg/mL, or about 3000 hr-pg/mL.

The methods described herein can include administering to the subject a therapeutically effective amount of at least one compound described herein, which is optionally formulated in a pharmaceutical composition. In various embodiments, a therapeutically effective amount of at least one compound described herein present in a pharmaceutical composition is the only therapeutically active compound in a pharmaceutical composition. In certain embodiments, the method further comprises administering to the subject an additional therapeutic agent that reduces or ameliorates pain.

In certain embodiments, administering the compound(s) described herein to the subject allows for administering a lower dose of the additional therapeutic agent as compared to the dose of the additional therapeutic agent alone that is required to achieve similar results in treating, preventing, or ameliorating pain in the subject. For example, in certain embodiments, the compound(s) described herein enhances the activity of the additional therapeutic compound, thereby allowing for a lower dose of the additional therapeutic compound to provide the same effect.

In certain embodiments, the compound(s) described herein and the therapeutic agent are co-administered to the subject. In other embodiments, the compound(s) described herein and the therapeutic agent are coformulated and co-administered to the subject.

In certain embodiments, the subject is a mammal. In other embodiments, the mammal is a human.

Combination Therapies

In various embodiments, the method includes administering a therapeutically effective amount of a composition containing Compound 1 in combination or adjunctively with at least one additional pharmaceutically active agent. The type of pharmaceutically active agent that can be administered in combination or adjunctively with Compound 1 is not particularly limited. Non-limiting examples of additional pharmaceutically active agents include acetaminophen, alpha-2 adrenergic agonists, aspirin, COX-1 inhibitors, COX-2 inhibitors, voltage-gated ion channel blockers (NaV, CaV and KaV families), ligand-gated ion channels (TRPV1, TRPV4, TRPA1, and TRPM8 antagonists and agonists), opioid analgesics (mu-, delta-, kappa-selective and mixed), non-opioid analgesics, non-steroidal anti-inflammatories, norepinephrine reuptake inhibitors, serotonin reuptake inhibitors, dual norepinephrine- serotonin reuptake inhibitors, anticonvulsants (lamotrigine) including the gabapentinoids (gabapentin, pregabalin, mirogabalin), antidepressants (including tricyclics such as amitriptyline, doxepin and desipramine), tramadol and tapentadol.

Non-limiting examples of analgesic drugs that can be useful in combination or adjunctive therapy with Compound 1 include without limitation acetaminophen, alfentanil, allylprodine, alphaprodine, anileridine, aspirin, benzylmorphine, bezitramide, buprenorphine, butorphanol, clonidine, clonitazene, codeine, cyclazocine, desomorphine, dextromoramide, dextropropoxyphene, dezocine, diampromide, diamorphone, dihydrocodeine, dihydromorphine, dimenoxadol, dimepheptanol, dimethylthiambutene, dioxaphetyl butyrate, dipipanone, duloxetine, eptazocine, ethoheptazine, ethylmethylthiambutene, ethylmorphine, etonitazene, fentanyl, gabapentin, heroin, hydrocodone, hydromorphone, hydroxypethidine, isomethadone, ketobemidone, levallorphan, levorphanol, levophenacyl-morphan, lofentanil, meperidine, meptazinol, metazocine, methadone, metopon, mirogabalin, morphine, myrophine, nalbuphine, nalorphine, narceine, ni comorphine, norlevorphanol, normethadone, normorphine, norpipanone, opium, oxycodone, oxymorphone, papaveretum, pentazocine, phenadoxone, phenazocine, phenomorphan, phenoperidine, piminodine, piritramide, pregabalin, proheptazine, promedol, properidine, propiram, propoxyphene, sufentanil, tapentadol, tilidine, tramadol, NO-naproxen, NCX-701, ALGRX-4975, pharmaceutically acceptable salts thereof, and any combinations thereof.

Non-limiting examples of anticonvulsants that can be useful in combination or adjunctively with Compound 1 include without limitation acetylpheneturide, albutoin, aminoglutethimide, 4-amino-3-hydroxybutyric acid, atrolactamide, beclamide, buramate, carbamazepine, cinromide, clomethiazole, clonazepam, decimemide, diethadione, dimethadione, doxenitoin, eterobarb, ethadione, ethosuximide, ethotoin, felbamate, fluoresone, fosphenyloin, gabapentin, ganaxolone, lamotrigine, levetiracetam, lorazepam, mephenyloin, mephobarbital, metharbital, methetoin, methsuximide, midazolam, mirogabalin, narcobarbital, nitrazepam, oxcarbazepine, paramethadione, phenacemide, phenetharbital, pheneturide, phenobarbital, phensuximide, phenylmethylbarbituric acid, phenyloin, phenethylate, pregabalin, primidone, progabide, remacemide, rufinamide, suclofenide, sulthiame, talampanel, tetrantoin, tiagabine, topiramate, trimethadione, valproic acid, valpromide, vigabatrin, zonisamide, pharmaceutically acceptable salts thereof, and any combinations thereof.

Non-limiting examples of antidepressants that can be useful in combination or adjunctively with Compound 1 include without limitation bicyclic, tricyclic and tetracyclic antidepressants, hydrazides, hydrazines, phenyloxazolidinones and pyrrolidones. Specific examples include adinazolam, adrafmil, amineptine, amitriptyline, amitriptylinoxide, amoxapine, befloxatone, bupropion, butacetin, butriptyline, caroxazone, citalopram, clomipramine, cotinine, demexiptiline, desipramine, dibenzepin, dimetacrine, dimethazan, dioxadrol, dothiepin, doxepin, duloxetine, etoperidone, femoxetine, fencamine, fenpentadiol, fluacizine, fluoxetine, fluvoxamine, hematoporphyrin, hypericin, imipramine, imipramine N- oxide, indalpine, indeloxazine, iprindole, iproclozide, iproniazid, isocarboxazid, levophacetoperane, lofepramine, maprotiline, medifoxamine, melitracen, metapramine, metralindole, mianserin, milnacipran, minaprine, mirtazapine, moclobemide, nefazodone, nefopam, nialamide, nomifensine, nortriptyline, noxiptilin, octamoxin, opipramol, oxaflozane, oxitriptan, oxypertine, paroxetine, phenelzine, piberaline, pizotyline, prolintane, propizepine, protriptyline, pyrisuccideanol, quinupramine, reboxetine, ritanserin, roxindole, rubidium chloride, sertraline, sulpiride, tandospirone, thiazesim, thozalinone, tianeptine, tofenacin, toloxatone, tranylcypromine, trazodone, trimipramine, tryptophan, venlafaxine, viloxazine, zimeldine, pharmaceutically acceptable salts thereof, and any combinations thereof.

The additional pharmaceutically active agent can be included with Compound 1 in the same dosage form or in a separate dosage form, and any of the dosage forms described herein can be suitably used for combining Compound 1 and an additional pharmaceutically active agent in the same dosage form. When the additional pharmaceutically active agent is present in a separate dosage form, the additional pharmaceutically active agent can be administered at the same time as Compound 1 or at a different time, such as about 1 hour to about 24 hours after administration of Compound 1. The additional pharmaceutically active agent can be administered for the entire duration of administration of Compound 1, or for a shorter or longer time.

Additional Administration/Dosing Regimens/Formulations

The regimen of administration may affect what constitutes an effective amount. The therapeutic formulations may be administered to the subject either prior to or after the onset of pain. Further, several divided dosages, as well as staggered dosages may be administered daily or sequentially, or the dose may be continuously infused, or may be a bolus injection. Further, the dosages of the therapeutic formulations may be proportionally increased or decreased as indicated by the exigencies of the therapeutic or prophylactic situation.

Administration of the compositions described herein to a patient, preferably a mammal, more preferably a human, may be carried out using known procedures, at dosages and for periods of time effective to treat pain in the patient. An effective amount of the therapeutic compound necessary to achieve a therapeutic effect may vary according to factors such as the state of the disease or disorder in the patient; the age, sex, and weight of the patient; and the ability of the therapeutic compound to treat, ameliorate, and/or prevent pain in the patient.

It is understood that the amount of compound dosed per day may be administered, in non-limiting examples, every day, every other day, every 2 days, every 3 days, every 4 days, or every 5 days. For example, with every other day administration, a 5 mg per day dose may be initiated on Monday with a first subsequent 5 mg per day dose administered on Wednesday, a second subsequent 5 mg per day dose administered on Friday, and so on.

In the case wherein the patient's status does improve, upon the doctor's discretion the administration of the compound(s) described herein is optionally given continuously; alternatively, the dose of drug being administered is temporarily reduced or temporarily suspended for a certain length of time (i.e., a "drug holiday"). The length of the drug holiday optionally varies between 2 days and 1 year, including by way of example only, 2 days, 3 days, 4 days, 5 days, 6 days, 7 days, 10 days, 12 days, 15 days, 20 days, 28 days, 35 days, 50 days, 70 days, 100 days, 120 days, 150 days, 180 days, 200 days, 250 days, 280 days, 300 days, 320 days, 350 days, or 365 days. The dose reduction during a drug holiday includes from 10%-100%, including, by way of example only, 10%, 15%, 20%, 25%, 30%, 35%,

40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, or 100%.

Once improvement of the patient's conditions has occurred, a maintenance dose is administered if necessary. Subsequently, the dosage or the frequency of administration, or both, is reduced to a level at which the improved disease is retained. In certain embodiments, patients require intermittent treatment on a long-term basis upon any recurrence of symptoms and/or infection.

The compounds described herein can be formulated in unit dosage form. The term "unit dosage form" refers to physically discrete units suitable as unitary dosage for patients undergoing treatment, with each unit containing a predetermined quantity of active material calculated to produce the desired therapeutic effect, optionally in association with a suitable pharmaceutical carrier. The unit dosage form may be for a single daily dose or one of multiple daily doses (e.g., about 1 to 4 or more times per day). When multiple daily doses are used, the unit dosage form may be the same or different for each dose.

Toxicity and therapeutic efficacy of such therapeutic regimens are optionally determined in cell cultures or experimental animals, including, but not limited to, the determination of the LD50 (the dose lethal to 50% of the population) and the ED50 (the dose therapeutically effective in 50% of the population). The dose ratio between the toxic and therapeutic effects is the therapeutic index, which is expressed as the ratio between LD50 and ED50. The data obtained from cell culture assays and animal studies are optionally used in formulating a range of dosage for use in human. The dosage of such compounds lies preferably within a range of circulating concentrations that include the ED50 with minimal toxicity. The dosage optionally varies within this range depending upon the dosage form employed and the route of administration utilized.

Those skilled in the art will recognize, or be able to ascertain using no more than routine experimentation, numerous equivalents to the specific procedures, embodiments, claims, and examples described herein. Such equivalents were considered to be within the scope of this application and covered by the claims appended hereto. For example, it should be understood, that modifications in reaction conditions, including but not limited to reaction times, reaction size/volume, and experimental reagents, such as solvents, catalysts, pressures, atmospheric conditions, e.g., nitrogen atmosphere, and reducing/oxidizing agents, with art- recognized alternatives and using no more than routine experimentation, are within the scope of the present application.

Actual dosage levels of the active ingredients in the pharmaceutical compositions described herein may be varied so as to obtain an amount of the active ingredient that is effective to achieve the desired therapeutic response for a particular patient, composition, and mode of administration, without being toxic to the patient.

In particular, the selected dosage level depends upon a variety of factors including the activity of the particular compound employed, the time of administration, the rate of excretion of the compound, the duration of the treatment, other drugs, compounds or materials used in combination with the compound, the age, sex, weight, condition, general health and prior medical history of the patient being treated, and like factors well, known in the medical arts.

A medical doctor, e.g., physician or veterinarian, having ordinary skill in the art may readily determine and prescribe the effective amount of the pharmaceutical composition required. For example, the physician or veterinarian could start doses of the compounds described herein employed in the pharmaceutical composition at levels lower than that required in order to achieve the desired therapeutic effect and gradually increase the dosage until the desired effect is achieved.

In particular embodiments, it is especially advantageous to formulate the compound in dosage unit form for ease of administration and uniformity of dosage. Dosage unit form as used herein refers to physically discrete units suited as unitary dosages for the patients to be treated; each unit containing a predetermined quantity of therapeutic compound calculated to produce the desired therapeutic effect in association with the required pharmaceutical vehicle. The dosage unit forms of the compound(s) described herein are dictated by and directly dependent on (a) the unique characteristics of the therapeutic compound and the particular therapeutic effect to be achieved, and (b) the limitations inherent in the art of compounding/formulating such a therapeutic compound for the treatment of pain in a patient.

In certain embodiments, the compositions described herein are formulated using one or more pharmaceutically acceptable excipients or carriers. In certain embodiments, the pharmaceutical compositions described herein comprise a therapeutically effective amount of a compound described herein and a pharmaceutically acceptable carrier.

The carrier may be a solvent or dispersion medium containing, for example, water, ethanol, polyol (for example, glycerol, propylene glycol, and liquid polyethylene glycol, and the like), suitable mixtures thereof, and vegetable oils. The proper fluidity may be maintained, for example, by the use of a coating such as lecithin, by the maintenance of the required particle size in the case of dispersion and by the use of surfactants. Prevention of the action of microorganisms may be achieved by various antibacterial and antifungal agents, for example, parabens, chlorobutanol, phenol, ascorbic acid, thimerosal, and the like. In many cases, it is preferable to include isotonic agents, for example, sugars, sodium chloride, or poly alcohols such as mannitol and sorbitol, in the composition. Prolonged absorption of the injectable compositions may be brought about by including in the composition an agent which delays absorption, for example, aluminum monostearate or gelatin.

In certain embodiments, the compositions described herein are administered to the patient in dosages that range from one to five times per day or more. In other embodiments, the compositions described herein are administered to the patient in range of dosages that include, but are not limited to, once every day, every two, days, every three days to once a week, and once every two weeks. It is readily apparent to one skilled in the art that the frequency of administration of the various combination compositions described herein varies from individual to individual depending on many factors including, but not limited to, age, disease or disorder to be treated, gender, overall health, and other factors. Thus, administration of the compounds and compositions described herein should not be construed to be limited to any particular dosage regime and the precise dosage and composition to be administered to any patient is determined by the attending physician taking all other factors about the patient into account.

In certain embodiments, a composition as described herein is a packaged pharmaceutical composition comprising a container holding a therapeutically effective amount of a compound described herein, alone or in combination with a second pharmaceutical agent; and instructions for using the compound to treat, prevent, and/or reduce one or more symptoms of pain in a patient.

Formulations may be employed in admixtures with conventional excipients, i.e., pharmaceutically acceptable organic or inorganic carrier substances suitable for oral, parenteral, nasal, intravenous, subcutaneous, enteral, or any other suitable mode of administration, known to the art. The pharmaceutical preparations may be sterilized and if desired mixed with auxiliary agents, e.g., lubricants, preservatives, stabilizers, wetting agents, emulsifiers, salts for influencing osmotic pressure buffers, coloring, flavoring and/or aromatic substances and the like. They may also be combined where desired with other active agents, e.g., other analgesic agents.

Routes of administration of any of the compositions described herein include oral, nasal, rectal, intravaginal, parenteral, buccal, sublingual or topical. The compounds for use in the compositions described herein can be formulated for administration by any suitable route, such as for oral or parenteral, for example, transdermal, transmucosal (e.g., sublingual, lingual, (trans)buccal, (trans)urethral, vaginal (e.g., trans- and perivaginally), (intra)nasal and (trans)rectal), intravesical, intrapulmonary, intraduodenal, intragastrical, intrathecal, subcutaneous, intramuscular, intradermal, intra-arterial, intravenous, intrabronchial, inhalation, and topical administration.

Suitable compositions and dosage forms include, for example, tablets, capsules, caplets, pills, gel caps, troches, dispersions, suspensions, solutions, syrups, granules, beads, transdermal patches, gels, powders, pellets, magmas, lozenges, creams, pastes, plasters, lotions, discs, suppositories, liquid sprays for nasal or oral administration, dry powder or aerosolized formulations for inhalation, compositions and formulations for intravesical administration and the like. It should be understood that the formulations and compositions described herein are not limited to the particular formulations and compositions that are described herein. Oral Administration

For oral application, particularly suitable are tablets, dragees, liquids, drops, suppositories, or capsules, caplets and gelcaps. The compositions intended for oral use may be prepared according to any method known in the art and such compositions may contain one or more agents selected from the group consisting of inert, non-toxic pharmaceutically excipients that are suitable for the manufacture of tablets. Such excipients include, for example an inert diluent such as lactose; granulating and disintegrating agents such as cornstarch; binding agents such as starch; and lubricating agents such as magnesium stearate. The tablets may be uncoated or they may be coated by known techniques for elegance or to delay the release of the active ingredients. Formulations for oral use may also be presented as hard gelatin capsules wherein the active ingredient is mixed with an inert diluent.

