CROSS REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of priority to U.S. Provisional Patent Application No. 62/788,093, filed on January 3, 2019, entitled“Nasal Drug Delivery Device” which is incorporated herein by reference in its entirety for all purposes.

BACKGROUND

[0002] This disclosure relates generally to a drug delivery device, and specifically to a nasal drug delivery device for delivering drugs to an upper nasal cavity of a user.

[0003] The central nervous system (CNS) includes the brain, the brain stem, and the spinal cord. The CNS is isolated from the external world by several membranes that both cushion and protect the brain, the brain stem, and the spinal cord. For example, the membranes that form the blood-brain barrier (BBB) protect the brain from certain contents of the blood. The blood- cerebrospinal fluid barrier (BCSFB) protects other portions of the CNS from many chemicals and microbes.

[0004] Traditional methods for delivering compounds to the CNS are typically invasive. For example, a pump implanted in the skull, such as an intracerebroventricular pump, can deliver a variety of compounds to the brain. However, implanting such a pump requires brain surgery, which can entail a variety of serious complications. Certain compounds, for example epidural painkillers, can be injected directly through the protective membrane into the CNS. However, such injection is impractical for most compounds.

[0005] Intranasal administration has traditionally focused on the distribution of drug solutions as a mist for topical delivery to the nasal epithelium. Because of the nasal cavity's easily accessed vascular bed, nasal administration of medications has focused the delivery of medications either locally to the nasal cavity or directly to the blood stream.

[0006] Much of the current brain research is focused on the enhancement of the drug being delivered to the brain by various formulations. The traditional approaches to improve uptake of compounds to the brain by formulation enhancement include (1) mucoadhesive formulations; 2) penetration enhancers; 3) liposomes; 4) vasoconstrictors; and 5) nanoparticles. Examples of various compounds with have enhanced formulations include various cytokines, for example, tumor necrosis factors, interleukins, and interferons discussed in U.S. Pat. No. 6,991,785 and growth and differentiation factor-5 (GDF-5) and related proteins discussed in US Publication No. 20100074959.

[0007] Targeting of drugs to the central nervous system (CNS) is a challenging task. A great number of drugs, including biotechnology products, are candidates for treatment of CNS diseases, but drug delivery is a problem for brain targeting. A limitation in the treatment of brain tumors is that less than 1% of most therapeutic agents administered systemically are able to cross the BBB. The transport of small molecules across the BBB is the exception rather than the rule, and 98% of all small molecules do not cross the BBB (Pardride, NeuroRx. 2005 January; 2(1): 1- 2. 2005); approximately 100% of large-molecule drugs or genes do not cross the BBB (Pardride, NeuroRx. 2005 January; 2(1): 1-2. 2005). The BBB allows small (about less than 500 Da), lipophilic molecules from the bloodstream to enter the CNS (Pardridge, Arch Neurol. 2002; 59:35-40). Many larger therapeutic agents are prevented from reaching the brain for treating CNS disorders such as but not limited to Parkinson's disease, Alzheimer's disease, depression, stroke, and epilepsy (Pardridge, NeuroRx. 2005 January; 2(1): 3-14). Disorders including autism, lysosomal storage disorders, fragile X syndrome, ataxis, and blindness, are serious disorders where there is little effective treatment. In many of these cases, the gene underlying the disease is known, but BBB delivery is the rate-limiting problem in gene therapy or enzyme replacement therapy, and no therapeutics have been developed. Drug delivery of therapeutic compounds, for example proteins, faces several challenges because of their instability, high enzymatic

metabolism, low gastrointestinal absorption, rapid renal elimination, and potential

immunogenicity .

[0008] There is a need for devices that can deliver compounds to the upper nasal cavity for direct nose-to-brain delivery. Certain existing nasal drug delivery devices do not adequately propel the drug from the device. Inconsistent propulsion of drug due to inconsistent user actuation is also far from optimal. For example, some existing devices are manually actuated and may be used in conjunction with a manual pump, such that the actuation of the device is dependent on a user’s rate and/or strength of actuation of the pump. Some existing devices require the user to coordinate their breathing with device actuation, which can produce variable results due to differences in a user’s breath power. In addition, some drug products are in an encapsulated form, which requires the capsule to be opened or punctured to administer the drug, which may result in particulate matter from the capsule contaminating the drug. Even further, in a metered dose inhaler (MDI) type device, some drug products do not readily mix and/or stay suspended with propellants.

[0009] Better mechanisms for administering desired agents to the brain, brain stem, and/or spinal cord are needed.

SUMMARY

[0010] A device for delivering a compound to the upper nasal cavity is described. In one embodiment, the device includes a housing body comprising an actuator, a stem, and a release button. The actuator is configured to move relative to the housing body, where actuation of the actuator is configured to actuate a canister thereby releasing a contained propellant. The stem protrudes from the housing body and comprises a mating interface that mates with a nozzle containing the compound. The release button is positioned within the housing body and moves relative to the housing body. The release button is directly connected to a securing mechanism that couples the nozzle to the mating interface, where actuation of the release button decouples the nozzle from the mating interface.

[0011] In one embodiment, the nozzle comprises a nozzle body, a diffuser, an outlet orifice, a removable seal, and a receiving cavity. The nozzle body comprises a channel that extends between a proximal end and a distal end of the nozzle body, and the diffuser is positioned within the channel. The outlet orifice is disposed at a distal end of the channel, and the removable seal is positioned across the outlet orifice. The compound is contained within the channel between the diffuser and the removable seal, and the removable seal may be removed by a user before the compound is administered. The receiving cavity is disposed about an outer surface of the nozzle body and receives a reciprocal mating interface of the device.

[0012] Upon user actuation of the device, the released propellant travels to the channel of the nozzle body, contacts the diffuser, and propels the compound out the outlet orifice for delivery into the upper nasal cavity. In this configuration, the device administers the dose to the upper nasal cavity independent of the user’s breathing and/or user’s rate and/or strength of actuation. In addition, the nozzle may be coupled to and decoupled from the housing body. The nozzle is used to deliver a single dose of the compound, such that after dispensing the dose, the nozzle may be removed from the housing body and a new nozzle may be attached for delivering a future dose. This configuration maintains the integrity of the compound contained within the detachable nozzle and consistently administers the dose to the upper nasal cavity.

BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure (FIG.) 1A illustrates a perspective view of a nasal drug delivery device, in accordance with one or more embodiments.

[0014] FIG. IB illustrates a side view of the device of FIG. 1 A with a nozzle detached, in accordance with one or more embodiments.

[0015] FIG. 2 illustrates a cross-sectional view of the device of FIGS. 1A and IB, in accordance with one or more embodiments.

[0016] FIGS. 3 A and 3B illustrate a side view and a cross-sectional view, respectively, of an internal assembly housed within the device of FIGS. 1A and IB, in accordance with one or more embodiments.

[0017] FIGS. 4A and 4B illustrate an exploded view and a cross-sectional view, respectively, of a nozzle, in accordance with one or more embodiments.

[0018] FIGS. 5 A and 5B illustrate an exploded view and a cross-sectional view, respectively, of a nozzle, in accordance with one or more embodiments.

[0019] FIGS. 6A and 6B illustrate an exploded view of the internal assembly and the internal assembly seated within a housing body, respectively, in accordance with one or more

embodiments. [0020] FIGS. 7A-7C illustrate an internal surface of the housing of the device of FIGS. 1A and IB and a release button, in accordance with one or more embodiments.

[0021] FIG. 8 a perspective, partially exploded view of the device of FIGS. 1A and IB, in accordance with one or more embodiments.

[0022] The figures depict embodiments of the present disclosure for purposes of illustration only. One skilled in the art will readily recognize from the following description that alternative embodiments of the structures and methods illustrated herein may be employed without departing from the principles, or benefits touted, of the disclosure described herein.

DETAILED DESCRIPTION

[0023] Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art pertinent to the methods and compositions described. As used herein, the following terms and phrases have the meanings ascribed to them unless specified otherwise:

[0024] As used herein the specification,“a” or“an” may mean one or more.

[0025] A“diagnostic agent” refers to and encompasses an atom, molecule, or compound that is useful in diagnosing a disease. Diagnostic agents include, but are not limited to, radioisotopes, dyes, contrast agents, fluorescent compounds or molecules and enhancing agents (e.g., paramagnetic ions). A non-radioactive diagnostic agent is a contrast agent suitable for magnetic resonance imaging, computed tomography, or ultrasound. The diagnostic agent can be used to perform positron emission tomography (PET), MRI, X-ray, CT, ultrasound, operative, intravascular, laparoscopic, or endoscopic procedure.

[0026] A“diffuser” refers to and encompasses a component for dispersing or deflecting a compound in various directions.

[0027] A“frit” is one type of a diffuser and shall refer to and encompass a porous member or filter.

[0028] An“imaging agent” refers to and encompasses an atom, molecule or compound that is useful in detecting physical changes or produces images of internal body tissues. In some aspects, the imaging agent may be a diagnostic agent. [0029] A“propellant” shall refer to and encompass a compound that acts as a vehicle for creating propulsion or thrust.

[0030] The term“therapeutically effective amount” refers to and encompasses an amount of a drug effective to treat a disease or disorder in a mammal. In one aspect, the therapeutically effective amount refers to a target CNS concentration that has been shown to be effective in, for example, slowing disease progression. Efficacy can be measured in conventional ways, depending on the condition to be treated.

[0031] The term“treatment” and“treat”, and the like, refers to and encompasses therapeutic or suppressive measures for a disease or disorder leading to any clinically desirable or beneficial effect, including, but not limited to, alleviation or relief of one or more symptoms, regression, slowing or cessation of progression of the disease or disorder. Treatment can be evidenced as a decrease in the severity of a symptom, the number of symptoms, or frequency of relapse.

[0032] A“user” or“subject” shall refer to and encompass a human or other animal. For example, the animal may be a primate or a non-primate and may include a rabbit, bovine, equine, pig, rat, mouse, dog or cat.