For oral administration, the compound(s) described herein can be in the form of tablets or capsules prepared by conventional means with pharmaceutically acceptable excipients such as binding agents (e.g., polyvinylpyrrolidone, hydroxypropylcellulose or hydroxypropyl methylcellulose); fillers (e.g., cornstarch, lactose, microcrystalline cellulose or calcium phosphate); lubricants (e.g., magnesium stearate, talc, or silica); disintegrates (e.g., sodium starch gly collate); or wetting agents (e.g., sodium lauryl sulphate). If desired, the tablets may be coated using suitable methods and coating materials such as OPADRY™ film coating systems available from Colorcon, West Point, Pa. (e.g., OPADRY™ OY Type, OYC Type, Organic Enteric OY-P Type, Aqueous Enteric OY-A Type, OY-PM Type and OPADRY™ White, 32K18400). Liquid preparation for oral administration may be in the form of solutions, syrups or suspensions. The liquid preparations may be prepared by conventional means with pharmaceutically acceptable additives such as suspending agents (e.g., sorbitol syrup, methyl cellulose or hydrogenated edible fats); emulsifying agent (e.g., lecithin or acacia); non-aqueous vehicles (e.g., almond oil, oily esters or ethyl alcohol); and preservatives (e.g., methyl or propyl p-hydroxy benzoates or sorbic acid).

Compositions as described herein can be prepared, packaged, or sold in a formulation suitable for oral or buccal administration. A tablet that includes Compound 1 can, for example, be made by compressing or molding the active ingredient, optionally with one or more additional ingredients. Compressed tablets may be prepared by compressing, in a suitable device, the active ingredient in a free-flowing form such as a powder or granular preparation, optionally mixed with one or more of a binder, a lubricant, an excipient, a surface active agent, and a dispersing agent. Molded tablets may be made by molding, in a suitable device, a mixture of the active ingredient, a pharmaceutically acceptable carrier, and at least sufficient liquid to moisten the mixture. Pharmaceutically acceptable excipients used in the manufacture of tablets include, but are not limited to, inert diluents, granulating and disintegrating agents, dispersing agents, surface-active agents, disintegrating agents, binding agents, and lubricating agents.

Suitable dispersing agents include, but are not limited to, potato starch, sodium starch gly collate, poloxamer 407, or poloxamer 188. One or more dispersing agents can each be individually present in the composition in an amount of about 0.01% w/w to about 90% w/w relative to weight of the dosage form. One or more dispersing agents can each be individually present in the composition in an amount of at least, greater than, or less than about 0.01%, 0.05%, 0.1%, 0.5%, 1%, 2%, 3%, 4%, 5%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, or 90% w/w relative to weight of the dosage form.

Surface-active agents (surfactants) include cationic, anionic, or non-ionic surfactants, or combinations thereof. Suitable surfactants include, but are not limited to, behentrimonium chloride, benzalkonium chloride, benzethonium chloride, benzododecinium bromide, carbethopendecinium bromide, cetalkonium chloride, cetrimonium bromide, cetrimonium chloride, cetylpyridine chloride, didecyldimethylammonium chloride, dimethyldioctadecylammonium bromide, dimethyldioctadecylammonium chloride, domiphen bromide, lauryl methyl gluceth-10 hydroxypropyl dimonium chloride, tetramethylammonium hydroxide, thonzonium bromide, stearalkonium chloride, octenidine dihydrochloride, olaflur, N-oleyl-l,3-propanediamine, 2-acrylamido-2-methylpropane sulfonic acid, alkylbenzene sulfonates, ammonium lauryl sulfate, ammonium perfluorononanoate, docusate, disodium cocoamphodiacetate, magnesium laureth sulfate, perfluorobutanesulfonic acid, perfluorononanoic acid, perfluorooctanesulfonic acid, perfluorooctanoic acid, potassium lauryl sulfate, sodium alkyl sulfate, sodium dodecyl sulfate, sodium laurate, sodium laureth sulfate, sodium lauroyl sarcosinate, sodium myreth sulfate, sodium nonanoyloxybenzenesulfonate, sodium pareth sulfate, sodium stearate, sodium sulfosuccinate esters, cetomacrogol 1000, cetostearyl alcohol, cetyl alcohol, cocamide diethanolamine, cocamide monoethanolamine, decyl glucoside, decyl polyglucose, glycerol monostearate, octylphenoxypolyethoxyethanol CA-630, isoceteth-20, lauryl glucoside, octylphenoxypolyethoxyethanol P-40, Nonoxynol-9, Nonoxynols, nonyl phenoxypolyethoxylethanol (NP-40), octaethylene glycol monododecyl ether, N-octyl beta- D-thioglucopyranoside, octyl glucoside, oleyl alcohol, PEG- 10 sunflower glycerides, pentaethylene glycol monododecyl ether, polidocanol, poloxamer, poloxamer 407, polyethoxylated tallow amine, polyglycerol polyricinoleate, polysorbate, polysorbate 20, polysorbate 80, sorbitan, sorbitan monolaurate, sorbitan monostearate, sorbitan tristearate, stearyl alcohol, surfactin, Triton X-100, and Tween 80. One or more surfactants can each be individually present in the composition in an amount of about 0.01% w/w to about 90% w/w relative to weight of the dosage form. One or more surfactants can each be individually present in the composition in an amount of at least, greater than, or less than about 0.01%, 0.05%, 0.1%, 0.5%, 1%, 2%, 3%, 4%, 5%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, or 90% w/w relative to weight of the dosage form.

Suitable diluents include, but are not limited to, calcium carbonate, magnesium carbonate, magnesium oxide, sodium carbonate, lactose, microcrystalline cellulose, calcium phosphate, calcium hydrogen phosphate, and sodium phosphate, Cellactose ® 80 (75 % a- lactose monohydrate and 25 % cellulose powder), mannitol, pre-gelatinized starch, starch, sucrose, sodium chloride, talc, anhydrous lactose, and granulated lactose. One or more diluents can each be individually present in the composition in an amount of about 0.01% w/w to about 90% w/w relative to weight of the dosage form. One or more diluents can each be individually present in the composition in an amount of at least, greater than, or less than about 0.01%, 0.05%, 0.1%, 0.5%, 1%, 2%, 3%, 4%, 5%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, or 90% w/w relative to weight of the dosage form.

Suitable granulating and disintegrating agents include, but are not limited to, sucrose, copovidone, com starch, microcrystalline cellulose, methyl cellulose, sodium starch gly collate, pregelatinized starch, povidone, sodium carboxy methyl cellulose, sodium alginate, citric acid, croscarmellose sodium, cellulose, carboxymethylcellulose calcium, colloidal silicone dioxide, crosspovidone and alginic acid. One or more granulating or disintegrating agents can each be individually present in the composition in an amount of about 0.01% w/w to about 90% w/w relative to weight of the dosage form. One or more granulating or disintegrating agents can each be individually present in the composition in an amount of at least, greater than, or less than about 0.01%, 0.05%, 0.1%, 0.5%, 1%, 2%, 3%, 4%, 5%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, or 90% w/w relative to weight of the dosage form.

Suitable binding agents include, but are not limited to, gelatin, acacia, pre-gelatinized maize starch, polyvinylpyrrolidone, anhydrous lactose, lactose monohydrate, hydroxypropyl methylcellulose, methylcellulose, povidone, polyacrylamides, sucrose, dextrose, maltose, gelatin, polyethylene glycol. One or more binding agents can each be individually present in the composition in an amount of about 0.01% w/w to about 90% w/w relative to weight of the dosage form. One or more binding agents can each be individually present in the composition in an amount of at least, greater than, or less than about 0.01%, 0.05%, 0.1%, 0.5%, 1%, 2%, 3%, 4%, 5%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, or 90% w/w relative to weight of the dosage form.

Suitable lubricating agents include, but are not limited to, magnesium stearate, calcium stearate, hydrogenated castor oil, glyceryl monostearate, glyceryl behenate, mineral oil, polyethylene glycol, poloxamer 407, poloxamer 188, sodium laureth sulfate, sodium benzoate, stearic acid, sodium stearyl fumarate, silica, and talc. One or more lubricating agents can each be individually present in the composition in an amount of about 0.01% w/w to about 90% w/w relative to weight of the dosage form. One or more lubricating agents can each be individually present in the composition in an amount of at least, greater than, or less than about 0.01%, 0.05%, 0.1%, 0.5%, 1%, 2%, 3%, 4%, 5%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, or 90% w/w relative to weight of the dosage form.

Tablets can be uncoated or they may be coated using known methods to achieve delayed disintegration in the gastrointestinal tract of a subject, thereby providing sustained release and absorption of the active ingredient. By way of example, a material such as glyceryl monostearate or glyceryl distearate may be used to coat tablets. Further by way of example, tablets may be coated using methods described in U.S. Patent Nos. 4,256,108; 4,160,452; and 4,265,874 to form osmotically controlled release tablets. Tablets may further comprise a sweetening agent, a flavoring agent, a coloring agent, a preservative, or some combination of these in order to provide for pharmaceutically elegant and palatable preparation.

Tablets can also be enterically coated such that the coating begins to dissolve at a certain pH, such as at about pH 5.0 to about pH 7.5, thereby releasing Compound 1. The coating can contain, for example, EUDRAGIT ® L, S, FS, and/or E polymers with acidic or alkaline groups to allow release of Compound 1 in a particular location, including in any desired section(s) of the intestine. The coating can also contain, for example, EUDRAGIT ^® RL and/or RS polymers with cationic or neutral groups to allow for time-controlled release of Compound 1 by pH-independent swelling.

Hard capsules that include Compound 1 can be made using a physiologically degradable composition, such as gelatin. Such hard capsules include Compound 1, and can further include additional ingredients including, for example, an inert solid diluent such as calcium carbonate, calcium phosphate, or kaolin.

Soft gelatin capsules that include Compound 1 can be made using a physiologically degradable composition, such as gelatin. Such soft capsules include Compound 1, which may be mixed with water or an oil medium such as peanut oil, liquid paraffin, or olive oil.

Liquid formulations of compositions described herein which are suitable for oral administration can be prepared, packaged, and sold either in liquid form or in the form of a dry product intended for reconstitution with water or another suitable vehicle prior to use.

Parenteral Administration

As used herein, "parenteral administration" of a pharmaceutical composition includes any route of administration characterized by physical breaching of a tissue of a subject and administration of the pharmaceutical composition through the breach in the tissue. Parenteral administration thus includes, but is not limited to, administration of a pharmaceutical composition by injection of the composition. In particular, parenteral administration is contemplated to include, but is not limited to, intravenous, subcutaneous, intraperitoneal, intramuscular, intrastemal injection, and kidney dialytic infusion techniques.

For parenteral administration, the compound(s) described herein may be formulated for injection or infusion, for example, intravenous, intramuscular or subcutaneous injection or infusion, or for administration in a bolus dose and/or continuous infusion. Suspensions, solutions or emulsions in an oily or aqueous vehicle, optionally containing other formulatory agents such as suspending, stabilizing and/or dispersing agents may be used.

Sterile injectable forms of the compositions described herein may be aqueous or oleaginous suspension. These suspensions may be formulated according to techniques known in the art using suitable dispersing or wetting agents and suspending agents. The sterile injectable preparation may also be a sterile injectable solution or suspension in anon- toxic parenterally-acceptable diluent or solvent, for example as a solution in 1, 3-butanediol. Among the acceptable vehicles and solvents that may be employed are water, Ringer's solution and isotonic sodium chloride solution. Sterile, fixed oils are conventionally employed as a solvent or suspending medium. For this purpose, any bland fixed oil may be employed including synthetic mono- or di-glycerides. Fatty acids, such as oleic acid and its glyceride derivatives are useful in the preparation of injectables, as are natural pharmaceutically acceptable oils, such as olive oil or castor oil, especially in their polyoxyethylated versions. These oil solutions or suspensions may also contain a long-chain alcohol diluent or dispersant, such as Ph. Helv or similar alcohol.

Formulations of a pharmaceutical composition suitable for parenteral administration include the active ingredient ( e.g . Compound 1) combined with a pharmaceutically acceptable carrier, such as sterile water or sterile isotonic saline. Such formulations may be prepared, packaged, or sold in a form suitable for bolus administration or for continuous administration. Injectable formulations may be prepared, packaged, or sold in unit dosage form, such as in ampules or in multi-dose containers containing a preservative. Formulations for parenteral administration include, but are not limited to, suspensions, solutions, emulsions in oily or aqueous vehicles, pastes, and implantable sustained-release or biodegradable formulations. Such formulations may further comprise one or more additional ingredients including, but not limited to, suspending, stabilizing, or dispersing agents. In one embodiment of a formulation for parenteral administration, the active ingredient is provided in dry (i.e., powder or granular) form for reconstitution with a suitable vehicle (e.g., sterile pyrogen-free water) prior to parenteral administration of the reconstituted composition.

The pharmaceutical compositions may be prepared, packaged, or sold in the form of a sterile injectable aqueous or oily suspension or solution. This suspension or solution may be formulated according to the known art, and may comprise, in addition to the active ingredient, additional ingredients such as antioxidants, dispersing agents, wetting agents, or suspending agents described herein. Such sterile injectable formulations can be prepared using a non-toxic parenterally-acceptable diluent or solvent, such as water or 1,3-butane diol, for example. Other acceptable diluents and solvents include, but are not limited to, Ringer's solution, isotonic sodium chloride solution, and fixed oils such as synthetic mono- or di glycerides. Other parentally-administrable formulations which are useful include those which comprise the active ingredient in microcrystalline form, in a liposomal preparation, or as a component of a biodegradable polymer system. Compositions for sustained release or implantation may comprise pharmaceutically acceptable polymeric or hydrophobic materials such as an emulsion, an ion exchange resin, a sparingly soluble polymer, or a sparingly soluble salt.

In various embodiments, Compound 1 is administered to a patient by intravenous infusion over time. The dose of Compound 1 administered to the patient can be readily determined by a physician based on art-recognized patient characteristics as described herein. In various embodiments, the concentration of Compound 1 in the infusion is from about 0.01 mg/mL to about 3000 mg/mL. The volume of the infusion administered to the patient can be from about 1 mL to about 2000 mL in a given 24-h period. The intravenous infusion can be over any period as determined by the particular needs of the patient and their medical condition, which can readily be determined by a physician. In various embodiments, Compound 1 is administered over about 1 min to about 60 min, or over about 1 h to about 24 h. Suitable devices for use with intravenous infusion of Compound 1 include the BD Alaris™ Pump Module, the Alaris™ Syringe Module, and the like. Compound 1 can also be administered using a PCA (patient-controlled analgesia) device, wherein the patient controls when a bolus of the infusion containing Compound 1 is delivered. The volume of the bolus and the concentration of Compound 1 in the bolus can be any of the amounts described herein with respect to intravenous infusion. Suitable PCA devices for PCA delivery of Compound 1 include the Alaris™ PCA Module, and the like. Additional fluids, including other medications, saline solution, electrolytes, nutrition fluids (e.g., total parenteral nutrition), blood, and blood products, can be administered to the patient consecutively or concurrently with the intravenous infusion of Compound 1.

Topical Administration

An obstacle for topical administration of pharmaceuticals is the stratum comeum layer of the epidermis. The stratum comeum is a highly resistant layer comprised of protein, cholesterol, sphingolipids, free fatty acids and various other lipids, and includes comified and living cells. One of the factors that limit the penetration rate (flux) of a compound through the stratum comeum is the amount of the active substance that can be loaded or applied onto the skin surface. The greater the amount of active substance which is applied per unit of area of the skin, the greater the concentration gradient between the skin surface and the lower layers of the skin, and in turn the greater the diffusion force of the active substance through the skin. Therefore, a formulation containing a greater concentration of the active substance is more likely to result in penetration of the active substance through the skin, and more of it, and at a more consistent rate, than a formulation having a lesser concentration, all other things being equal.

Enhancers of permeation can be used. These materials increase the rate of penetration of drugs across the skin. Typical enhancers in the art include ethanol, glycerol monolaurate, PGML (polyethylene glycol monolaurate), dimethylsulfoxide, and the like. Other enhancers include oleic acid, oleyl alcohol, ethoxy diglycol, laurocapram, alkanecarboxylic acids, polar lipids, or N-methyl-2-pyrrolidone.

One acceptable vehicle for topical delivery of some of the compositions described herein may contain liposomes. The composition of the liposomes and their use are known in the art (for example, see U.S. Patent No. 6,323,219). A topical dosage form of the inventive compound(s) can be optionally combined with other ingredients such as adjuvants, anti-oxidants, chelating agents, surfactants, foaming agents, wetting agents, emulsifying agents, viscosifiers, buffering agents, preservatives, and the like. In various embodiments, a permeation or penetration enhancer is included in the composition and is effective in improving the percutaneous penetration of the active ingredient into and through the stratum comeum with respect to a composition lacking the permeation enhancer. Various permeation enhancers, including oleic acid, oleyl alcohol, ethoxy diglycol, laurocapram, alkanecarboxylic acids, dimethylsulfoxide, polar lipids, or N- methyl-2-pyrrolidone, are known to those of skill in the art. In another aspect, the composition may further comprise a hydrotropic agent, which functions to increase disorder in the structure of the stratum comeum, and thus allows increased transport across the stratum comeum. Various hydrotropic agents such as isopropyl alcohol, propylene glycol, or sodium xylene sulfonate, are known to those of skill in the art.

A topical dosage form of the inventive compound(s) should be applied in an amount effective to affect desired changes. As used herein "amount effective" shall mean an amount sufficient to cover the region of skin surface where a change is desired. In various embodiments, Compound 1 can be present in the amount of from about 0.0001% to about 15% by weight volume of the composition. In various embodiments, Compound 1 can be present in an amount from about 0.0005% to about 5% of the composition; most preferably, it should be present in an amount of from about 0.001% to about 1% of the composition.

Rectal Administration

Compositions described herein can be prepared, packaged, or sold in a formulation suitable for rectal administration. Such a composition may be in the form of, for example, a suppository, a retention enema preparation, and a solution for rectal or colonic irrigation.