[0033] The device may be used in treatment, prevention, palliative care for humans and veterinary purposes. The device may be used in research and industrial uses. For example, the device may be used to deposit compound in agricultural settings.

[0034] When trade names are used herein, applicants intend to independently include the trade name product formulation, the generic drug, and the active pharmaceutical ingredient(s) of the trade name product.

[0035] For clarity of disclosure, and not by way of limitation, the detailed description of the invention is divided into the subsections which follow.

[0036] Intranasal administration of compounds to the upper nasal cavity offers several advantages over traditional surgical, intravenous or oral routes for administration across the blood brain barrier (BBB). The upper nasal cavity may include the olfactory region and the middle and superior turbinate regions, among other regions within the nasal cavity. Intranasal administration to specifically the olfactory region avoids gastrointestinal destruction and hepatic first pass metabolism, such as destruction of drugs by liver enzymes, allowing more drug to be cost-effectively, rapidly, and predictably bioavailable than if it were administered orally.

Intranasal administration provides ease, convenience and safety. Intranasal drug administration is generally painless (taking into consideration that pain may be a subjective measurement which varies by patient) and does not require sterile technique, intravenous catheters or other invasive devices, and is generally immediately and readily available for all patients. Intranasal administration can rapidly achieve therapeutic brain and spinal cord drug concentrations.

[0037] Nasally administered compounds contact the upper olfactory region and molecular transport occurs directly across this tissue and into compartments of the central nervous system. (Henry, R. J., et al., Pediatr Dent, 1998. 20(5): p. 321-6; Sakane, T., et al., J Pharm Pharmacol, 1991. 43(6): p. 449-51; Banks, W. A., et al., J Pharmacol Exp Ther, 2004. 309(2): p. 469-75; Westin, et al., Pharm Res, 2006. 23(3): p. 565-72). The olfactory mucosa is located in the upper nasal cavity, just below the cribriform plate of the skull. It contains olfactory cells which traverse the cribriform plate and extend up into the cranial cavity. When compounds come in contact with this specialized mucosa, they are rapidly transported directly into the brain, they bypass the BBB, and are rapidly transported directly into the central nervous system, often faster than if the compound is given intravenously.

[0038] The olfactory mucosa includes the olfactory epithelium. The olfactory epithelium is located at the top of the nose between the superior turbinate and the roof of the nasal cavity, just beneath the cribriform plate of the ethmoid bone. In humans, it covers about 10 to about 20 cm ² , or about 8% of the total nasal surface area, and is composed of four main cell types: epithelial cells, olfactory receptor neurons, supporting cells, and basal cells. (Mathison S. et al., (1998) Journal of Drug Targeting 5: 415-441). Although 3% of the nasal cavity is occupied by olfactory epithelium (Morrison and Costanzo, 1990), this route is direct, since the olfactory neurons do not have a synapse between the receptive element and the afferent path (Ding and Dahl, 2003). The olfactory epithelium is more than twice the depth of the respiratory epithelium, with the olfactory nerve cell bodies typically located in the middle and deeper regions of the epithelium while nuclei of the supporting cells are organized in a single layer closer to the mucosal surface. Tight junctions exist between the supporting cells and between the supporting cells and olfactory nerve cells. Morrison E. E, et al. (1992) Journal of Comparative Neurology 297(1): 1-13.

[0039] When a nasal drug formulation is delivered deep and high enough into the nasal cavity, the olfactory mucosa is reached and drug transport into the brain and/or CSF via the olfactory receptor neurons occurs. The transfer of compounds from the nose to the brain is referred to as the nose-brain pathway. The nose-brain pathway has implications when centrally acting medications such as but not limited to sedatives, anti-seizure drugs, and opiates are delivered nasally. The present device allows for delivery via the nose-brain pathway allowing for nearly immediate delivery of nasal medications to the central nervous system and brain, by passing the blood brain barrier.

[0040] The current challenge in nose-to-brain drug delivery is also due to the complex architecture of the nose, which is naturally designed to channel drugs into the lower nasal airway toward the lungs making it difficult for drugs to reach the olfactory region. Most of the drug dispensed from traditional nasal devices such as sprayers or pumps is subjected to the natural air movement in the nasal cavity towards the esophagus. The majority of the spray dispensed from traditional devices encounters the natural downward airflow displacement within the nasal cavity. The remaining fraction from traditional devices is found in the respiratory epithelium and cleared by the mucocilliary clearance mechanism or absorbed into the blood stream. While nasal catheter instillation and nose drops are less impacted by this natural downward air movement, it requires subjects to be in a supine position, is often associated with user discomfort, and is not optimal for frequent clinical administration.

[0041] Moreover, a reservoir of residual air exists at the top of the nasal cavity that is not removed during normal respiration, thus remaining in the olfactory region and acting as a barrier to deposition. This residual air must be displaced in order to deliver aerosolized drug to the olfactory epithelium in the upper nasal cavity in a consistent manner. The device described herein delivers a majority of the aerosolized drug to the upper part of the nasal cavity to increase exposure of the drug at the olfactory epithelium, a site of nose-to-brain pathway, by both avoiding the natural downward air movement and displacing the residual air of the upper nasal cavity.