Suppository formulations may be made by combining the active ingredient with a non-irritating pharmaceutically acceptable excipient which is solid at ordinary room temperature (i.e., about 20°C) and which is liquid at the rectal temperature of the subject (i.e., about 37°C in a healthy human). Suitable pharmaceutically acceptable excipients include, but are not limited to, cocoa butter, polyethylene glycols, and various glycerides.

Suppository formulations may further comprise various additional ingredients including, but not limited to, antioxidants, and preservatives.

Retention enema preparations or solutions for rectal or colonic irrigation may be made by combining Compound 1 with a pharmaceutically acceptable liquid carrier. As is well known in the art, enema preparations may be administered using, and may be packaged within, a delivery device adapted to the rectal anatomy of the subject. Enema preparations may further comprise various additional ingredients including, but not limited to, antioxidants, and preservatives.

Additional Administration Forms

Additional dosage forms suitable for use with the compound(s) and compositions described herein include dosage forms as described in U.S. Patents Nos. 6,340,475; 6,488,962; 6,451,808; 5,972,389; 5,582,837; and 5,007,790. Additional dosage forms suitable for use with the compound(s) and compositions described herein also include dosage forms as described in U.S. Patent Applications Nos. 20030147952; 20030104062; 20030104053; 20030044466; 20030039688; and 20020051820. Additional dosage forms suitable for use with the compound(s) and compositions described herein also include dosage forms as described in PCT Applications Nos. WO 03/35041; WO 03/35040; WO 03/35029; WO 03/35177; WO 03/35039; WO 02/96404; WO 02/32416; WO 01/97783; WO 01/56544; WO 01/32217; WO 98/55107; WO 98/11879; WO 97/47285; WO 93/18755; and WO 90/11757.

Controlled Release Formulations and Drug Delivery Systems

In certain embodiments, the formulations described herein can be, but are not limited to, short-term, rapid-offset, as well as controlled, for example, sustained release, delayed release and pulsatile release formulations.

The term sustained release is used in its conventional sense to refer to a drug formulation that provides for gradual release of a drug over an extended period of time, and that may, although not necessarily, result in substantially constant blood levels of a drug over an extended time period. The period of time may be as long as a month or more and should be a release which is longer that the same amount of agent administered in bolus form.

For sustained release, the compounds may be formulated with a suitable polymer or hydrophobic material which provides sustained release properties to the compounds. As such, the compounds for use with the method(s) described herein may be administered in the form of microparticles, for example, by injection or in the form of wafers or discs by implantation.

In some cases, the dosage forms to be used can be provided as slow or controlled- release of one or more active ingredients therein using, for example, hydropropylmethyl cellulose, other polymer matrices, gels, permeable membranes, osmotic systems, multilayer coatings, microparticles, liposomes, or microspheres or a combination thereof to provide the desired release profile in varying proportions. Suitable controlled-release formulations known to those of ordinary skill in the art, including those described herein, can be readily selected for use with the pharmaceutical compositions described herein. Thus, single unit dosage forms suitable for oral administration, such as tablets, capsules, gelcaps, and caplets, that are adapted for controlled-release are encompassed by the compositions and dosage forms described herein.

Most controlled-release pharmaceutical products have a common goal of improving drug therapy over that achieved by their non-controlled counterparts. Ideally, the use of an optimally designed controlled-release preparation in medical treatment is characterized by a minimum of drug substance being employed to cure or control the condition in a minimum amount of time. Advantages of controlled-release formulations include extended activity of the drug, reduced dosage frequency, and increased patient compliance. In addition, controlled-release formulations can be used to affect the time of onset of action or other characteristics, such as blood level of the drug, and thus can affect the occurrence of side effects.

Most controlled-release formulations are designed to initially release an amount of drug that promptly produces the desired therapeutic effect, and gradually and continually release of other amounts of drug to maintain this level of therapeutic effect over an extended period of time. In order to maintain this constant level of drug in the body, the drug must be released from the dosage form at a rate that will replace the amount of drug being metabolized and excreted from the body.

Controlled-release of an active ingredient can be stimulated by various inducers, for example pH, temperature, enzymes, water, or other physiological conditions or compounds. The term "controlled-release component" is defined herein as a compound or compounds, including, but not limited to, polymers, polymer matrices, gels, permeable membranes, liposomes, or microspheres or a combination thereof that facilitates the controlled-release of the active ingredient. In one embodiment, the compound(s) described herein are administered to a patient, alone or in combination with another pharmaceutical agent, using a sustained release formulation.

The term delayed release is used herein in its conventional sense to refer to a drug formulation that provides for an initial release of the drug after some delay following drug administration and that mat, although not necessarily, includes a delay of from about 10 minutes up to about 12 hours. The term pulsatile release is used herein in its conventional sense to refer to a drug formulation that provides release of the drug in such a way as to produce pulsed plasma profiles of the drug after drug administration.

The term immediate release is used in its conventional sense to refer to a drug formulation that provides for release of the drug immediately after drug administration.

As used herein, short-term refers to any period of time up to and including about 8 hours, about 7 hours, about 6 hours, about 5 hours, about 4 hours, about 3 hours, about 2 hours, about 1 hour, about 40 minutes, about 20 minutes, or about 10 minutes and any or all whole or partial increments thereof after drug administration after drug administration.

As used herein, rapid-offset refers to any period of time up to and including about 8 hours, about 7 hours, about 6 hours, about 5 hours, about 4 hours, about 3 hours, about 2 hours, about 1 hour, about 40 minutes, about 20 minutes, or about 10 minutes, and any and all whole or partial increments thereof after drug administration.

Examples

Various embodiments of the present application can be better understood by reference to the following Examples which are offered by way of illustration. The scope of the present application is not limited to the Examples given herein.

Example 1: Preparation of Compound 1 Zwitterion

L-Peniciilamine 2-chlorobenzoxazoie Compound 1 Zwitterion

Purified water (8 volumes) was degassed with argon for approximately 30 minutes /.-penicillamine (1.6756 mol) was added and stirred for approximately 10 minutes maintaining the temperature below 30°C. The mixture was cooled to 10 ± 5°C. A cooled solution of sodium hydroxide (3.3512 mol) in degassed water (2 volumes) was added slowly to the above mass while maintaining temperature below 20°C, followed by slow addition of 2-chlorobenzoxazole (1.8431 mol) below 30°C. After complete addition the reaction mass was allowed to reach ambient temperature and was stirred for not less than 8 h at ambient temperature. Upon completion of the reaction, the reaction mixture was cooled to 10 ± 5°C, diluted with /.vopropyl alcohol (10 volumes) and acidified to pH 4.3 - 4.6 by dropwise addition of 2N aqueous hydrochloric acid below 30°C. The solution was stirred for approximately 16 h at below 5 ± 5°C. The solid was isolated by filtration, washed with iso propyl alcohol (3 volumes), and dried to get the zwitterion as white solid (302 g, 67.7%).

Example 2: Preparation of Compound 1 from Compound 1 Zwitterion

Compound 1 Zwitterion Compound 1

The zwitterion was added to /so-propyl alcohol (17.5 volumes) and cooled to 5 ± 5°C. Freshly prepared 2M HCI in /.vopropyl alcohol (1.05 equivalents with regard to zwitterion) was added below 10°C. The mixture was stirred for approximately 15 min, and the clear solution filtered under inert atmosphere. The filtrate was stirred not less than 16 h at 5 ± 5°C. The mixture was concentrated to approximately 3 volumes below 30°C, methyl tert- butyl ether (MTBE) was added (5 volumes) and kept at 5 ± 5°C for not less than 20 h. The solid formed was isolated by filtration and washed with MTBE (3 volumes). The isolated solid was dried in vacuum tray drier at 50 ± 5°C for approximately 12 h to obtain Compound 1 as crystalline white solid.

Example 3: Preparation of des- HCI Compound 1 des- HCI Compound 1 (i.e. lacking the HCI addition salt of Compound 1) can be prepared according to Scheme 1:

Scheme 1

(i) Preparation ofN-(2-Methoxyphenyl)cyanamide (2)

2

Aqueous ammonia (25%, 90 mL) was added to a stirred and ice-cooled suspension of l-(2-methoxyphenyl)thiourea (1) (5.00 g, 27.44 mmol) in acetonitrile (90 mL). Diacetoxyiodobenzene (10.60 g, 32.92 mmol) was added portion-wise over a period of 10 min. The reaction mixture was stirred at room temperature for 4 h, and the precipitated sulfur was filtered. The filtrate was concentrated to approximately 50% of its initial volume and extracted with ethyl acetate (3 x 20 mL). The ethyl acetate layer was washed with water (2 x 30 mL) and then with brine (50 mL). The organic layer was dried over anhydrous solid Na2SC>4, filtered and the filtrate concentrated under reduced pressure. The resultant residue was purified by flash column chromatography using petroleum ether/ethyl ether (1:1) to give the N-(2-methoxyphenyl)-cyanamide (2) (3.33 g, 82 % yield). 300 MHz 'H-NMR (CDCb, ppm): 7.08 (ddd, J=7.5, 1.9, 0.5 Hz, 1H) 7.04 (ddd, J=7.5, 7.5, 1.9 Hz) 6.98 (ddd, J=7.5, 7.5, 1.7 Hz) 6.88 (dd, J=7.5, 1.7 Hz) 6.26 (s, 1H) 3.88 (s, 3H). ESI-MS (m/z): 149 [M+H] ⁺ .

(ii) Preparation of ((R)-2-((2-methoxyphenyl)amino)-5,5-dimethyl-4,5- dihydrothiazole-4-carboxylic acid (3)

A mixture /V-(2-methoxyphenyl)cyanamide (2) (1.00 g, 6.75 mmol) and /.- penicillamine (1.21 g, 8.10 mmol) in deionized water / acetonitrile (20 mL/20 mL) was heated at reflux under an argon atmosphere for 2 h. The mixture was then concentrated under reduced pressure, and residue purified by reverse phase chromatography to afford (i?)-2-((2- methoxyphenyl)amino)-5,5-dimethyl-4,5-dihydrothiazole-4-carb oxylic acid (3) (0.92 g, 49% yield). 300 MHz ¾-NMR (CDiOD, ppm): 7.43-7.33 (m, 2H) 7.15 (dd, J=8.3, 1.1 Hz, 1H) 7.03 (ddd, J=7.7, 7.7, 1.2 Hz) 4.42 (s, 1H) 3.91 (s, 3H) 1.77 (s, 3H) 1.60 (s, 3H). ESI-MS (m/z): 281 [M+H] ⁺ .

(iii) Preparation of (R)-2-((2-hydroxyphenyl)amino)-5,5-dimethyl-4,5- dihydrothiazole-4-carboxylic acid (4)

Neat BBr ₃ (2.19 mL, 12.84 mmol) was added to a solution of ((R)-2-((2- methoxyphenyl)amino)-5,5-dimethyl-4,5-dihydrothiazole-4-carb oxylic acid (3) (360 mg,

1.28 mmol) in CH2CI2 (20 mL) at 0 °C. The reaction mixture was stirred at ambient temperature for 3 h, then water (2 mL) was added and the resulting suspension was stirred for 10 min. The resultant precipitate was filtered and removed. The filtrate was evaporated and purified by reverse phase chromatography to afford (//)-2-((2-hydro\y phenyl )amino)-5.5- dimethyl-4,5-dihydrothiazole-4-carboxylic acid (4) (210 mg, 64% yield). 300 MHz 'H-NMR (CD3OD, ppm): 6.94-6.86 (m, 2H) 6.82-6.77 (m, 1H) 6.73 (ddd, J=7.5, 7.5, 1.5 Hz) 4.19 (s, 1H) 3.91 1.68 (s, 3H) 1.49 (s, 3H). ESI-MS (m/z): 267 [M+H] ⁺ .

Example 4: Amorphous Compound 1

An amorphous form of Compound 1 can also be prepared as follows: ( R)-2-(2 - hydroxyphenylamino)-5,5-dimethyl-4,5-dihydrothiazole-4-carbo xylic acid mono hydrochloride (Compound 1, 200 mg) was dissolved in / -butanol: water system (1:1 ratio, 40 vol., 8 ml) at RT. The solution was filtered to remove potential seeds, and the filtered solution was frozen in a round bottom flask over a bath of dry ice and acetone. T

Example 5: Pharmacology Overview

Without wishing to be limited by any theory, Compound 1 is a non-metal, orally bioavailable small molecule Reactive Species Decomposition Accelerant (RSDAx) which, in various embodiments, destroys peroxynitrite (PN) and/or hydrogen peroxide. Peroxynitrite and peroxide are powerful oxidants produced under conditions of injury and disease that cause untoward effects via protein nitration and modification of sensory ion channels leading to neuronal sensitization and pain.

In chemical-based assays of peroxynitrite (PN) oxidation, Compound 1 inhibits PN- mediated oxidation of small-molecule organic substrates such as luminol. In cell-based assays of PN- mediated cytotoxicity, Compound 1 is protective. Compound 1 can also catalytically remove peroxynitrite in models of protein nitration (a consequence of peroxynitrite oxidation) and in lactoperoxidase oxidation (mediated by peroxide) under physiological conditions (i.e., neutral pH). Chemically, Compound 1 can also react stoichiometrically with peroxynitrite to form a para-nitro adduct. Without being bound by theory, by targeting and removing peroxynitrite and peroxide, Compound 1 can disrupt the ensuing cascades that lead to hypersensitivity (protein modification, ion channel hyperexcitation) thus providing a long duration event in terms of pain relief.

In various embodiments, Compound 1 is efficacious in in vivo animal models of acute post-incisional hyperalgesia, both prophylactically and palliatively. Compound 1 alleviates allodynia in rat models of diabetic neuropathy (streptozotocin- and methylglyoxal-induced) without brain penetration, thereby avoiding common CNS side effects associated with gabapentin and duloxetine. In various embodiments, Compound 1 does not penetrate the blood-brain barrier (BBB). In various embodiments, less than about 1%, 0.8%, 0.6%, 0.4%, 0.2%, 0.1%, 0.08%, 0.06%, 0.04%, 0.02%, or 0.01% of Compound 1 in blood plasma penetrates the BBB. Compound 1 does not alter normal sensation when given to uninjured animals.

Compound 1 rapidly produces complete reversal of hypersensitivity caused by an injury/insult such as an incision or irritant and upon repeated dosing, reverses allodynia in models of painful diabetic neuropathy. Compound 1 was examined in a variety of pharmacokinetic and metabolism studies. The compound was examined in detail in rat and dog, the species selected for toxicology studies. In vivo, no epimerization of Compound 1 was found using chiral methods. The compound is bioavailable after oral administration with microgram amounts found in the plasma in both rat and dog. Female rats had higher exposure than males, but exposure was similar between the sexes in dogs. In 28-day studies plasma concentrations reach Tmax in 1 hour or less, and half-lives varied from approximately 3 to 8 hours in rat but were more consistent in dogs (tl/2 ~3.5 hours). Plasma concentrations in a 28-day pivotal rat and dog studies were very high, reaching Cmax values of over 100 pg/mL at some doses.

Upon administration, Compound 1 is stable in both plasma and hepatocytes from rat, dog and human. Compound 1 is excreted into urine and feces of rats primarily as a sulfate conjugate. Compound 1 distributes to tissues but not to brain to an appreciable extent. Compound 1 is moderately protein-bound across species. Compound 1 does not inhibit major CYP isoforms (IC50 for CYPs 3A4, 2D6, 1A2, 2C9, 2C19 are all >100 mM). Compound 1 does not inhibit P-gp, OATP1B1, OATP1B3 and OAT1, weakly inhibits OAT3 and modestly inhibits BCRP, which suggests that interactions with transporters or inhibition of CYPs would be minimal or absent at pharmacologically active doses.

Example 6: Distribution of Compound 1

A rat brain distribution study performed in order to determine standard pharmacokinetic parameters and to assess the brain penetration properties of Compound 1 administered orally and intravenously. The compound was rapidly and completely absorbed orally in rats after administration of a 30 mg/kg dose, reaching a peak plasma concentration of 9 pg/mL within 1 hr.

The compound distributed readily in tissues with a steady-state volume of distribution of 1.7 L/kg. Compound 1 was peripherally restricted with a brain-to-plasma concentration ratio of 0.02 1 h after IV administration eliminated at a moderate rate from the systemic circulation. Oral bioavailability of 111% was calculated for the 30 mg/kg oral dose with a terminal half-life of 1.6 hours. A Red Blood Cell (RBC) partitioning showed that Compound 1 poorly partitions into RBC at 60 min post-exposure (KRBC/PL < 0.25) across all species (rat, dog, monkey, human).

Example 7: Clinical Study Protocol for Use of Compound 1 in Treating or Ameliorating Osteoarthritic Pain or Symptoms of Osteoarthritis Clinical Pharmacology

Three studies have been clinically completed to date in healthy subjects up to 55 years of age. A total of 54 subjects have received Compound 1 (maximum of 2000 mg administered as a single oral dose) and 14 subjects received placebo. In the single ascending dose study, 32 subjects were enrolled in four dose cohorts (150, 450, 1100, and 2000 mg Compound 1; subjects were randomized to 6 active and 2 placebo for each dose cohort). In the food effect study, 12 subjects received two single oral doses of 600 mg Compound 1 according to fed or fasting conditions. In the multiple ascending dose study, 24 subjects were enrolled in three dose cohorts (200, 400, and 600 mg dosed orally three times each day for 7 days; subjects were randomized to 6 active and 2 placebo for each dose cohort). The single and multiple Compound 1 doses were safe and well tolerated in healthy subjects.