[0042] The device herein advantageously and consistently deposits a large fraction of dose into the more distal parts of the nasal cavity such as the olfactory region. A drug product (also referred to herein as drug formulation, drug compound, or intranasal dosage form) is propelled from the device with a velocity into the nasal cavity.

[0043] FIGS. 1A and IB illustrate a perspective view of a nasal drug delivery device 100 and a side view of the device 100 with the nozzle detached, respectively, in accordance with one or more embodiments. The device 100 is designed to deliver a drug compound to an upper nasal cavity of a user. The drug compound may be a liquid, powder, or some combination thereof. In various embodiments, the device 100 may deliver a single dose or a multi-dose, may be single use or reusable, may be manually actuated and propellant-driven, or some combination thereof.

In the embodiments of FIGS. 1A and IB, the device 100 is propellant-driven, delivers a single dose, and may be reused to deliver several individual doses. In the embodiments of FIGS. 1A and IB, the device 100 comprises a housing body 102, a nozzle 104 that contains the drug compound, an actuator 106, and a coupling interface 108 that couples the nozzle 104 to the housing body 102. The nozzle 104 may be coupled to the housing body 102 for delivery of the dose, as shown in FIG. 1A, and may be decoupled from the housing body 102, as shown in FIG. IB, after the drug compound is dispensed into an upper nasal cavity of the user. A new nozzle 104 may be coupled to the housing body 102 for delivery of a subsequent dose.

[0044] The housing body 102 represents the body of the device 100. The housing body 102 is designed to be held in a hand of a user and may include one or more ergonomic features for the comfort of the user. For example, in the embodiment of FIGS. 1A and IB, the housing body 102 includes an indentation 110 that allows a user to comfortably hold and engage the device 100 with the fingers, for example a thumb positioned on the indentation 110 and one or more fingers positioned on top of the actuator 106. In the embodiment of FIGS. 1A and IB, the housing body 102 is composed of two“clamshells” pieces that conceal an internal assembly of the device 100 and retain all of the components in alignment to ensure functionality. A top portion of the housing body 102 couples with the actuator 106 such that the actuator 106 moves relative to the housing body 102. In this configuration, the user may apply a vertical downward force (in the direction of the arrow) to the actuator 106 to actuate the device 100. In alternate embodiments, the housing body 102 and the actuator 106 may be arranged in a different orientation such that the user applies a vertical upward force, a horizontal force, a diagonal force, or some combination thereof to the actuator 106 to actuate the device 100. A stem 112 of the housing body 102 couples to the nozzle 104 via the coupling interface 108.

[0045] The nozzle 104 contains the drug compound. In the embodiment of FIGS. 1A and IB, the nozzle 104 is a single-use nozzle, where the nozzle 104 holds a single dose and may be replaced after each use. The nozzle 104 includes a channel (shown in FIG. 2) that holds the drug compound and an outlet orifice at a distal end (shown in FIG. 2) of the nozzle 104 through which the drug compound may exit the nozzle 104. Housed within the housing body 102 is a propellant canister (shown in FIG. 2) that is in fluid communication with the channel of the nozzle 104, such that propellant released from the canister travels through the nozzle channel and propels the drug compound out the outlet orifice. In the embodiments of FIGS. 1A and IB, the nozzle 104 may be coupled to and decoupled from the stem 112 via the coupling interface 108.

[0046] The actuator 106 is manually actuated by a user to dispense a dose from the nozzle 104. The actuator 106 moves relative to the housing body 102 (e.g., slides, translates, rotates, or other similar motion). In the embodiment of FIGS. 1A and IB, the actuator 106 translates in a vertical motion, represented by the direction of the arrow. The actuator 106 is coupled to the propellant canister (shown in FIG. 2) housed within the housing body 102. In this configuration, actuation of the actuator 106 causes actuation of the propellant canister, thereby releasing propellant that travels through the housing body 102 to the channel of the nozzle 104 and propels the drug compound out the outlet orifice of the nozzle 104.

[0047] The coupling interface 108 couples the nozzle 104 to the housing body 102 and decouples the nozzle 104 from the housing body 102 upon actuation of a release button 116. In the embodiment of FIG. 2, the coupling interface 108 comprises a mating interface 114 on the stem 112, a reciprocal mating interface (shown in FIGS. 4-5) on the nozzle 104, the release button 116 which is directly connected to a securing latch 118, and an opening 120 that receives the securing latch 118. Specifically, the mating interface 114 of the stem 112 couples the reciprocal mating interface of the nozzle 104.