Compound 1 exhibits linear kinetics with no time- or dose-dependent effect on pharmacokinetic (PK) parameters. Systemic exposure to Compound 1 was dose-proportional across the studied dose range. Decline from peak is characterized by a relatively quick elimination phase with a mean half-life of 1.6 to 3.2 hours. Minimal to no accumulation was observed following multiple-dose administration, and as such, the single-dose PK profile is considered representative of the steady-state profile. The PK profile of Compound 1 following oral administration is best described by a one-compartment model with first-order absorption and first-order elimination. Following oral administration, Compound 1 is rapidly absorbed with a median time to maximum drug concentration (Tmax) of approximately 1-2 hours. Ingestion of a high-fat meal had a small effect on the rate of absorption (approximately 23% reduction in maximum observed [peak] drug concentration (Cmax) and 1 hour delay in Tmax) and had no effect on the extent (area under the plasma concentration-time curve [AUC]) of Compound 1 absorption. Since the relative extent of absorption was unaffected by the presence of a high fat meal, it is anticipated that the slight reduction in Cmax and prolongation of Tmax will be of no clinical significance. In vitro, Compound 1 has shown moderate protein binding in human plasma.

At concentrations of 10 mM, binding was 88%.

Consistent with the nonclinical data, the volume of distribution of Compound 1 in studied subjects was <30 L, which suggests that Compound 1 does not reach beyond the extracellular fluid with limited to no distribution into tissues (intracellularly).

Compound 1 is primarily metabolized in the liver and the major metabolite is a sulfate conjugate. Consistent with preclinical data, following oral administration in healthy subjects, approximately 35% of Compound 1 was excreted unchanged in urine indicating that hepatic metabolism and renal excretion contribute to Compound 1 elimination. Following oral administration in healthy subjects, decline from peak is mono-exponential and is characterized by a rapid elimination phase with rapid clearance (mean CL/F=6.04 to 11.3 L/h) and a short half-life (mean t½=1.6 to 3.2 hours).

According to nonclinical assessments, Compound 1 did not directly inhibit (IC50 values >100 pM) the cytochrome (CYP) isozymes tested (1A2, 2C8, 2C19, 2D6, and 3A4) or transporters (IC50 >600 pM for P-gp, OATP1B1, OATP1B3, OAT1, OCT1, MATE1 and MATE2-K; IC50=174 pM for OAT3; IC50 >30 pM for breast cancer resistant protein [BCRP]).

Study Rationale

Compound 1 has demonstrated efficacy in acute and chronic nociceptive models in rodents and has been shown to be safe and well tolerated in single and multiple ascending dose studies in healthy subjects. The present study is a proof-of-concept study to evaluate the efficacy of Compound 1 as an analgesic for the management of pain associated with OA of the knee and to evaluate the safety, tolerability, and PK profile of Compound 1.

Rationale for Study Design

A randomized, double-blind, placebo-controlled study in subjects with pain who have radiographically confirmed OA of the knee is conducted. The study assesses the efficacy of Compound 1 by comparing active treatment groups receiving either 800 mg Compound 1 BID or 400 mg Compound 1 QID, with a placebo group. In a rat model of OA pain (mono- iodoacetate [MIA] model), a significant reduction in mechanical hyperalgesia was observed for at least 24 hours postdose in Compound 1 treated animals. Guided by the nonclinical MIA animal model, the present study is designed to ascertain the efficacy of Compound 1 in treating pain in a clinical setting.

In a nonclinical MIA rodent model of OA pain, Compound 1 at 100 and 300 mg/kg significantly increased joint compression thresholds, to approximately the same degree as celecoxib. It is unknown, however, whether the response is driven by Cmax or AUC. In the present proof of concept study, the maximum tolerated dose of Compound 1 is being evaluated by testing two dosing regimens (i.e., 800 mg BID or 400 mg QID) to allow the selection of the optimal dosing regimen and better characterization of the exposure-response relationship.

Potential Risks and Benefits

Nonclinical studies in animal models of acute and chronic nociception have demonstrated efficacy (i.e., analgesia) with Compound 1 and that it is safe and well tolerated.

STUDY OBJECTIVES AND ENDPOINTS

The primary objective of the study is to evaluate the efficacy of Compound 1 compared with placebo in the treatment of pain associated with osteoarthritis (OA) of the knee. The primary endpoint is change from Baseline to Week 4 in the weekly average of the daily average Numeric Rating Scale (NRS) pain intensity scores.

The secondary objective of the study is to evaluate the efficacy of Compound 1 compared with placebo in the treatment of pain associated with OA of the knee. The key secondary endpoints include:

• Patient Global Impression of Change (PGIC) at Week 4 with reference to baseline status

• Proportion of subjects who are responders as defined by 30% and 50% reductionfrom Baseline to Week 4 in the weekly average of the daily average NRS pain intensity scores

Additional secondary endpoints include:

• Change from Baseline to Week 4 in: o Weekly average of the daily worst NRS pain intensity scores o Brief Pain Inventory-Short Form (BPI-sl) o 12-item Short Form Survey (SF- 12)

The exploratory objective of the study is to evaluate the use of rescue medication in subjects with pain associated with OA of the knee treated with Compound 1 compared with placebo. The exploratory endpoints are:

• Comparison of average daily rescue medication use

• Hospital Anxiety and Depression Scale (HADS)

The safety objective of the study is to evaluate the safety and tolerability of Compound 1 compared with placebo in the treatment of pain associated with OA of the knee. Safety is evaluated by analyses of the following:

• Treatment-emergent adverse events (TEAEs)

• Vital signs

• Electrocardiograms (ECGs)

• Physical examination results

• Clinical laboratory tests

• Columbia-Suicide Severity Rating Scale (C-SSRS)

Pharmacokinetic (PK) and /Pharmacodynamic (PD) Objectives

The PK objective of the study is to characterize the PK profile of Compound 1 in subjects with pain associated with OA of the knee. The PK endpoints of the study are:

• Plasma concentrations of Compound 1 using sparse sampling on the foil owing study days:-Baseline (Week 0), Week 1, Week 2, and Week 4 (EOT)/ET

• Compound 1 PK parameters determined using a population PK approach

The pharmacokinetic/pharmacodynamic (PK/PD) objective of the study is to characterize the exposure-response relationship using appropriate modelling and simulation methods. • Guided by exploratory analyses, appropriate Compound 1 exposure-response relationship: o for efficacy using the primary endpoint o for safety using the most frequent and other relevant TEAEs

STUDY DESCRIPTION

The study is a randomized, double-blind, placebo-controlled, parallel-group study to evaluate the efficacy and safety of Compound 1 in subjects with pain associated with radiographically confirmed OA of the knee. The study compares active treatment groups, receiving either 800 mg Compound 1 BID or 400 mg Compound 1 QID, with a placebo group. The Sponsor, subjects, and Investigators are blinded to treatment assignment. Up to approximately 40 sites in the United States (US) screen approximately 480 subjects and approximately 240 subjects are planned for randomization (80 subjects per treatment group). The duration of participation for individual study subjects is approximately 13 weeks, consisting of a screening period of up to 4 weeks, a 7-day baseline pain assessment period, a 4-week double-blind treatment period, and a safety follow-up period of approximately 30 (+4) days.

The study periods are:

• Screening: up to 4 weeks

• Baseline Pain Assessment: a 7-day period during which baseline pain assessments are recorded for 7 days. Additional 3- day window may be added, if needed.

• Double-blind treatment: 4 weeks

• Safety follow-up: approximately 7 days after end of treatment (EOT)/ early termination (ET) and approximately 30 days after the last dose of study drug

The study start date is defined as the date the first subject is enrolled, which is the date the first subject is randomized. The primary completion date is the last date that subject data was collected for the primary outcome measure. The study completion date is defined as the last date that subject data was collected for the primary outcome measure, secondary outcome measure(s), and adverse events, which includes the safety follow-up telephone call visit. Procedures for when a subject is lost to follow-up are provided herein. The study schematic is presented in FIG. 1 and the schedule of assessments is provided in Table 2.

Table 2: Schedule of Events and Assessments forCompound 1

Height is measured only at the Screening visit, and BMI is calculated based on height and weight measurements at Screening. Weight is also measured at any unscheduled visit.

A single 12-lead ECG is performed at Screening, at Baseline (Week 0) both predose and at 1 hour postdose (the first dose of the day), Week 1 and Week 2, and EOT/ET. A 1-hour window is permitted for the predose ECG and a 20-minute window is permitted for the postdose ECGs. Electrocardiograms should be performed before blood sampling or at least 30 minutes after blood sampling.

Applicable to women of childbearing potential. A serum pregnancy test should be performed at Screening and a urine test must be performed at all other designated visits.

At Baseline, urine drug screen is performed using a dipstick test which must be negative for any non-permitted medications or drugs in order for the subject to continue in the study.

COVID-19 diagnostic PCR test at Screening.

Randomization visit cannot occur until there is confirmation from the central reader that there are no exclusionary findings.

Subjects are instructed on the use of and complete electronic clinical outcome assessments using handheld devices during the study. An eDiary is used to record pain scores, compliance with ingestion of study medication, and use of rescue medication.

A PK sample (approximately 4 mL) should also be taken from subjects who experience SAEs or AEs leading to discontinuation, as soon as possible after the occurrence of the event.

A predose PK blood sample must be collected before administration of study drug. A postdose PK blood sample will be collected at the end of ECG assessment approximately 1 hour after study drug administration.

PK samples at Visits 4, 5, and 6 will be collected at one of the following time intervals: 1) 2-5 hours after morning dosing OR 2) 6-9 hours after morning dosing OR 3) 10-12 hours after morning dosing. Every effort should be made to collect the PK samples at distinct time intervals during Visits 4, 5, and 6. However, if the interval is the same across these visits, then the collection time should vary within that interval.

At study visits, pain assessments should be performed before blood sample collection, ECG, and other procedures.

Participant Scorecard is viewed by the subject and reviewed by the Investigator at the designated study visits. The Investigator or designee, will acknowledge the scorecard review on the training platform, aLeam.

ASR and PPR training at Visits 4, 5, and/or 6 is on an as needed basis and the need for training will be determined by Participant Scorecard intervention recommendations.

Record rescue medication use in diary.

The Investigator may perform any additional evaluations deemed to be clinically indicated. If an unscheduled visit is required for safety reasons, a 12-lead ECG and all appropriate clinical laboratory tests are to be performed.

Vital signs will include body temperature, resting respiration rate, supine and standing systolic and diastolic blood pressure, and pulse rate. Blood pressure and pulse rate will be measured after the subject rests for 5 minutes in the supine position. The subject will then be asked to stand and blood pressure and pulse rate will be taken after standing for 1 minute and then again after 3 minutes. Subjects unable to stand may be assessed while sitting upright. The same position and arm should be used each time vital signs are measured for a given subject.

Screening Period (Up to 4 Weeks)

During the Screening period, subjects are assessed for study eligibility. All subjects must have radiographically confirmed OA of the knee, including review of imaging and confirmation of a Kellgren-Lawrence (K-L) score of 2 or 3. Subjects who have had an X-ray of the index knee within 12 weeks of Screening may provide a historical image for central reading to confirm eligibility, or imaging can be done during Screening at protocol-trained radiological sites. Randomization visits cannot occur until there is confirmation from the central reader that there are no exclusionary findings on the knee joint images. The index knee is defined as the most painful knee at Screening.

Prohibited analgesic medications must be discontinued during the Screening period. Investigators must not withdraw a subject's prohibited medication other than analgesics solely for the purpose of enrolling them into the study. Medications are discontinued only if it is deemed clinically appropriate to do so and in consultation with the prescribing physician.

All pain medication, except for the study-provided rescue medication (acetaminophen), is discontinued 7 days or 5 half-lives, whichever is longer, prior to the Baseline Pain Assessment Period. In the event of inadequate pain relief, acetaminophen may be taken with a maximum daily dose of 2500 mg. Rescreening of a subject is allowed, with the approval of the Medical Monitor.

Baseline Pain Assessment Period (1 Week)

Following eligibility at screening, subjects complete a Baseline Pain Assessment Period that occurs approximately 7 days before randomization; an additional 3-day window may be added, if needed. During the Baseline Pain Assessment Period, subjects are instructed in the use of a handheld device (electronic diary [eDiary]) to record their daily pain scores and rescue medication use. Compliance with recording of pain score; and use of rescue medication is assessed for continued study eligibility. Subjects are encouraged to refrain from taking rescue medication during the Baseline Pain Assessment Period and for at least 24 hours prior to the start of the study visits. Subjects who enter the Baseline Pain Assessment Period are not allowed to rescreen.

Treatment Period (4 Weeks)

At Baseline (Week 0), eligible subjects are randomly assigned in a 1:1:1 ratio to receive Compound 1 800 mg BID, Compound 1 400 mg QID, or placebo, according to a randomization schedule. Randomization is stratified by sex and baseline K-L score (2 or 3). All efficacy assessments are completed and a PK blood sample is taken at the Baseline visit prior to administration of the first dose of study drug (Table 2). Subjects continue daily entry into the eDiary of pain scores, compliance with ingestion of study medication, and rescue medication use from Week 0 through to Week 4/EOT/ET. Subjects receive their first dose at the study site after all Baseline assessments havebeen completed and a PK blood sample is taken approximately 1 hour after dosing. Dosing is four times a day.

During the treatment period (Week 0 through Week 4), subjects are permitted to use only acetaminophen as rescue medication. Subjects record their use of acetaminophen in their eDiary. Subjects are encouraged to refrain from acetaminophen use for at least 24 hours prior to the start of study visits in order to minimize the confounding effects of the rescue medication on efficacy measurements. A PK sample is taken at each study visit according to the schedule described herein. At the Week 4 visit, end of treatment (EOT) procedures are completed. Safety Follow-up Period (30 Days)

Safety will be further assessed during a follow-up visit to occur in the clinic approximately 7 (±3) days after EOT/ET procedures. During this in-clinic visit pain intensity, adverse events (AEs), and concomitant medications will be assessed since the EOT/ET. Then, a follow-up telephone call occurs approximately 30 (+4) days after the last dose of study drug to assess AEs and concomitant medications. The study schematic is presented in FIG. 1.

SUBJECT ELIGIBILITY AND WITHDRAWAL CRITERIA

To be eligible for this study, subjects must meet all of the inclusion criteria and none of the exclusion criteria.

Inclusion Criteria

A subject must meet all of the following inclusion criteria to be eligible for participation in the study:

1. Male or female subjects >18 and <65 years of age at the time of Screening

2. Able to understand and provide signed informed consent

3. Has a body mass index (BMI) <39 kg/m ² at Screening

4. Confirmed history of pain associated with OA in the index knee

5. Clinical diagnosis of OA in at least one knee joint (i.e., the index knee) based on the American College of Rheumatology Criteria with radiographic evidence of OA (K- L score of 2 or 3) at Screening

Note: K-L scores of 1 or 4 are exclusionary

6. Willing to maintain current activity and exercise levels throughout the study

7. Willing and able to comply with clinic visits and study-related procedures

8. Consent to allow all radiographs and medical/surgical/hospitalization records of care received elsewhere to be shared with the Investigator and third parties who examine the images (i.e., central x-ray reader)

9. Negative urine drug screen result at Screening, Baseline Pain Assessment Period, and Baseline. A positive urine drug test for a prescribed medication that is permitted at Screening , but not in the study, is acceptable if it has been prescribed. The subject needs to washout from this medication, if appropriate, and have a negative screen for this medication prior to randomization. Investigators must not withdraw a subject's prohibited medication other than analgesics solely for the purpose of enrolling them into the study. Medications are discontinued only if it is deemed clinically appropriate to do so and in consultation with the prescribing physician.

10. Must have a negative COVID-19 diagnostic polymerase chain reaction (PCR) test at Screening. Not planning to receive a COVID-19 vaccine during Screening through 30 days of the last dose of study drug. If the subject has received a COVID-19 vaccine, they must be fully vaccinated at least

1 week before the Screening visit and be symptom free.

11. If the subject is male, the subject and his partner must use a highly effective form of contraception (i.e., double-barrier method which includes a condom plus diaphragm with spermicide or condom plus spermicide) at the time of Screening and for at least 30 days after the last dose of study drug. If subjects have had a vasectomy, they must still use a condom.

Subjects must also agree to not donate sperm for the duration of the study and for at least 30 days after the last dose of study drug

12. If the subject is female, she must not be pregnant or breastfeeding. She must also be of non-childbearing potential (defined as either surgically sterilized or at least 1 year postmenopausal) OR must agree to use TWO clinically acceptable methods of contraception for at least 30 days prior to Day -1, throughout the entire study, and for at least 30 days following completion of the study.

Acceptable methods of contraception include the following: a. A barrier method (condom, diaphragm, or cervical cap) with spermicide b. Hormonal contraception, including oral, injectable, transdermal, or implantable methods c. Intrauterine device (IUD)

Only one of the two clinically acceptable methods can be a hormonal method.

All female subjects of childbearing potential must have a negative serum human chorionic gonadotropin (hCG) pregnancy test at Screening and a negative urine pregnancy test at Baseline.