[0048] In the embodiments of FIGS. 1A and IB, the mating interface 114 comprises one or more protruding tabs 121, and the reciprocal mating interface is a receiving cavity, where the receiving cavity receives the one or more protruding tabs 121. In alternate embodiments, the configuration of the receiving cavity and protruding tabs 121 may be reversed (e.g., on opposite components). The mating interface 114 comprises one or more holes 122 such that the securing latch 118 protrudes through a respective hole 122. To couple the nozzle 104 to the housing body 102, the nozzle 104 is positioned onto the stem 112 such that the receiving cavity receives the one or more protruding tabs 121. The opening 120 receives the securing latch 118, which secures the nozzle 104 to the housing body 102. In the embodiments of FIGS. 1A and IB, the securing latch 118 is directly connected to the release button 116, where actuating the release button 116 causes movement of the securing latch 118. To decouple the nozzle 104 from the housing body 102, the release button 116 is actuated, and the securing latch 118 is displaced from the opening 120. The coupling mechanism is discussed in further detail in FIGS. 6-7. In one embodiment, an outer surface of the nozzle 104 and an outer surface of the stem 112 are flush when coupled together.

[0049] In some embodiments, the device 100 includes a dose counter 124. The dose counter 124 tracks the number of actuations of the propellant canister, such that a user may be aware of the amount of propellant remaining in the propellant canister. For example, a propellant canister may have a capacity for distributing propellant for a certain number of doses. In some embodiments, the propellant canister may be replaced with a new propellant canister, such that the device 100 may be reused. In one aspect, when a MDI device is actuated, a discrete amount of pressurized HFA fluid is released. The MDI may contain between about 30 to about 300 actuations, inclusive of endpoints, of HFA propellant. The amount of fluid propellant released upon actuation may be between about 20 microliters (pi) and about 200 microliters (mΐ) inclusive of endpoints, of liquid propellant.

[0050] FIG. 2 illustrates a cross-sectional view of the device of FIGS. 1A and IB, in accordance with one or more embodiments. The cross-sectional view exposes the internal assembly within the housing body 102 and the mating interfaces between the nozzle 104 and the housing body 102. In the embodiment of FIG. 2, the internal assembly comprises a propellant canister 202 and a junction 204 that couples to the nozzle 104, the junction 204 having a propellant channel 206.

[0051] The propellant canister 202 contains propellant. In one embodiment, the propellant may be pressurized. The propellant is a fluid, for example, a liquid or gas. In one aspect, the propellant is a liquid. In another aspect, the propellant is a gas. Propellants include

pharmaceutically suitable propellants. Some examples of pharmaceutically suitable propellants include hydrofluoroalkane (HFA) including but not limited to HFA, HFA 227, HFA 134a, HFA- FP, HFA-BP and the like HFA's. In one aspect, the propellant is liquid HFA. In another aspect, the propellant is gaseous HFA. Additional examples of suitable propellants include nitrogen or choloroflourocarbons (CFC). Additionally, propellants may be pressurized air (e.g. ambient air).

[0052] The canister 202 may be a metered dose inhaler (MDI) device that includes a pressurized canister and metering valve 208 (including stem) to meter the propellant upon actuation. In one embodiment, a pump fitment (not shown) secures the metered valve 208 to the canister 202 and holds both components in place during device 100 use. One series of embodiments of the pump fitment consists of securing interfaces that retain the pump fitment within the housing body 102, provide vertical displacement, and prevent rotation during installation of the canister 202. As shown in FIG. 2, the canister 202 is coupled to the actuator 106. A portion of the canister 202 is positioned within a cavity 210 of the actuator 106 such that movement of the actuator 106 causes actuation of the canister 202 (i.e., the canister 202 moves relative to the metering valve 208, thereby releasing propellant). In the embodiment of FIG. 2, the canister 202 is coupled to the junction 204 such that the metering valve 208 is in fluid communication with the propellant channel 206. In this configuration, the propellant in the canister 202 acts as a vehicle to deliver propulsion or thrust to expel the drug compound from the nozzle 104.

[0053] The junction 204 is an internal structure that couples the canister 202 to the nozzle 104. The propellant channel 206 extends through the junction 204, thereby creating a flow path from the canister 202 to the nozzle 104. As shown in FIG. 2, the junction 204 comprises a base 212, a first branch 214, and a second branch 216. The first branch 214 and the second branch 216 both extend from the base 212. In the embodiment of FIG. 2, the first branch 214 couples to the metering valve 208, and the second branch 216 couples to the nozzle 104. The propellant channel 206 extends from the proximal end of the first branch 214 to the distal end of the second branch 216 and is in fluid communication with the canister 202 and the nozzle 104. Propellant released from the canister 202 travels through the propellant channel 206 to the nozzle 104. In alternate embodiments, the junction 204 may have a varying number of branches that may be in a different arrangement. For example, an angle between the branches may vary between 0 to 180 degrees. In one series of embodiments, the angle is 30 degrees, 35 degrees, 40 degrees, 45 degrees, 50 degrees, 55 degrees, 60 degrees, inclusive of endpoints and intervening degrees.