Inclusion Criteria Specific to Baseline Pain Assessment Period

13. Baseline Pain Assessment Period weekly average daily pain score >4

14. Has no more than 1 day with a pain score of 10 during the Baseline Pain Assessment Period

15. Has a standard deviation of <1.6 for average daily pain score diary entries during the Baseline Pain Assessment Period

16. Able to complete logging of pain scores for at least 6 of the last 7 days of the Baseline Pain Assessment Period

Exclusion Criteria

A subject must meet none of the following exclusion criteria to be eligible for the study:

Medical Conditions

1. Pain anywhere else in the body which is greater than or equal to OA pain in the index knee, or likely to interfere with subject's assessment of pain throughout the study, as judged by the Investigator

2. History or presence on imaging of knee arthropathy (osteonecrosis, subchondral insufficiency fracture, rapidly progressive OA type 1 or type 2), recent fall, injury, or trauma affecting the index knee, ligament tear, neuropathic joint arthropathy, knee dislocation (patella dislocation is eligible), extensive subchondral cysts, Baker's cyst, evidence of bone fragmentation or collapse, or primary metastatic tumor with the exception of chondromas, or pathological fractures during the Screening Period

3. History or presence at Screening of non-OA inflammatory joint disease (e.g., rheumatoid arthritis, lupus erythematosus, psoriatic arthritis, pseudo-gout, gout, spondyloarthropathy, joint infections within the past 5 years, Paget's disease of the spine, pelvis, or femur, neuropathic disorders, multiple sclerosis, fibromyalgia, tumors or infections of the spinal cord, or renal osteodystrophy) or any condition that would interfere with the rating of OA pain

4. Recent arthroscopic surgery within 1 month of Screening; or has any planned surgery or procedure during the study

Concomitant Treatments

1. Use of monoamine reuptake inhibitors, tricyclic antidepressants, anticonvulsants, and/or serotonin norepinephrine reuptake inhibitors within 4 weeks prior to Screening.

Unwilling to discontinue current use of analgesic medication following Screening and to adhere to study requirements for rescue treatments (study-provided acetaminophen to be taken as needed with a maximum daily dose of 2500 mg), including, but not limited to, non-steroidal anti-inflammatory drugs (NSAIDs), opioids, selective cyclooxygenase 2 inhibitors, acetaminophen, or combinations thereof, within7 days or five half-lives of the drug prior to the Baseline Pain AssessmentPeriod, whichever is longerNote: only the study-provided rescue medication, i.e., acetaminophen, is allowed for OA pain in the knee; aspirin, at a dose of up to 81 mg per day, is allowed for prophylaxis of coronary and cerebrovascular events if stable for 30 days prior to Screening and the dose is expected to remain the same throughout the duration of the study.

2. Use of immediate- or extended-release or controlled-release opioids (e.g., oxycontin), transdermal fentanyl, or methadone within 3 months prior to Screening

3. Use of opioids, for the treatment of pain other than OA of the knee, with a morphine equivalent dose of >30 mg per day for more than 2 days per week within 1 month prior to Screening

4. Use of systemic (i.e., oral) corticosteroids or intra-articular corticosteroids in any joint within 30 days prior to the screening visit (topical, intranasal, and inhaled corticosteroids are permitted)

5. Intra-articular injection of any approved (i.e., hyaluronic acid and corticosteroids) or unapproved treatments (e.g., platelet-rich plasma, capsaicin) into the index knee within 3 months of Screening

6. Physical/occupational/chiropractic therapy for the lower extremities or acupuncture for the lower extremities within 30 days of Screening, or the need for such therapy during the study

Medical History, Laboratory Studies, Vital Signs, and Electrocardiograms

1. Has current evidence, or history within the previous 12 weeks prior to Screening, of a serious and/or unstable psychiatric, neurologic, cardiovascular, respiratory, gastrointestinal, renal, hepatic, hematologic, endocrinologic, or other medical disorder, that in the judgment of the Investigator and/or Medical Monitor would jeopardize the safe participation of the subject in the study

2. Had a malignancy in the last year, with the exception of nonmetastatic basal cell of the skin or localized carcinoma in situ of the cervix

3. Has clinically significant laboratory abnormalities at Screening that in the judgmentof the Investigator or Medical Monitor would jeopardize the safe participation of the subject in the study

4. Has moderate or severe renal impairment (estimated glomerular filtration rate [eGFR] <60 mL/min/1.73 m ² from screening clinical laboratory tests) Has an ECG QTcF result >480 ms at Screening or Baseline Has a history of uncontrolled hypertension, as defined by: a. Systolic blood pressure >180 mmHg or diastolic blood pressure >100 mmHg at Screening or Baseline b. Systolic blood pressure of 160-179 mmHg or diastolic blood pressure of 100- 109 mmHg at Screening or Baseline, AND a history of end-organ damage (including history of left ventricular hypertrophy, heart failure, angina, myocardial infraction, stroke, transient ischemic attack, renal failure, peripheral arterial disease and moderate to advanced retinopathy [hemorrhages or exudates, papilledema]) c. Known clinical diagnosis of orthostatic hypotension d. Evidence of orthostatic hypotension at Baseline, defined as a decrease in systolic blood pressure >20 mmHg or diastolic blood pressure >10 mmHg after transitioning from the supine position (after resting for 5 minutes) to standing at 1 or 3 minutes. Subjects unable to stand may be assessed while sitting upright. Congestive heart failure with New York Heart Classification of stage III or IV (Appendix A) Transient ischemic attack or cerebrovascular accident within the past 12 months priorto Screening, or myocardial infarction, or acute coronary syndromes within the past

6 months prior to Screening Is suicidal at Screening or Day -1 as defined below: a. An answer of "yes" to C-SSRS questions 4 or 5 (current or over the last 6 months); OR b. Has attempted suicide within 1 year prior to Screening; OR c. Is actively suicidal in the Investigator's judgment Beck Depression Inventory-II (BDI-II) score >29 at Screening Has a history of uncontrolled diabetes mellitus (DM), Type 1 or Type 2 DM requiring insulin treatment, or glycosylated hemoglobin (HbAlc) >7.0% at Screening Known history of human immunodeficiency virus (HIV) infection Known history of infection with hepatitis B virus. Subjects with a history of hepatitis B are eligible if there is documentation of a negative test for hepatitis B surface antigen and a positive test for antibodies to the hepatitis B virus surface antigen

14. Known history of infection with the hepatitis C virus. Subjects with a history of hepatitis C are eligible if there is documentation of a negative hepatitis C virus RNA test

15. Has a known or suspected history of drug abuse or a recent (within the last 5 years) history of alcohol abuse

16. Use of medicinal or recreational marijuana or cannabidiol (CBD) within 1 month prior to Screening. The use of these substances are not allowed throughout the study

Other Criteria

17. Subject is unlikely to be able to swallow double-blind study drug (i.e., swallowing tablets 4 times per day, including two tablets at the first and third dosing)

18. Subject is unwilling or unable to comply with the use of the handheld devices

19. Has a significant sensitivity or allergic reaction to Compound 1 or its excipients, or rescue medication

20. Has participated in or is participating in a clinical research study evaluating Compound 1 or has received anotherinvestigational product within 30 days or 5 half-lives, whichever is longer, prior to Screening

21. Is an employee or is a family member of an employee of AcadiaPharmaceuticals Inc. or the clinical research site or the CRO administering this study

Screen Failures

Rescreening of a subject is allowed, with the approval of the Medical Monitor. Subjects may be rescreened following a COVID-19 infection as long as they have no sequelae from COVID-19 infection, per Exclusion Criterion 12. Subjects who enter the Baseline Pain Assessment Period are not allowed to rescreen. The minimum information that is captured for screen failures includes date informed consent is signed, demography, screen failure details, and any adverse event (AE)/serious adverse event (SAE).

Subject Withdrawal of Consent

In accordance with the Declaration of Helsinki and other applicable regulations, a subject has the right to withdraw from the study at any time, and for any reason, without prejudice to his or her future medical care. If the subject decides to withdraw consent from all components in the study, this must be documented and no additional assessments are performed. If the subject wants to discontinue treatment and agrees to the evaluations specified at the EOT/ET visit and/or at safety follow-up (whichever is applicable), as outlined in Table 2, the agreed assessments should be conducted. The subject's reason for wanting to discontinue treatment and the agreement to continue with the applicable assessments for study termination must be documented.

Subject or Study Discontinuation

Subjects may be discontinued from the study for a number of reasons, including, but not limited to, those listed below:

AE

Death

Lack of efficacy

Lost to follow-up

Non-compliance with study drug

Investigator decision

Pregnancy

Protocol deviation

Study terminated by sponsor

Use of prohibited medication

Withdrawal of consent by subject

Other

If at any time the C-SSRS results for a given subject reveal potential suicidality, then the Investigator should assess the clinical significance of such results. If a clinically significant risk of suicidality is identified for a subject, then the Investigator should discontinue the subject and implement appropriate treatment as set forth herein.

Individual subject and aggregate safety data will be reviewed regularly throughout the study to determine whether the study should be stopped, modified, or continued based on the review of cumulative data. This review will include analysis of similar clinically significant laboratory findings/abnormalities, ECG abnormalities, vital sign abnormalities and AE’s among subjects in order to assess all potential risks from blinded investigational product. The Sponsor reserves the right to discontinue the study at any time for any reason. Such reasons may be any of, but not limited to, the following:

• Occurrence of AEs unknown to date in respect of their nature, severity, and duration or the unexpected incidence of known AEs

• Frequently-occurring, similar serious adverse events that increases risk for all subjects from continued participation in the study

• Frequently-occurring, similar clinically significant laboratory findings/abnormalities,

ECG abnormalities, and/or vital sign abnormalities that increases risk for all subjects from continued participation in the study

• Medical, ethical, or business reasons affecting the continued conduct of the study

Regulatory authorities also have the right to terminate the conduct of the study in their region for any reason. If the study is terminated for any reason, subjects remaining in the study return to standard of care.

Discontinuation of Study Drug for Individual Subjects

The Investigator and Medical Monitor will review all laboratory, ECG, and related safety data regularly throughout the study for all individual subjects in order to determine whether any individual subject may continue to safely participate in the study. In general, either the Investigator or the Medical Monitor may discontinue the subject from the study at any time when any specific laboratory or ECG data change from Baseline indicates that the subject is placed at increased risk from continued participation in the study. In rare instances, it may be necessary for a subject to permanently discontinue study drug. Study drug stopping criteria are described below. If a subject experiences any of the below events, it must be documented as an AE.

Liver Chemistry Stopping Criteria

Discontinuation of study drug for abnormal liver tests is required by the Investigator when a subject meets one of the conditions outlined below. The Investigator can discontinue study drug in the presence of abnormal liver chemistries not meeting protocol-specified stopping rules if they believe that it is in best interest of the subject.

• Alanine aminotransferase (ALT) or aspartate aminotransferase (AST) >8 ^c upper limit of normal (ULN)

• ALT or AST >5 ^c ULN for more than 1 week

• ALT or AST >3 ^c ULN and total bilirubin (TBL) >2 ^c ULN • ALT or AST >3 ^c ULN with the appearance of fatigue, nausea, vomiting, right upper quadrant pain or tenderness, fever, rash, and/or eosinophilia (>5%)

• Creatine kinase (CK)/creatine phosphokinase (CPK) >5 ^c ULN for more than 1 week

Cardiovascular-Related Stopping Criteria

If a clinically significant finding of orthostatic hypotension, bradycardia, or change in QTcF, as defined below, is identified after enrollment, the Investigator or qualified designee and Medical Monitor will determine if the subject can continue in the study and if any change in subject management is needed.

• Orthostatic hypotension - decrease in systolic blood pressure (SBP) >20 mmHg or diastolic BP (DBP) >10 mmHg after transitioning from the supine position (after resting for 5 minutes) to standing at 1 or 3 minutes with or without symptoms such as light headedness or dizziness and not explained by dehydration, illness, or medications

• Significant bradycardia, defined as heart rate of <45 beats per minute (BPM) on an ECG, or pulse decrease of >25% from Baseline with resulting heart rate <60 BPM

• QTcF result >470 ms for males and >480 ms for females or QTcF increases >60 ms from Baseline

Adverse Event Stopping Criteria

If a clinically significant finding of any below-mentioned or any other medically-concerning AE that is considered by the Investigator and Sponsor to be causally related to study drug is identified after enrollment, the Investigator or qualified designee and Medical Monitor will determine if the subject can continue in the study and if any change in subject management is needed.

• life-threatening event

• immediate drug reaction (e.g., Stevens-Johnson syndrome)

• QT prolongation

• acute renal insufficiency

• cardiopulmonary arrest

Handling of Subject Discontinuation During the Treatment Period

Unless the subject has withdrawn consent from all components of the study, every reasonable effort should be made to complete Week 4 (EOT)/ET and all safety follow-up assessments (as outlined in Table 2) for all subjects who discontinue prematurely during the treatment period of the study. All information are reported on the applicable pages of the electronic case report form (eCRF).

If a subject is discontinued from the study because of an AE, every reasonable attempt should be made to follow and appropriately treat (or refer for treatment) the subject until the AE resolves or until the Investigator deems the AE to be chronic or stable. For subjects who continue to be followed for safety, SAEs should continue to be reported as described herein. All SAEs continue to be followed and appropriately treated until such events have resolved or the Investigator deems them to be chronic or stable.

Subject Lost to Follow-up

A subject is considered lost to follow-up if they fail to attend a scheduled visit and are unable to be contacted by the study site. Every reasonable effort should be made to contact the subject and includes a minimum of three documented phone calls and, if necessary, a certified letter to the subject's last known mailing address or local equivalent methods. All contact attempts are to be documented in the source documents.

Prior and Concomitant Therapy

All medications used from study screening until completion of the second safety follow-up telephone call contact are to be recorded.

Prior Medication

Prior medication is defined as any medication with stop dates prior to the date of the first dose of study drug.

Concomitant Medication

Concomitant medication is defined as any medications taken after the date of the first dose of study drug through to the second follow-up telephone call. In order to ensure that appropriate concomitant therapy is administered, it is essential that subjects be instructed not to take any medication without prior consultation with the Investigator (unless the subject is receiving treatment for a medical emergency). The Investigator may prescribe appropriate medication to treat AEs. Drugs that confound the potential analgesic response and are prohibited include:

• monoamine reuptake inhibitors, antidepressants, anticonvulsants, and/or serotonin norepinephrine reuptake inhibitors

• Analgesics (other than study -provided rescue medication, i.e., acetaminophen), including NSAIDs, opioids, selective cyclooxygenase 2 inhibitors, acetaminophen, or combinations thereof

Note: only the study-provided rescue medication, i.e., acetaminophen, is allowed for OA pain in the knee; aspirin, at a dose of up to 81 mg per day, is allowed for prophylaxis of coronary and cerebrovascular events if stable for 30 days prior to Screening and the dose is expected to remain the same throughout the duration of the study.

• systemic corticosteroids or intra-articular corticosteroids

• intra-articular injection of any approved (i.e., hyaluronic acid) or unapproved treatments (e.g., platelet-rich plasma, capsaicin)

Permitted, Restricted, and Prohibited Medications

Prohibitions and restrictions for concomitant medications should be followed between the initial screening visit and Week 4 (EOT)/ET. Permitted concomitant medications should remain at a stable dose throughout the study. Subjects who require current treatment with a prohibited medication are withdrawn from the study. Subjects who have taken a prohibited medication during the study are withdrawn from the study unless the prohibited medication has been discontinued, and withdrawal from the study presents an unacceptable medical risk to the subject.

The justification to allow the subject who has taken a prohibited medication to continue in the trial is made by the Sponsor/Medical Monitor, with medical input from the Investigator, and is documented. If a subject is allowed to remain in the trial, this is reported as a major protocol deviation and not a waiver.

Rescue Medications, Treatments, and Procedures

Subjects are encouraged to refrain from taking rescue medication during the Baseline Pain Assessment Period and for at least 24 hours prior to the start of the study visits in order to minimize the confounding effects of the rescue medication on efficacy measurements. The total daily dose of acetaminophen should not exceed 2500 mg (5 tablets).

INVESTIGATIONAL PRODUCT The investigational products are Compound 1 400 mg tablets or matching placebo. Placebo tablets are size- and color-matched to the Compound 1 tablets. In order to maintain the double-blind design of the study, tablets are administered orally four times per day for 4 weeks.

Doses to be studied are:

• Compound 1 800 mg total dose delivered two times a day (provided as 2x400 mg Compound 1 tablets)

• Compound 1 400 mg total dose delivered four times a day (provided as 1 x400 mg Compound 1 tablet)

• Placebo, size- and color-matched to Compound 1 tablets

Formulation, Appearance, Packaging, and Labeling

The Sponsor supplis Compound 1 400 mg tablets and matching placebo tablets provided in blister cards. In various embodiments, Compound 1 is a white to off-white powder. In various embodiments, Compound 1 400 mg tablets include the active compound (Compound 1) and the following excipients: microcrystalbne cellulose, polyvinylpyrrolidone, croscarmellose sodium, silicon dioxide, magnesium stearate, Opadry ^® II 85F18546 film coating. In various embodiments, the drug product is formulated with standard pharmaceutical excipients at 400 mg strength (454.5 mg of Compound 1). Placebo tablets contain all of the same excipients as Compound 1 400 mg tablets but do not contain any Compound 1. Compound 1 tablets and placebo tablets are manufactured under Good Manufacturing Practices.

Product Storage and Stability

In various embodiments, the investigational product is stored between 20°C to 25°C (68°F and 77°F); and in some embodiments excursions permitted between 15°C to 30°C (59°F to 86°F) [See USP controlled conditions] in a secure area with restricted access and according to local and national regulations.

Rescue Medication

The sponsor provides acetaminophen 500 mg tablets. The bottles of acetaminophen are labelled with a protocol-specific label regarding the maximum allowable daily dose for the study. All rescue medication is stored per commercially labelled conditions. Dosing and Administration

At Baseline (Week 0), eligible subjects are randomly assigned in a 1:1:1 ratio to receive Compound 1 800 mg BID, Compound 1 400 mg QID, or placebo (Table 3). In order to maintain the double-blind design of the study, all subjects take the same number of tablets per day. Dosing is to occur in the morning (2 tablets), noon (1 tablet), evening (2 tablets), and night (1 tablet) and should occur at the same time each day over the duration of the study.

The first dose of study drug is administered in the clinic, subjects are instructed on administration of study drug, and subjects are sent home with blinded study drug in blister cards.

Table 3: Blinded Daily Dosing Regimen

Abbreviations: P=Compound 1 placebo tablet; X=Compound 1 400 mg tablet

Method of Assigning Subjects to Treatment Groups

At Baseline (Week 0), eligible subjects who meet inclusion and do not meet exclusion criteria are randomized in a 1:1:1 ratio to receive Compound 1 800 mg BID, Compound 1 400 mg QID, or placebo, according to a randomization schedule.

Blinding

Treatment assignments are blinded to all study subjects, Investigators, site personnel, and Sponsor personnel. In the event of a potential SUSAR, in accordance with current health authority guidance, treatment assignments for the affected subject may be unblinded to a controlled group of the Sponsor's Safety and/or Regulatory personnel for reporting purposes; the site personnel, Investigators, and monitors remain blinded in this situation. Details regarding medical emergency unblinding procedures are provided herein.

Study Drug Compliance

The Investigator or designated study center personnel maintain a log of all study drug dispensed and returned during the study. Study drug supplies for each subject are inventoried and accounted for throughout the study to verify the subject's compliance with the dosage regimen. Subjects are counseled regarding compliance at every visit. Subjects who have <80% or >120% compliance may be discontinued from the study. If a subject shows significant undercompliance (<80%) between any two scheduled visits, the Medical Monitor should be notified to determine if the subject remains eligible for the study and whether the incident should be considered a protocol deviation. If a subject misses a dose, they should not take an extra dose.

Overdose

An overdose is a deliberate or inadvertent administration of a treatment (i.e., study drug or rescue medication) at a dose higher than the maximum recommended dose per protocol. It must be reported, irrespective of outcome, even if toxic effects were not observed. All events of overdose are to be captured as protocol deviations.

Investigational Product and Rescue Medication Accountability Procedures

The Investigator or designee keeps current and accurate records of the study drug product dispensed, used and returned for each subject to assure the regulatory authority and the Sponsor that the study drug is being handled appropriately. Any study drug and rescue medication supplied is for use in this study only and should not be used for any other purpose. A clinical research associate (CRA) is responsible for monitoring product accountability procedures and tablet counts by the site staff. Site staff keeps current records of rescue medication dispensed, used, and returned for each subject to assure the regulatory authority and the Sponsor that the rescue medication is being handled appropriately.

At the conclusion of the study, final study drug reconciliation is conducted at the site. Final study drug accountability documentation is maintained at both the site and at the Sponsor. Any remaining unused study drug and rescue medication and all used and unused packaging is sent back to the Sponsor's designee for destruction. Documentation of study drug destruction is recorded and maintained by both the Sponsor and the Sponsor's designee.

STUDY PROCEDURES

Study specific procedures are detailed below. All assessments are completed according to the schedule described in Table 2. Every effort should be made to complete the required procedures and evaluations at the designated visits and times. Remote Assessments or Visits

Circumstances may arise (e.g., pandemic, natural disaster, or political upheaval) when a study visit at the clinic may not be possible. In those cases, study visit assessments may be performed at the subject's place of residence by site staff either in person, or via video technology or telephone where possible. The Investigator must contact the Medical Monitor in advance for approval with the plan. Sites must keep a log to identify details of all visits that are performed remotely. The location of the collected assessments should be captured in the source documents.

Screening Assessments

All screening assessments must be completed and reviewed to confirm that potential participants meet all eligibility criteria. The Investigator maintains a screening log to record details of all participants screened and to confirm eligibility or record reasons for screening failure, as applicable.

Medical and Medication History

A complete medical, medication (including past OA treatments), and surgical history are obtained from each potential subject at the Screening visit. Demographic information, including date of birth, sex, race, and ethnicity are recorded as well. Any new medical condition reported with a start date after the ICF has been signed is captured as an AE. Subjects may be asked to provide pharmacy or medical records to substantiate the medication history. Any medication reported as taken on or after Baseline (Week 0) is captured as concomitant medication.

Beck Depression Inventory-II

The BDI is a 21 -item, self-report rating inventory that measures characteristic attitudes and symptoms of depression (Beck et al. 1961). Like the BDI, the BDI-II also contains

21 questions, each answer being scored on a scale value of 0 to 3. Higher total scores indicate more severe depressive symptoms. The standardized cutoffs used differ from the original:

• 0-13: minimal depression

• 14-19: mild depression

• 20-28: moderate depression • 29-63: severe depression

The BDI-II is completed at Screening.

Baseline Pain Assessment Period

Approximately 7 (+3) days prior to randomization, subjects complete a Baseline Pain Assessment Period. During this period, subjects are instructed in the use of a handheld device eDiary) to record their daily pain scores and use of rescue medication. Prior to beginning the Baseline Pain Assessment Period, to ensure accurate reporting of OA knee pain, subjects receive Accurate Symptom Response Training (ASR) and Placebo Response Reduction (PRR) Training. Compliance with recording of pain score and use of rescue medication is assessed for continued study eligibility.

Accurate Symptom Reporting Training

The Accurate Symptom Reporting (ASR) training instructs subjects how to report pain scores accurately and reliably, and on the proper use of pain scales, with the aim of increasing the reporting accuracy of subject pain. Subjects receive training via eDiary at Visit 1 and Visit 3; additional training may be performed at Visits 4, 5, and/or 6 on an as needed basis and the need is determined by Participant Scorecard recommendations.

Placebo Response Reduction Training

The Placebo Response Reduction (PRR) training teaches the subject about the appropriate expectations of personal benefit while participating in a clinical trial. The purpose is to provide subjects with truthful information that neutralize the typically excessive expectations that drive high placebo responses in clinical studies. Subjects receive training via eDiary at Visit 1 and Visit 3; additional training may be performed at Visits 4, 5, and/or 6 on an as needed basis and the need isdetermined by Participant Scorecard recommendations.

Efficacy Assessments

Numeric Rating Scale of Pain Intensity

A 0 to 10 NRS is used to assess the subject's pain throughout the study. Subjects are required to assess and record daily in the eDiary their knee pain intensity and daily use of rescue medication. Subjects are rating both the average daily pain as well as their worst daily pain. Knee pain intensity is assessed by describing their knee pain at the present time from 0 to 10 where "0" means "no pain at all" and "10" means "the worst pain imaginable". Pain intensity assessments are to be recorded in the evening prior to their 4 ^th dose of the day.

Subjects are encouraged to refrain from acetaminophen use for at least 24 hours prior to the start of study visits in order to minimize the confounding effects of the rescue medication on efficacy measurements. At study visits, pain assessments should be performed before blood sample collection, ECG, and other procedures.

Patient Global Impression of Change

The self-report measure Patient Global Impression of Change (PGIC) reflects a subject's belief about how their pain has changed since start of study treatment. PGIC is a 7- point scale depicting a subject's rating of overall improvement. Subjects rate their change as "very much improved," "much improved," "minimally improved," "no change," "minimally worse," "much worse," or "very much worse". The PGIC is completed at Week 1, Week 2, and Week 4 (EOT)/ET.

Brief Pain Inventory-Short Form

The BPI is a self-report measure used to assess the severity of pain and its impact on functioning in patients with chronic diseases (Cleeland and Ryan 1994). The short form version uses a 24-hour recall period (i.e., assesses pain and its impact over the previous 24 hours). The BPI uses a 0 (no pain) to 10 (pain as bad as you can imagine) numeric rating scale to measure how much pain has interfered with seven daily activities, including general activity, walking, work, mood, enjoyment of life, relations with others, and sleep. The BPI is completed at Baseline Week 0, Week 1, Week 2, and Week 4 (EOT)/ET.

12-Item Short Form Survey

The SF-12 survey, version 2 (SF-12v2), is a shortened form (12 items) of the SF-36 Health Survey (Ware et al. 1996). It is a self-reported general assessment of health-related quality of life from the subject's perspective. The SF-12 has eight domains including physical health summary measures: physical functioning, role-physical, bodily pain, and general health and mental health summary measures: vitality, social functioning, role-emotional, and mental health. From the evaluation of these domains, algorithms are used to generate physical and mental health composite summary scores, PCS and MCS, respectively, for comparison to normative data. In normative data, the mean score is set to 50; thus, scores >50 indicate beher physical or mental health than the mean scores and scores <50 indicate worse health. The timeframe for this scale is the past 4 weeks. The SF-12 is completed at Baseline (Week 0) and Week 4 (EOT)/ET.

Hospital Anxiety and Depression Scale

The HADS was developed to detect states of anxiety or depression (Zigmond and Snaith 1993). The questionnaire focuses on non-physical symptoms so that it can be used to diagnose depression in people with significant physical ill-health. The questionnaire comprises seven questions for anxiety and seven questions for depression, which are each scored separately. Each item on the questionnaire is scored from 0 (No, not at all) to 3 (Yes definitely), for a total score between 0 to 21 for either anxiety or depression. The timeframe for this scale is the past week.

The HADS is completed at Screening, Baseline (Week 0), and Week 4 (EOT)/ET.

Participant Scorecard

The Participant Score card presents subjects with data on key tasks reflecting their own performance in the study, plus automated and customized tips for how to improve their performance. Scores are assigned for study metrics that serve as markers of data quality and accurate symptom reporting, and have been shown to affect accuracy of study endpoints.

Scores are typically shown for medication adherence, eDiary compliance, and accuracy of symptom reporting, although other domains may be included. Although study staff are urged to be present with the subject during the scorecard review, no human intervention is required, which improves efficiency and timeliness of recommendations, while decreasing the biases and burdens introduced by filtering re-training through site staff. For-cause re-training on Accurate Symptom Reporting may be triggered on the platform in response to subject scores. The scorecard and as-needed re-training must be viewed by the subject prior to the completion of visit assessments, and reviewed by the Investigator during the subject's visit. The scorecard is viewed by the subject and reviewed by the Investigator at Visits 4, 5, and 6/EOT/ET.

Safety Assessments Physical Examination

A complete, general physical examination is conducted at Screening and a brief physical exam is conducted at Baseline (Week 0) and Week 4 (EOT)/ET. Height is measured and reported only at Screening and weight is measured and recorded at Screening, Baseline (Week 0), and Week 4 (EOT)/ET. The full examination should include a review of body systems and should include a neurological examination (e.g., level of consciousness, speech, cranial nerves [including pupil equality and reactivity], motor assessment, sensory assessment, coordination, gait, reflexes, and Romberg test). Height and weight are measured and reported as described above. The brief physical exam includes the following: evaluation of general appearance, respiratory, cardiovascular, and gastrointestinal systems. A general physical examination is conducted.

Vital Signs

Vital signs include body temperature, resting respiration rate, supine and standing systolic and diastolic blood pressure, and pulse rate. Blood pressure and pulse rate measurements will be taken after the subject rests for 5 minutes in the supine position. The subject will then be asked to stand and blood pressure and pulse rate will be taken after the subject stands for 1 minute and then again after 3 minutes. Subjects unable to stand may be assessed while sitting upright. A drop in SBP of >20 mmHg or in DBP of >10 mmHg or if the subject is experiencing lightheadedness or dizziness is considered abnormal and orthostasis should be considered.

Vital signs are evaluated at all designated study visits. A 15-minute window is permitted for vital sign measurements. Vital signs should be measured prior to (PK and laboratory) blood draws.

Electrocardiograms

All 12-lead electrocardiograms (ECGs) are complete, standardized recordings. A single 12-lead ECG is performed at Screening, at Baseline (Week 0) both predose and 1 hour postdose (the first dose of the day), Week 1, Week 2, and Week 4 (EOT)/ET. A 1-hour window is permitted for the predose ECG; a 20-minute window is permitted for the postdose ECGs. Electrocardiograms should be performed prior to blood sampling (or at least 30 minutes after blood sampling) and vital signs but after pain assessments are completed.

The subject must rest in a supine position for 5 minutes before the ECG is obtained. ECG tracings (paper or electronic) are reviewed and interpreted by a qualified clinician. All ECG tracings and results (ventricular rate, PR, QRS, QT, QTcF, and QTcB intervals) are included in the subject's record. At Screening, if the ECGs have a prolonged QTcF due to an identifiable cause, and it is medically appropriate to address that cause, a repeat ECG may be performed during Screening at the discretion of the Medical Monitor. At Baseline (Week 0), a subject may be enrolled based on the review and interpretation of the ECG by a qualified physician. If the interpretation of the ECG indicates a QTcF outside of the allowable range, the subject is discontinued from the study, but this is not be considered a protocol deviation. Columbia-Suicide Severity Rating Scale

The C-SSRS monitors changes in suicidal thinking and behavior over time, in order to determine risk (Posner et al. 2011). The following four constructs are measured: the severity of ideation, the intensity of ideation, behavior, and lethality. The Baseline/Screening version is administered at Screening, and the Since Last Visit version is administered at all subsequent visits. The C-SSRS results for each subject should be reviewed by the Investigator after completion. If at any time the C-SSRS results for a given subject reveal potential suicidality, then the Investigator should assess the clinical significance of such results. If a clinically significant risk of suicidality is identified for a subject, then the Investigator should discontinue the subject and implement appropriate treatment as described herein. C-SSRS is completed at all designated study visits.

Laboratory Evaluations

Clinical laboratory sample collection (including HbAlc at Screening only) is encouraged, but not required to be completed under fasting conditions. The laboratory evaluations include, but are not limited to, the following:

• Clinical chemistry serum tests (CHEM) o Sodium (Na), potassium (K), chloride (Cl), phosphorus (P), calcium

(Ca), carbon dioxide (C02), blood urea nitrogen (BUN), creatinine (CR), uric acid, o Estimated glomerular filtration rate (eGFR) should only be performed at Visit 1 (Screening) o Alanine aminotransferase (ALT), aspartate aminotransferase (AST), gamma- glutamyl transpeptidase (GGT), alkaline phosphatase (ALP), total bilirubin (TBIL), lactate dehydrogenase (LDH) o Creatine kinase (CK)/creatine phosphokinase (CPK) o Lipid panel should only be performed at Visit 1 (Screening):

• Total cholesterol, HDL-cholesterol, triglycerides, LDL-cholesterol, cholesterol/HDL ratio, non-HDL cholesterol; should only be performed at Visit 1 (Screening) o HbAlc should only be performed at Visit 1 (Screening) o Glucose o Albumin (ALB) should only be performed at Visit 1 (Screening) o Total protein should only be performed at Visit 1 (Screening) • Hematology tests o Complete blood count (CBC) including:

• White blood cell (WBC) count

• Complete differential (relative and absolute)

• Hematocrit (Hct), hemoglobin, red blood cells (RBC), platelets

• Reticulocyte count

• Endocrinology o Thyroid stimulating hormone (TSH) and free T4 (Screening)

• Pregnancy test o A serum pregnancy test should only be performed at screening (Table 4) for women of childbearing potential o A urine pregnancy test should be performed at Baseline (Week 0) and-Week 4 (EOT)/ET (Table 4) for women of child-bearing potential

• If urine cannot be obtained in women of childbearing potential, a serum pregnancy test should be done in its place

• COVID-19 test: o COVID-19 diagnostic PCR test at Screening

• Urinalysis (UA) o Blood, RBCs, WBCs, protein, glucose, ketones, specific gravity, pH, nitrates

• Urine drug screen (UDS) with reflex testing o A urine drug screen tests for controlled substances at Screening, Baseline Pain Assessment Period, and at Week 4/EOT/ET. A dipstick urine drug screen is performed at Baseline (Week 0) for rapid detection of controlled substances and for certain prescription medications in order to determine if the subject continues to meet subject eligibility. The following controlled substances are tested for with a urine-drug screen and/or urine dipstick according to the schedule presented in Table 4: amphetamine, barbiturates, benzodiazepines, buprenorphine, cocaine, ecstasy (MDMA), methadone, morphine/opiates, methamphetamine, marijuana (THC), phencyclidine (PCP), propoxyphene, tricyclic antidepressants. Negative drug screens are required for study eligibility.

• If there is a positive urine drug screen for an analgesic medication that is not allowed per protocol, the subject must washout of medication, if appropriate, prior to the Baseline Pain Assessment Period.

• If there is a positive urine drug screen for a medication that is allowed per protocol (e.g., metformin leading to a false positive for amphetamine), the subject must have a valid prescription for such medication, and if the subject denies use of the positive prohibited medication (e.g., amphetamine), they can be included in the study and it is not considered a protocol deviation

Laboratory evaluations are completed according to the schedule presented in Table 4 and procedures detailed in the study laboratory manual. Additional safety testing may be performed at the discretion of the Investigator or designee.