[0054] The distal end of the second branch 216 couples with the nozzle 104. Specifically, the distal end of the second branch 216 is inserted into a nozzle channel 218 when the nozzle 104 is positioned onto the stem 112. The distal end of the second branch 216 may have a tapered end and/or a chamfer to facilitate insertion into the nozzle channel 218. In the embodiment of FIG. 2, the distal end of the second branch 216 comprises a sealing ring 220 that creates an airtight seal between the junction 204 and an internal surface of the nozzle channel 218. The sealing ring 220 may be an o-ring or an x-ring (lubricated or non-lubricated). In the embodiment of FIG 2, the sealing ring 220 is an x-ring, which has a lower insertion force than an o-ring when the distal end of the second branch 216 is inserted into the nozzle channel 218. Stated differently, an x-ring does not have to deform as much as an o-ring to be positioned within the nozzle channel 218. This configuration decreases both the stiffness of the sealing ring 220 and the potential friction created by the sealing ring 220, which enables a user to easily couple and decouple the nozzle 104 to and from the device 100, thus improving the user experience. In addition, the x-ring is non-lubricated, which prevents lubricant from leeching onto other components of the device 100 or a user of the device.

[0055] As shown in FIG. 2, the nozzle 104 comprises the nozzle channel 218, an outlet orifice 222, and a diffuser 224. The nozzle channel 218 extends between a proximal end and a distal end of the nozzle 104. The outlet orifice 222 is an opening at the distal end of the nozzle 104. The diffuser 224 is positioned within the channel such that the diffuser 224 spans across the diameter of the nozzle channel 218. The drug compound is positioned within the nozzle channel 218 between the diffuser 224 and the outlet orifice 222. In this configuration, the nozzle channel 218 is in fluid communication with the propellant channel 206 such that propellant released from the canister travels through the propellant channel 206, into the nozzle channel 218, contacts the diffuser 224, and propels the drug compound out the outlet orifice 222.

[0056] The diffuser 224 diffuses propellant released from the canister 202. In one aspect, a majority of the propellant is diffused via the diffuser. In another aspect, a minority of the propellant is diffused via the diffuser. Majority refers to and encompasses at least 50 percent. Minority refers to and encompasses less than 50 percent. In another aspect, at least about 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, 99% or about 100%, inclusive of endpoints, of the propellant is diffused via the diffuser. The diffuser 224 is in communication with the nozzle channel 218.

[0057] In some aspects, the diffuser 224 functions to convert propellant from a liquid to a gas. Specifically, the diffuser 224 expands the propellant from a liquid state to a gaseous state. In other aspects, the diffuser 224 functions to prevent the drug compound contained in the nozzle channel 218 from coming in contact with the canister 202. In another aspect, the diffuser acts as a one-way check valve. In other aspects, the diffuser 224 functions to convert propellant from a liquid to a gas and to prevent the compound contained in the nozzle channel 218 from coming into contact with the canister 202. In yet another aspect, the diffuser functions to increase the temperature of the propellant. In one aspect, the diffuser converts the liquid propellant into a gaseous state, which then aerosolizes the drug compound and propels the aerosolized drug compound through the nozzle channel 218 and out the outlet orifice 222.

[0058] An example of a diffuser 224 includes a frit, a plurality of frits, or a diffuser member or combinations thereof. In one aspect, the diffuser is a frit. In another aspect, the diffuser is a plurality of frits. In another aspect, the diffuser is a diffuser member.

[0059] In one aspect, the frit(s) are of any suitable size and shape and are formed using any suitable porous material of any suitable density. In one aspect, the frit is made of a hydrophobic material. In one aspect, the frit is made of an inert material to avoid chemically reacting with any of the compounds. The inert material may be metal or non-metal. In one aspect, the frit is composed of metal. In another aspect, the frit is composed of a non-metal. In one aspect, the inert material is sintered nickel. As one example, a frit formed using a porous stainless steel having a pore size in the range of approximately 1 micron to approximately 100 microns can be used. In another aspect the pore size is in the range of about 1 to about 10, about 10 to about 20, about 20 to about 30, about 30 to about 40, about 40 to about 50, about 50 to about 60, about 60 to about 70, about 70 to about 80, about 80 to about 90, about 90 to about 100 microns, inclusive of endpoints. In another aspect, the frit can be formed using aluminum foam. The number and size of the pores and the overall dimensions (e.g., diameter and thickness) of the frit are set to maximize surface area for vaporization while limiting pressure drops accompanying passage of vaporized propellant through the frit. The frit may be homogenously or heterogeneously porous. In certain aspects, the frit may be constructed of Teflon, glass, metal mesh, screen, porous metal, polyether ether ketone or another plastic material. In one aspect, the passage of liquid propellant through the increased surface area of the frit transitions the liquid to gas and increases the temperature of the resulting gas. In another aspect, the passage of gas propellant through the increased surface area of the frit increases the temperature of the gas.

[0060] FIGS. 3 A and 3B illustrate a side view and a cross-sectional view, respectively, of the internal assembly housed within the device of FIGS. 1A and IB, in accordance with one or more embodiments. As previously described, the internal assembly comprises the propellant canister 202 and the junction 204 having the propellant channel 206. FIGS. 3 A and 3B also show the metering valve 208 and the sealing ring 220.

[0061] FIGS. 4A and 4B illustrate an exploded view and a cross-sectional view, respectively, of a nozzle 400, in accordance with one or more embodiments. The nozzle 400 is an embodiment of the nozzle 104. In the embodiment of FIGS. 4 A and 4B, the nozzle 400 comprises a nozzle body 402, a diffuser 404, and a removable seal 406. The removable seal 406 is a seal that retains the drug compound within the nozzle 400 and may be removed by a user before delivery of the dose. The nozzle body 402 comprises a nozzle channel 408, an outlet orifice 410, a ledge 412, a reciprocal mating interface 414 (for coupling the housing body 102), an opening 416 (for receiving the securing latch 118), a tip seal interface 418, and an ejector sleeve interface 420. For the sake of clarity, the description of corresponding elements in FIGS. 1-3 is incorporated herein for FIGS. 4 A and 4B.

[0062] In the embodiments of FIGS. 4 A and 4B, a diameter of the nozzle channel 408 tapers toward the outlet orifice 410. This configuration may beneficially increase the velocity of the drug compound before it exits the outlet orifice 410. In addition, this configuration may beneficially decrease the plume width, enabling the drug compound to be propelled further into the nasal cavity and into the upper regions of the nasal cavity (e.g., the middle and superior turbinate regions and/or the olfactory region). In alternate embodiments, the nozzle channel 408 may be cylindrical or conical in shape. The design of the nozzle 400 may optimized for various compounds having different characteristics. For example, the diameter of the nozzle channel, the angle and/or shape of the taper, the diameter of the outlet orifice may be modified (e.g., increased or decreased) to suitably deliver the compound to the upper nasal cavity. As an example, larger nozzles may be used for some drug compounds in powder form to prevent clogging within the nozzle.

[0063] The ledge 412 is a surface within the nozzle channel 408 against which the diffuser 404 is seated. In the embodiments of FIGS. 4A and 4B, a proximal portion of the nozzle channel 408 (closer to the propellant channel 206) has a greater diameter than a distal portion of the nozzle channel 408 (closer to the outlet orifice 410), thereby creating the ledge 412 between the two portions. In one embodiment, the proximal portion comprises a tapered or chamfered portion that leads to ledge 412 to facilitate the placement of the diffuser 404 within the nozzle channel 408.

[0064] The tip seal interface 418 is positioned at a tip of the nozzle 400 and couples to the removable seal 406. In the embodiments of FIGS. 4 A and 4B, the tip seal interface 418 is a cavity surrounding the outlet orifice 410 that receives a reciprocal securing interface 422 of the removable seal 406. The removable seal 406 is in the shape of a pull tab but may have other suitable geometries for sealing the outlet orifice 410 and providing a portion that a user may grab to remove the removable seal 406 from the nozzle body 402. In this configuration, the removable seal 406 retains the drug compound within the nozzle channel 408 and prevents the drug compound from prematurely coming out of the outlet orifice 410. The removable seal 406 also maintains the integrity of the drug compound (i.e., preventing contamination) until the dose is to be delivered. In one embodiment, a portion of the removable seal 406 inserts into the outlet orifice 410. Accordingly, the drug compound is secured within the nozzle channel 408 between the diffuser 404 and the removable seal 406. The removable seal 406 may be removed (e.g., by twisting, pulling, tearing, or similar) from the tip seal interface 418 once the dose is ready to be delivered to a user’s upper nasal cavity.

[0065] The ejector sleeve interface 420 is configured to couple to an ejector sleeve, which is described in further detail in FIGS. 6A and 6B. The ejector sleeve is a component of the coupling mechanism that enables the nozzle 400 to decouple from the housing body 102. In the embodiments of FIGS. 4A and 4B, the ejector sleeve interface 420 is a ledge about an external surface of the nozzle channel 408. The ejector sleeve is a ring-like structure (shown in FIG. 6A) that slides onto and mates with the ejector sleeve interface 420.

[0066] FIGS. 5 A and 5B illustrate an exploded view and a cross-sectional view, respectively, of a nozzle, in accordance with one or more embodiments. The nozzle 500 is an embodiment of the nozzle 104 or the nozzle 400. In the embodiment of FIGS. 5A and 5B, the nozzle 500 comprises a nozzle body 502, a diffuser 504, and a removable seal 506. The nozzle body 502 comprises a nozzle channel 508, an outlet orifice 510, a ledge 512, a reciprocal mating interface 514 (for coupling the housing body 102), an opening 516 (for receiving the securing latch 118), a tip seal interface 518, and an ejector sleeve interface 520. For the sake of clarity, the description of corresponding elements in FIGS. 1-4 is incorporated herein for FIGS. 5 A and 5B.

[0067] In the embodiments of FIGS. 5 A and 5B, the removable seal 506 is in the shape of a foil tab that may be adhered to the tip seal interface 518, which is a surface surrounding the outlet orifice 510. In other embodiments, the removable seal 506 may have other suitable geometries for sealing the outlet orifice 410 and providing a portion that a user may grab to remove the removable seal 406 from the nozzle body 402.