Table 4: Safety Laboratory Evaluations a COVID-19 diagnostic PCR test at Screening b Urine dipstick test are administered which must be negative for any non- permitted medications or drugs in order for the subject to continue in the study Abbreviations: CBC=complete blood count; CHEM=clinical chemistry serum tests; COVID- 19=coronavirus disease 2019; EOT=end of treatment; ET=early termination; UA=urinalysis

Electronic Clinical Outcome Assessments The electronic Clinical Outcome Assessment (eCOA) devices are used during the Baseline Pain Assessment Period and throughout the Double-blind study period. Subjects complete electronic-based assessments using handheld devices during the study. One device, an eDiary, is provided to all subjects to record pain scores, compliance with ingestion of study medication, and use of rescue medication. During the Baseline Pain Assessment Period, subjects rescue medication use. Compliance with recording of pain score and use of rescue medication is assessed for continued study eligibility. Subjects continue daily entry into the eDiary of pain scores use, and compliance with ingestion of study medication from Baseline (Week 0) through to Week 4 (EOT)/ET.

Pharmacokinetic Assessments

Pharmacokinetic blood samples are collected for measurement of plasma concentrations of Compound 1. Compound 1 plasma concentration data remain blinded until the unblinding of the clinical database at the end of the study.

At each predefined timepoint, PK samples are obtained for measurement of concentrations of Compound 1 at the following visits:

• Baseline (Week 0) visit and Visit 3; both before dosing and approximately 1 hour after dosing)

• Visit 4

• Visit 5

• Visit 6/or upon early termination (ET)

Pharmacokinetic blood samples taken at Visits 4, 5, and 6 should be collected at one of the following time intervals:

• 2-5 hours after morning dosing

• 6-9 hours after morning dosing

• 10-12 hours after morning dosing

Every effort should be made to collect PK samples at distinct time intervals during Visits 4, 5, and 6. However, if the interval is the same across these visits, then the collection time should vary within that interval. The following scenario is only for illustrative purposes, a number of other scenarios are possible.

• For example, if the time interval of 6-9 hours after morning dosing is used for Visits 4, 5, and 6, then every effort should be made to collect PK samples at 6, 7, and 8 hours after morning dosing at each of these visits, respectively.

When possible, an additional PK sample (approximately 4 mL sample) are collected from subjects who experience a serious adverse event (SAE) or an adverse event (AE) leading to discontinuation, as soon as possible after the occurrence of that event.

For all PK samples (scheduled and unscheduled), with the exception of those taken following an AE or SAE, the dates and times of administration of the last three doses of the study drug should be recorded. For samples collected from subjects who experience an SAE or an AE leading to discontinuation, the date and time of the last dose prior to the SAE or AE should also be recorded.

Blood Sampling

Five (5) approximately 4 mL venous blood samples are collected from each subject for measurement of plasma Compound 1 concentrations. In addition, a blood sample (approximately 4 mL sample) for determination of concentrations of Compound 1 are collected in the event of an SAE or an AE leading to discontinuation.

Specimen Preparation, Handling, Storage, and Shipment

Pharmacokinetic blood samples may be collected from a cannula port or via venipuncture. Pre-prepared PK sampling tubes are provided to each site within the lab visit kits for collection and storage of PK samples. At each timepoint, blood is collected, processed as appropriate, and samples are shipped to the central laboratory for storage and to the bioanalytical laboratory for analysis. For samples collected from subjects who experience any SAE or experience an AE leading to discontinuation, the date and time of the last dose of study drug prior to the SAE or AE leading to discontinuation are also recorded. A laboratory manual is provided for sample processing, storage, and shipping procedures.

Safety Follow-up

Safety will be further assessed during the follow-up period regardless of whether a subject completes the study or withdraws (or when they withdraw). The assessments to be conducted are outlined below and in Table 2.

Safety will be further assessed during a follow-up visit to occur in the clinic approximately 7 (±3) days after EOT/ET orocedures. During this in-clinic visit, pain intensity, adverse events (AEs), and concomitant medications, and AEs, since EOT. Then, a follow-up telephone call occurs approximately 30 (+4) days after the last dose of study drug to assess AEs and concomitant medications.

Unscheduled Visits Unscheduled visits may occur as determined by the Investigator. The following safety assessments generally should be recorded at each unscheduled visit: assessment of AEs, concomitant medications/treatments, C-SSRS, and measurement of vital signs. If an unscheduled visit is required for safety reasons, a 12-lead ECG and all appropriate clinical laboratory tests are also to be performed. The Investigator may perform any additional safety evaluations deemed by the Investigator to be clinically indicated.

ADVERSE EVENTS

An adverse event (AE) is defined as "any untoward medical occurrence in a patient or clinical study participant, temporally associated with the use of study drug, whether or not considered related to study drug". An AE can therefore be any unfavorable and unintended sign (e.g., an abnormal laboratory finding), symptom, or disease temporally associated with the use of a drug, without any judgment about causality or seriousness. An AE can arise from any use of the drug (e.g., off- label use, use in combination with another drug) and from any route of administration, formulation, or dose, including an overdose.

A suspected adverse reaction is any AE for which there is a reasonable possibility that the drug caused the AE.

AEs do not include the following:

• Stable or intermittent chronic conditions (such as myopia requiring eyeglasses) that are present prior to Baseline and do not worsen during the study

• Medical or surgical procedures (e.g., surgery, endoscopy, tooth extraction, transfusion). The condition that leads to the procedure is anAE if not present at time of consent, or scheduled surgery/procedure.

• Overdose of concomitant medication without any signs or symptoms is not considered an AE, but if subject is hospitalized or has other serious criteria, the overdose shall be reported on the Sponsor's Overdose Reporting form

• Hospitalization for elective surgery planned prior to study (situation where an untoward medical occurrence has not occurred)

• Pregnancy is not considered an AE, but if it occurs, it is reported on a pregnancy form

For subjects who discontinue from the study, AEs are recorded from the time informed consent is obtained until 30 (+4) days after the last dose of study drug. Definition of Serious Adverse Event

In addition to the severity rating, each AE is classified by the Investigator as "serious" or "not serious." The seriousness of an event is defined according to the applicable regulations and generally refers to the outcome of an event. An SAE is one that meets one or more of the following:

• Is fatal

• Is life threatening

• Results in disability or permanent damage

• Requires hospitalization (initial or prolonged)

• Results in congenital anomaly or birth defect

• Other serious event (medically significant/important medical event)

Definition of Life Threatening

A life threatening event places the subject at immediate risk of death from the event as it occurred. This does not include an AE, which, had it occurred in a more severe form, might have caused death.

Definition of Hospitalization

Hospitalization is defined by the Sponsor as a full admission to the hospital for diagnosis and treatment. This includes prolongation of an existing inpatient hospitalization. Examples of visits to a hospital facility that do not meet the serious criteria for hospitalization include:

• Emergency room visits (that do not result in a full hospital admission)

• Outpatient surgery

• Preplanned or elective procedures

• Protocol procedures

• Social hospitalization, defined as admission to the hospital as a result of inadequate family support or care at the subject's primary residence

Definition of Disability or Permanent Damage

Disability is defined as a persistent or significant incapacity or substantial disruption of the ability to conduct normal life functions.

Definition of Medically Significant

Important medical events (medically significant events) that may not result in death, be life threatening, or require hospitalization may be considered to be an SAE when, based upon appropriate medical judgment, they may jeopardize the subject or may require medical or surgical intervention to prevent one of the outcomes listed in this definition. Examples of such events are intensive treatment in an emergency room or at home for allergic bronchospasm, blood dyscrasias, or convulsions that do not result in hospitalization or development of drug dependency or drug abuse.

An SAE may also include any other event that the Investigator or Medical Monitor judges to be serious or that suggests a significant hazard, contraindication, side effect, or precaution.

Classification of an Adverse Event Severity of Event

The severity of each AE is assessed as described below and reported in detail as indicated on the eCRF:

• Mild: awareness of sign or symptom but easily tolerated, causing minimal discomfort, and not interfering with normal everyday activities

• Moderate: sufficiently discomforting to interfere with normal everyday activities

• Severe: incapacitating and/or preventing normal everyday activities

Relationship to Study Drug

The causality of each AE should be assessed and classified by the Investigator as "related" or "not related." An event is considered related if there is a reasonable possibility that the event may have been caused by the product under investigation (i.e., there are facts, evidence, or arguments to suggest possible causation).

The following factors should be considered when assessing causality:

• Temporal associations between the agent and the event

• Response to drug cessation (de-challenge) or re-challenge

• Compatibility with known class effect

• Known effects of concomitant medications

• Pre-existing risk factors

• A plausible mechanism

• Concurrent illnesses

• Past medical history Duration

The start and stop dates for AEs are recorded using the following criteria:

• Start: Date of the first episode of the AE or date of worsening in severity

• Stop: Date when AE ceased permanently, worsened in severity, or resolved with or without sequelae

Frequency

The frequency of the AE should be indicated according to the following definitions:

• Single: Experienced once, without recurrence at same severity

• Recurrent: More than one discrete episode with the same severity Action Taken with Study Drug

• Dose not changed: No change in study drug

• Drug interrupted: Study drug temporarily stopped

• Drug withdrawn: Study drug discontinued permanently

• Not applicable

• Unknown Therapy

• None: No new treatment instituted

• Medication: New treatment initiated as a direct result of AE

• Other: Other action required

Outcome

• Recovered/resolved: Recovered or resolved

• Recovered/resolved with sequelae: Recovered or resolved with sequelae

• Not recovered/not resolved: Not recovered or not resolved

• Fatal: Death due to an AE

• Unknown: Unknown

Seriousness

• Not serious

• Serious

Definition of Unexpectedness

An AE, the nature or severity of which is not consistent with the information provided in the Reference Safety Information section of the current Compound 1 Investigator's brochure.

Time Period and Frequency for Event Assessment and Follow-up

Adverse events are recorded from the time informed consent is obtained through the study safety follow-up period. If an AE is ongoing at the end of the study safety follow-up period, every reasonable attempt should be made to follow and appropriately treat the subject until the AE resolves or until the Investigator deems the AE to be chronic or stable.

In the event that a subject discontinues and has an ongoing AE at the time of discontinuation or is withdrawn from the study because of an AE, the subject should be followed and appropriately treated until the AE resolves or until the Investigator deems the AE to be chronic or stable.

Adverse Event Reporting

The Investigator must record all observed AEs and all reported AEs. At each visit, the Investigator should ask the subject a nonspecific question (e.g., "Have you noticed anything different since your last visit?") to assess whether any AEs have been experienced since the last report or visit. Note that any use of medication (and specifically any newly prescribed medication) during the course of a study may indicate the occurrence of an AE that may need to be recorded on both the AE and the concomitant medication page. All AEs, serious and not serious, are recorded on the AE eCRF page using appropriate medical terminology. Severity and relationship to study drug are assessed by the Investigator.

When possible, clinical AEs should be described by diagnosis and not by symptoms (e.g., "cold" or "seasonal allergies" instead of "runny nose"). All AEs, whether or not related to the study drug, must be fully and completely documented on the AE eCRF and in the subject's notes.

Serious Adverse Event Reporting

The reporting of SAEs by the Sponsor or designee to the regulatory authorities is a regulatory requirement. Each regulatory authority has established a timetable for reporting SAEs based upon established criteria. Serious AEs must be reported within 24 hours of discovery to the Sponsor or its designee; use the appropriate form for initial and/or follow-up reporting.

At a minimum, events identified by the Sponsor to require expedited reporting as serious, unexpected, and related to study drug must be brought to the attention of the responsible institutional review board/ethics committee (IRB/EC), as per applicable regulations. These are provided by the Sponsor after their assessment. For European Union member states, the Sponsor or its designee provides reports of suspected unexpected serious adverse reactions (SUSARs) directly to the ECs, as required by local legislation. In all other countries, it is the Investigator's responsibility to provide these expedited reports to the responsible IRB/EC. It is also the Investigator's responsibility to notify the responsible IRB/EC regarding any new and significant safety information.

When an SAE occurs, Investigators review all documentation related to the event and complete the paper SAE form with all required information (for initial and/or follow-up information) and fax or email (within 24 hours of discovery) to the contact information provided on the SAE form. Subjects are followed through the safety follow-up period (i.e., 30 [+4] days after last dose of study drug) for any SAEs and/or other reportable information until such events have resolved or the Investigator deems them to be chronic or stable.

In the event of any SAE (other than death), the study subject is instructed to contact the Investigator (or designee) using the telephone number provided in the ICF. All subjects experiencing an SAE are seen by the Investigator or designee as soon as is feasible following the report of the SAE. Serious AEs occurring after the safety follow-up period (i.e., 30 [+4] days after last dose of study drug) should be reported if in the judgment of the Investigator there is "a reasonable possibility" that the event may have been caused by the product. SAEs should also be reported to the IRB/EC according to local regulations.

Reporting of Pregnancy

Any female subject who becomes pregnant during the study (with or without AEs) must be withdrawn from the study and the pregnancy must be reported on the Pregnancy form within 24 hours of discovery to the Sponsor or its designee. Any female subject who becomes pregnant during the study are followed through the pregnancy outcome. If pregnancy occurs during the study, the pregnant subject should be unblinded so that counseling may be offered based on whether the fetus was exposed to the active drug or placebo.

Any AEs that are the consequence of pregnancy and which meet the criteria for serious should also be reported via the SAE form.

Reporting Paternal Drug Exposure

Paternal drug exposure is defined as a father's exposure to a medicinal product before or during his partner's pregnancy. Any paternal drug exposure cases must be reported to the Sponsor within 24 hours of discovery via the Pregnancy form. Any AEs that are the consequence of paternal drug exposure and which meet the criteria for serious must also be reported to the Sponsor within 24 hours of discovery via the SAE form.

Reporting of Overdose

An overdose is a deliberate or inadvertent administration of a treatment (i.e., study drug or rescue medication) at a dose higher than the maximum recommended dose per protocol. It must be reported to the Sponsor or designee on the Sponsor Overdose Reporting form within 24 hours of discovery. In addition, all events of overdose are to be captured as protocol deviations. CLINICAL MONITORING

Clinical site monitoring is conducted to ensure that the rights and well-being of human subjects are protected, that the reported study data are accurate, complete, and verifiable, and that the conduct of the study is in compliance with the currently approved protocol and amendment(s) as applicable, with GCP, and with applicable regulatory requirements. Details of the study site monitoring process are described in a separate clinical monitoring plan document.

STATISTICAL METHODS AND DATA ANALYSIS

Statistical methods are documented in detail in a statistical analysis plan (SAP) to be approved by the Sponsor prior to database lock. Deviations from the approved SAP are described and justified in the final clinical study report.

Statistical Hypotheses

Let Ai ( //id , - JUPBO) be the difference in the mean change from Baseline to Week 4 in the weekly average of the daily average pain between each of the Compound 1 (jiAct ) dose groups and placebo ( mRBO ) group. The null hypothesis is: \, 0; the alternative hypothesis is: A¹ 0; i= 1, 2.

Sample Size Determination

Approximately 240 subjects are randomized in a 1 : 1 : 1 ratio to Compound 1 800 mg BID dose, Compound 1 400 mg QID dose, or placebo. Assuming a treatment difference of 0.85 and a common standard deviation of 1.7 between an Compound 1 dose arm and placebo, 64 subjects per arm is needed to provide approximately 80% power to detect this treatment difference using a 2 sample t-test at 2-sided alpha level of 0.05. Assuming a discontinuation rate of 20%, 80 subjects per treatment group are randomized.

Subject Populations for Analysis

The Safety Analysis Set includes all randomized subjects who received at least one dose of study drug (Compound 1 or placebo). Subjects are analyzed based on the treatment that they actually received. The Safety Analysis Set is used for all safety analyses. The Full Analysis Set (FAS) includes all randomized subjects who received at least one dose of study drug and with baseline pain assessments and at least one post-baseline pain assessment. Subjects are analyzed based on the treatment to which they are assigned. The Full Analysis Set is used for the analysis of all efficacy endpoints. For Compound 1 plasma concentration summaries, the Pharmacokinetics Analysis Set consists of subjects with at least one measurable Compound 1 plasma concentration.

Statistical Analyses

For continuous variables, descriptive statistics includes the following information: the number of subjects with data values (n), mean, standard error of the mean, median, standard deviation, minimum, and maximum. For categorical or ordinal data, frequencies and percentages are displayed for each category. All statistical hypotheses are tested at the 0.05 significance level. Demographic and baseline characteristics, including medical history and exposure to study drug are summarized descriptively by treatment group and by all subjects combined.

Primary Analyses

The primary efficacy variable is analyzed using an analysis of covariance model (ANCOVA) based on the FAS with treatment, sex, and baseline K-L score (randomization strata) as factors and baseline weekly average of daily average pain score as a covariate in the model. The primary comparison is between each Compound 1 dose group versus the placebo group. The comparison between the average of the means of the two Compound 1 dose groups versus the mean of placebo group is also conducted. Missing data are imputed using multiple imputation based on missing at random assumption (MAR) with an exception of missing data from subjects who are treated with Compound 1 and discontinue the study due to lack of efficacy or adverse events. Their missing data are imputed using the data from placebo group. The details of missing data imputation and multiplicity adjustment are described in the SAP.

Sensitivity analysis using pattern mixture model and tipping point approach with multiple imputation to impute missing data is performed to assess the robustness of the results due to treatment discontinuation and other intercurrent events.

Secondary Analyses

For analysis of continuous secondary endpoints, the analysis method is the same as that used for the primary variables except for PGIC which are analyzed using analysis of variance (ANOVA) with treatment, sex, and baseline K-L score as factors. For analysis of categorical variables in secondary endpoints, e.g., proportions of subjects with >30% reduction from baseline to Week 4 in the weekly average of the daily average NRS score; the Cochran Mantel Haenszel approach stratified by the randomization strata are used for subjects with missing data considered as non-responders.

Exploratory Analyses Safety Analyses

Safety data are summarized by treatment group using descriptive statistics. No formal statistical testing is performed for any of the safety endpoints. Adverse events are classified into standard terminology using the Medical Dictionary for Regulatory Activities (MedDRA). Treatment-emergent adverse events (TEAEs), TEAEs leading to discontinuation, TEAEs related to study drug, TEAEs by maximum severity, fatal TEAEs, SAEs, SAEs related to study drug, and TEAEs of special interest (AESI) are all summarized.

Descriptive statistics for ECGs, vital signs and weight, and clinical laboratory parameters, including changes from Baseline (prior to first dose), are tabulated by timepoint and by treatment group. The incidence of subjects with prolonged QTc intervals and changes in QTc intervals in accordance with ICH guidelines is also summarized by treatment group.

Additional safety analysis details are specified in the SAP.

Pharmacokinetic Analyses

Plasma concentration data for Compound 1 are listed and summarized using descriptive statistics. Results are used for other analyses (e.g., population PK modelling), which are presented in a separate report.

Pharmacokinetic/Pharmacodynamic Analyses

Guided by exploratory analyses, PK/PD models to describe the exposure-response relationship between Compound 1 exposure parameters and the relevant efficacy and safety endpoints are developed using appropriate PK/PD methods. Results are presented in a separate report per a prespecified data analysis plan.

Measures to Minimize Bias

At Baseline (Week 0), eligible subjects who meet inclusion and do not meet exclusion criteria aree randomized in a 1:1:1 ratio to receive Compound 1 800 mg BID, Compound 1 400 mg QID, or placebo, according to a randomization schedule. Treatment assignments are blinded to all study subjects, Investigators, site personnel (with the exception of the unblinded pharmacist and verifier), and Sponsor personnel.

In order to maintain the double-blind design of the study, all subjects receive the same numbers of tablets at the same intervals, regardless of the treatment group to which they are randomized. Placebo tablets are size- and color-matched to the Compound 1 tablets.

Masking Procedures

This unmasked protocol version provides details of certain study design elements, procedures, and statistical methods that are not available in the masked version of the protocol. This document is intended for use only by the unmasked Sponsor and restricted clinical service providers and their designated agents for purposes of regulatory document preparation in conjunction with review by IRBs, IECs, and regulatory authorities.

Access to this document by other entities may be considered on a case-by-case basis by the Sponsor. The information contained herein is UNMASKED and CONFIDENTIAL. Therefore, it must NOT be shared with or communicated to any individual at an investigational site or from site facing members of the clinical operations team of the contract research organization except with explicit and fully documented authorization from the Sponsor. The key elements revealed herein but that are masked in the masked protocol are the Compound 1 dosing regimens and inclusion criteria specific to the Baseline Pain Assessment Period. Investigators receive the masked version of the clinical study protocol.

Breaking the Study Blind/Subject Code

For the final analysis, the treatment codes for all subjects are released to the Sponsor after all subjects have completed the study and the clinical database is locked.

In case of an emergency, the investigator has the sole responsibility for determining if unblinding of a participants' intervention assignment is warranted. Participant safety must always be the first consideration in making such a determination. If the investigator decides that unwinding is warranted, the investigator shoWd make every effort to contact the Sponsor prior to unwinding a participant's intervention assignment unless this coWd delay emergency treatment of the participant. If a participant's intervention assignment is unblinded, the sponsor must be notified within 24 hours after breaking the blind.

If pregnancy occurs during the study, the pregnant subject should be withdrawn and unblinded so that counseling may be offered based on whether the fetus was exposed to the active drug or placebo.

STUDY MANAGEMENT AND DATA COLLECTION Data Collection and Management Responsibilities

All documents required for the conduct of the study as specified in the ICH GCP guidelines are maintained by the Investigator in an orderly manner and made available for monitoring and/or auditing by the Sponsor and regulatory authorities.

The Investigator and institution must permit authorized representatives of the Sponsor or designees (including monitors and auditors), regulatory authorities (including inspectors), and the IRB/EC direct (or remote) access to source documents (such as original medical records) as allowed by local regulations. Direct (or remote) access includes permission to examine, analyze, verify, and reproduce any records and reports that are needed for the evaluation of the study, either in person or through a remote video/electronic medium, if applicable. The Investigator must ensure the reliability and availability of source documents from which the information on the eCRF was derived.

Source Documents

All study specific information obtained at each study visit must be recorded in the subject's record (source documentation), and then entered into a validated electronic data capture (EDC) database by trained site personnel. The source documentation may consist of source notes captured by site personnel as well as laboratory reports, ECG reports, and electronic source data.

Case Report Forms

Subject data required by this protocol are to be recorded in an EDC system on eCRFs. The Investigator and his or her site personnel is responsible for completing the eCRFs. The Investigator is responsible for the accuracy and reliability of all the information recorded on the eCRFs. All information requested on the eCRFs needs to be supplied, including subject identification data, visit date(s), assessment values, etc., and any omission or discrepancy requires explanation. All information on eCRFs must be traceable to source documentation (unless eCRF is considered the source) at the site.

Confidentiality

The Investigator must ensure that each subject's anonymity is maintained as described below. On the eCRFs, medical records, or other documents submitted to the Sponsor or designees, subjects must be identified by a subject identification number only. Subject identifiers uniquely identify subjects within the study and do not identify any person specifically. Documents that are not for submission to the Sponsor or designees (e.g., signed ICFs) should be kept in strict confidence by the Investigator in compliance with Federal regulations or other applicable laws or ICH guidance on GCP. Data collection and handling should comply with the European Union General Data Protection Regulation (EU GDPR), where applicable. Acadia has assigned a Data Protection Officer (DPO) as per the EU GDPR. Study Records Retention

Investigators are required to maintain all essential study documentation as per ICH GCP guidelines. This includes, but is not limited to, copies of signed, dated and completed eCRFs, documentation of eCRF corrections, signed ICFs, audio recordings, subject-related source documentation, and adequate records for the receipt and disposition of all study drug. Investigators should maintain all essential study documentation, for a period of at least 2 years following the last approval of marketing application in an ICH region (US, Europe, and Japan), or until at least 2 years after the drug investigational program is discontinued, unless a longer period is required by applicable law or regulation. Only the Sponsor can notify an Investigator or vendor when any records may be discarded. Investigators should contact the Sponsor before destroying any files.

Protocol Exceptions and Deviations

No prospective entry criteria protocol deviations are allowed; all subjects must meet all eligibility criteria in order to participate in the study. Protocol waivers for eligibility are not granted by the Sponsor under any circumstances. If, during the course of a subject's post enrollment participation in the trial it is discovered that the subject did not meet all eligibility criteria, this is reported as a major protocol deviation and not a waiver. In this situation, the subject is discontinued, unless the discontinuation presents an unacceptable medical risk. The justification to allow the subject to continue in the trial is made by the Sponsor, with medical input from the Investigator, and is documented. All follow-up safety assessments must be completed and documented as outlined in the protocol. The Investigator must report any protocol deviation to the Sponsor and, if required, to the IRB/EC in accordance with local regulations, within reasonable time.

Protocol Amendments

Changes to the protocol may be made only by the Sponsor (with or without consultation with the Investigator). All protocol modifications must be submitted to the site IRB/EC in accordance with local requirements and, if required, to regulatory authorities, as either an amendment or a notification. Approval for amendments must be awaited before any changes can be implemented, except for changes necessary to eliminate an immediate hazard to trial subjects, or when the changes involve only logistical or administrative aspects of the trial. No approval is required for notifications.

QUALITY MANAGEMENT Risk Management

The Sponsor utilizes the ICH E6 (GCP) Revision 2 risk management approach that includes methods to assure and control the quality of the trial proportionate to the risks inherent in the trial and the importance of the information collected. The intent is that all aspects of this trial are operationally feasible and that any unnecessary complexity, procedures, and data collection are avoided. The Sponsor's risk management approach includes the following documented activities: o Critical Process and Data Identification: during protocol development, risks of processes and data that are critical to ensure human subject protection and the reliability of trial results are identified and assessed o Risk Identification: risks to critical trial processes, governing systems, investigational product, trial design, data collection, and recording are identified o Risk Evaluation: identified risks are evaluated by considering the following factors:

(a) likelihood of occurrence, (b) impact on human subject protection and data integrity, and (c) detectability of errors. o Risk Control: risks that can be avoided, reduced (i.e., mitigated), or accepted are differentiated. Risk mitigation activities are incorporated in protocol design and implementation, study plans, training, processes, and other documents governing the oversight and execution of study activities. Where possible, predefined quality tolerance limits are defined to identify systematic issues that can impact subjectsafety or data integrity and deviations from the predefined quality tolerance limits trigger an evaluation and possibly an action. Contingency plans are developed for issues with a high risk factor that cannot be avoided. o Periodic risk review, communication, and escalation of risk management activities during trial execution and risk outcome reporting in the clinical study report (CSR). Quality Control and Quality Assurance

The Sponsor or designees and regulatory authority inspectors are responsible for contacting and visiting the Investigator for the purpose of inspecting the facilities and, upon request, inspecting the various records of the trial (e.g., eCRFs and other pertinent data) provided that subject confidentiality is respected.

The Sponsor's or designee's monitor is responsible for inspecting the eCRFs at regular intervals throughout the study to verify adherence to the protocol; completeness, accuracy, and consistency of the data; and adherence to local regulations on the conduct of clinical research. The monitor should have access to subject medical records and other study -related records needed to verify the entries on the eCRFs. The monitor may review documents remotely, as needed, in conjunction with site policies and procedures. The Investigator agrees to cooperate with the monitor to ensure that any problems detected in the course of these monitoring visits are resolved.

In accordance with ICH guidance on GCP and the Sponsor's audit plans, sites participating in this study may be audited. These audits may include a review of site facilities (e.g., pharmacy, drug storage areas, and laboratories) and review of study-related records may occur in order to evaluate the trial conduct and compliance with the protocol, ICH guidance on GCP, and applicable regulatory requirements. The Sponsor's or designee's representatives, regulatory authority inspectors and IRB/EC representatives who obtain direct (or remote) access to source documents should also respect subject confidentiality, taking all reasonable precautions in accordance with applicable regulatory requirements to maintain the confidentiality of subjects' identities.

ETHICAL CONSIDERATIONS Ethical Standard

The study is conducted in compliance with the protocol, the Declaration of Helsinki, ICH GCP, and other applicable regulatory requirements (e.g., Serious Breach reporting, urgent safety measures, and European Union General Data Protection Regulation [EU GDPR]). The study is performed in accordance with current US Health Insurance Portability and Accountability Act (HIPAA) regulations, US FDA GCP Regulations (US CFR 21 parts 50, 54, 56, and 312), and ICH guidance on GCP (E6) and clinical safety data management (E2A).

In accordance with Directive 75/318/EEC, as amended by Directive 91/507/EEC, the final clinical study report is signed by an Investigator and/or Coordinating Investigator who is designated prior to the writing of the clinical study report.

Institutional Review Board/Ethics Committee

The Investigator or designee provides the IRB/EC with all requisite material, including a copy of the protocol, informed consent, any subject information or advertising materials, and any other requested information. The study is not initiated until the IRB/EC provides written approval of the protocol and the informed consent and until approved documents have been obtained by the Investigator and copies received by the Sponsor. All amendments are sent to the IRB/EC for information (minor amendment) or for submission (major amendment) before implementation. The Investigator supplies the IRB/EC and the Sponsor with appropriate reports on the progress of this study, including any necessary safety updates, in accordance with the applicable government regulations and in agreement with policy established by the Sponsor.

Informed Consent Process

Properly executed, written informed consent must be obtained from each subject prior to any screening procedures. The informed consent must, at a minimum, include the elements of consent described in the ICH guidance on GCP and the US CFR 21 part 50.25. A copy of the ICF planned for use is reviewed by the Sponsor or designee for acceptability and must be submitted by the Investigator or designee together with the protocol, to the appropriate IRB/EC for review and approval prior to the start of the study at that investigational site. Consent forms must be in a language fully comprehensible to the prospective subject. The Investigator must provide the

Sponsor or designee with a copy of the IRB/EC letter approving the protocol and the ICF before the study drug supplies is shipped and the study can be initiated. The consent form must be revised if new information becomes available during the study that may be relevant to the subject's willingness to continue participation. Any revision must be submitted to the appropriate IRB/EC for review and approval in advance of use.

Consent and Other Informational Documents Provided to Subjects

The subject must be given a copy of the signed informed consent and the original maintained in the designated location at the site.

Consent Procedures and Documentation

It is the Investigator or designee's responsibility to obtain written informed consent from the subject after adequate explanation of the aims, methods, anticipated benefits, and potential hazards of the study. The subject must be given ample time to decide about study participation and opportunity to inquire about details of the study. The IRB/EC -approved consent form must be personally signed and dated by the subject and by the person who conducted the informed- consent discussion. The Investigator or appropriate site personnel must document the details of obtaining informed consent in the subject's study documents.

The subject must also indicate his/her understanding of the study. The subject must provide written agreement prior to any screening visit procedures being performed indicating his/her agreement to participate in the study.

Records related to a study subject's participation are maintained and processed according to local laws, and where applicable, the European Union General Data Protection Regulation (EU GDPR). The consent and study information documentation include statements describing local and regional requirements concerning data privacy, and who to contact for questions.

Enumerated Embodiments

The following exemplary embodiments are provided, the numbering of which is not to be construed as designating levels of importance: Embodiment 1 provides a method of treating, ameliorating, and/or preventing osteoarthritic pain in a subject, the method comprising: administering to the subject having osteoarthritic pain a therapeutically effective amount of a composition comprising a compound of Formula I and at least one pharmaceutically acceptable excipient or carrier: Formula I (Compound 1).

Embodiment 2 provides the method of embodiment 1, wherein the composition comprises from about 200 mg to about 1600 mg of Compound 1.

Embodiment 3 provides the method of any one of embodiments 1-2, wherein the composition comprises from about 200 mg to about 800 mg of Compound 1.

Embodiment 4 provides the method of any one of embodiments 1-3, wherein the composition comprises about 400 mg to about 800 mg of Compound 1.

Embodiment 5 provides the method of any one of embodiments 1-4, wherein administration of the composition results in a maximum observed plasma concentration (Cmax) of about 5 pg/mL to about 300 pg/mL of Compound 1 in the subject.

Embodiment 6 provides the method of any one of embodiments 1-5, wherein administration of the composition results in an area under the curve (AUCINF) of about 100 hrpg/mL to about 3000 hrpg/mL of Compound 1 in the subject.

Embodiment 7 provides the method of any one of embodiments 1-6, wherein the subject is human.

Embodiment 8 provides the method of any one of embodiments 1-7, wherein the composition comprises at least one additional pharmaceutically active agent.

Embodiment 9 provides the method of any one of embodiments 1-8, wherein the composition comprises at least one pharmaceutically acceptable carrier.

Embodiment 10 provides the method of any one of embodiments 1-9, wherein the composition is an oral composition.

Embodiment 11 provides the method of any one of embodiment 10, wherein the oral composition is in a form comprising a tablet, hard capsule, soft capsule, cachet, troche, or lozenge.

Embodiment 12 provides the method any one of embodiments 10-11, wherein the oral composition is in a unit dose form. Embodiment 13 provides the method of any one of embodiments 1-12, wherein the composition is administered once, twice, three, or four times per day to the subject.

Embodiment 14 provides the method of any one of embodiments 1-13, wherein the composition is administered twice or four times per day to the subject.

Embodiment 15 provides the method of any one of embodiments 1-14, wherein the osteoarthritic pain is in or near at least one joint in the subject.

Embodiment 16 provides the method of embodiment 15, wherein the joint is at least one of a fixed joint, a cartilaginous joint, or a synovial joint.

Embodiment 17 provides the method of any one of embodiments 15-16, wherein the joint is at least one of a suture, vertebral, knee, shoulder, hip, elbow, finger, jaw, trochoid, plane, or saddle joint.

Embodiment 18 provides the method of any one of embodiments 15-17, wherein the joint is a knee joint.

Embodiment 19 provides the method of any one of embodiments 1-18, wherein the osteoarthritic pain is chronic osteoarthritic pain.

Embodiment 20 provides a method of treating or ameliorating osteoarthritic pain or symptoms of osteoarthritis in a subject, the method comprising administering to a subject suffering from osteoarthritic pain or symptoms of osteoarthritis a unit dose of a composition comprising about 400 to about 1600 mg of a compound of Formula I and at least one pharmaceutically acceptable excipient or carrier:

^• HC! Formula I (Compound 1), wherein the composition is administered once, twice, thrice, or four times per day to the subject and wherein the total daily dose of Compound 1 does not exceed 1600 mg.

Embodiment 21 provides the method of embodiment 20, wherein the composition comprises 400 mg of Compound 1 and is administered four times daily to the subject.

Embodiment 22 provides the method of embodiment 20, wherein the composition comprises 800 mg of Compound 1 and is administered twice daily to the subject.