[0068] FIGS. 6A and 6B illustrate an exploded view of the internal assembly and the internal assembly seated within a portion of the housing body 102, respectively, in accordance with one or more embodiments. In FIG. 6A, additional components of the coupling mechanism for coupling and decoupling the nozzle 104 to and from the housing body 102 are shown. In the embodiment of FIGS. 6A and 6B, the coupling mechanism enables the nozzle 104 to be positioned on and secured to a distal end of the stem 112 and enables the nozzle 104 to be released from the stem 112 upon depression of the release button 116. In particular, the coupling mechanism retains the nozzle 104 on the distal end of the stem 112 after the nozzle 104 is released to prevent the nozzle 104 from fully ejecting off the stem 112. These components comprise a compression spring 602 and an ejector sleeve 604.

[0069] The compression spring 602 is positioned about a distal end of the second branch of the junction. In the embodiments of FIGS. 6A and 6B, a first end of the compression spring 602 is coupled to the second branch via one or more engagement ribs 606, and a second end of the compression spring 602 is coupled to the ejector sleeve 604. In FIG. 6A, the compression spring 602 is shown at its full length (at rest). The compression spring 602 may be compressed when a force is applied to it.

[0070] The ejector sleeve 604 couples to an ejector sleeve interface of a nozzle (as described in FIGS. 4A and 4B). In the embodiment of FIGS. 6A and 6B, the ejector sleeve 604 is a ring like structure that mates with the ejector sleeve interface of the nozzle. A proximal end of the ejector sleeve 604 is coupled to the compression spring 602 such that the ejector sleeve 604 moves with the compression spring 602 as the compression spring 602 is fully compressed, partially compressed, or returning to a resting length. FIG. 6B illustrates the internal assembly seated within a portion of the housing body 102, where the compression spring 602 is partially compressed such that the ejector sleeve 604 may be positioned within the housing body 102. In some embodiments, the compression spring 602 may be at rest when positioned within the housing body 102.

[0071] When a nozzle is coupled to the housing body 102, the nozzle couples to the ejector sleeve 604 and compresses the compression spring 602 such that the securing latch of the release button mates with the opening on the nozzle. In this configuration, the ejector sleeve 604 moves between a first position, in which the compression spring 602 is partially compressed, and a second position, in which the compression spring 602 is further partially compressed or fully compressed. In one embodiment, the ejector sleeve 604 moves between a first position, in which the compression spring 602 is at rest, and a second position, in which the compression spring 602 is partially compressed or fully compressed. The ejector sleeve 604 transitions between the first position and the second position as the nozzle is being coupled to the housing body 102 or as the nozzle is being decoupled from the housing body 102.

[0072] As previously described, to decouple the nozzle from the housing body 102, a user provides user input to the release button 116, which displaces the securing latch from the opening in the nozzle. Once the securing latch is displaced from the nozzle opening, the ejector sleeve 604 transitions from the second position to the first position. In the embodiment of FIGS. 6A and 6B, a protrusion (e.g., in the shape of a wedge or ramp) on an internal surface of a first side of the housing body 102 contacts the ejector sleeve 604 and biases the movement of the ejector sleeve 604 towards a second side of the housing body 102. Thus, as the ejector sleeve 604 transitions from the second position to the first position, the nozzle coupled to the ejector sleeve 604 abuts the second side of the housing body 102. In this configuration, friction created between the nozzle and the side of the housing body 102 prevents the nozzle from fully ejecting from the housing body 102 (i.e., launching off of the housing body 102) such that the nozzle remains on a distal portion of the stem 112 once decoupled from the housing body 102, enabling a user to manually remove the decoupled nozzle from the stem 112.

[0073] FIGS. 7A-7C illustrate an internal surface 702 of the housing body 102 and a release button 704, in accordance with one or more embodiments. In the embodiments of FIGS. 7A-7C, the release button 704 is coupled to the internal surface 702, specifically an internal surface of the stem 112 which comprises an opening 706 for exposing the release button 704. The release button 704 is positioned such that a securing latch 708 directly connected to the release button 704 protrudes through the opening 706 in the mating interface 114. The release button 704 may have one or more locating features 710 that mate with reciprocal locating features 712 on the internal surface 702 for fine tune alignment of the release button 704. In one embodiment, the release button 704 is molded with a bend such that, when the device is assembled and the junction 204 is positioned against the release button 704, the securing latch is pre-loaded to better retain the nozzle.

[0074] FIG. 8 a perspective, partially exploded view of the device of FIGS. 1A and IB, in accordance with one or more embodiments. FIG. 8 illustrates the housing body 102 with the actuator 106 removed and without a nozzle. In some embodiments, the propellant canister 202 may be replaced such that the device 100 may be reused. Additional Configuration Information

[0075] The foregoing description of the embodiments of the disclosure has been presented for the purpose of illustration; it is not intended to be exhaustive or to limit the disclosure to the precise forms disclosed. Persons skilled in the relevant art can appreciate that many

modifications and variations are possible in light of the above disclosure.

[0076] The language used in the specification has been principally selected for readability and instructional purposes, and it may not have been selected to delineate or circumscribe the inventive subject matter. It is therefore intended that the scope of the disclosure be limited not by this detailed description, but rather by any claims that issue on an application based hereon. Accordingly, the disclosure of the embodiments is intended to be illustrative, but not limiting, of the scope of the disclosure, which is set forth in the following claims.