SOLID STATE FORMS OF FIRIBASTAT AND PROCESSES FOR PREPARATION THEREOF

FIELD OF THE DISCLOSURE

[0001] The present disclosure encompasses solid state forms of Firibastat and salts or co crystals thereof, processes for preparation thereof, and pharmaceutical compositions thereof.

BACKGROUND OF THE DISCLOSURE

[0002] Firibastat, (Sri^AFd^-DithiobisP-amino-l-butanesulfonic acid], has the following chemical structure:

[0003] Firibastat is a prodrug of the APA inhibitor EC33, an inhibitor of aminopeptidase A, and it is developed for the treatment of hypertension.

[0004] The compound is described in International Publication No. WO 2004/007441. Crystalline Firibastat is disclosed in International Publication No. WO 2012/045849 and a crystalline phase of Firibastat with L-lysine is disclosed in International Publication No. WO 2014/064077.

[0005] Polymorphism, the occurrence of different crystalline forms, is a property of some molecules and molecular complexes. A single molecule may give rise to a variety of polymorphs having distinct crystal structures and physical properties like melting point, thermal behaviors (e.g., measured by thermogravimetric analysis (“TGA”), or differential scanning calorimetry (“DSC”)), X-ray diffraction (XRD) pattern, infrared absorption fingerprint, and solid state ( ¹³ C) NMR spectrum. One or more of these techniques may be used to distinguish different polymorphic forms of a compound.

[0006] Different salts and solid state forms (including solvated forms) of an active pharmaceutical ingredient may possess different properties. Such variations in the properties of different salts and solid state forms and solvates may provide a basis for improving formulation, for example, by facilitating better processing or handling characteristics, changing the dissolution profile in a favorable direction, or improving stability (polymorph as well as chemical stability) and shelf-life. These variations in the properties of different salts and solid state forms may also offer improvements to the final dosage form, for instance, if they serve to improve bioavailability. Different salts and solid state forms and solvates of an active pharmaceutical ingredient may also give rise to a variety of polymorphs or crystalline forms, which may in turn provide additional opportunities to assess variations in the properties and characteristics of a solid active pharmaceutical ingredient.

[0007] Discovering new solid state forms and solvates of a pharmaceutical product may yield materials having desirable processing properties, such as ease of handling, ease of processing, storage stability, and ease of purification or as desirable intermediate crystal forms that facilitate conversion to other polymorphic forms. New solid state forms of a pharmaceutically useful compound can also provide an opportunity to improve the performance characteristics of a pharmaceutical product. It enlarges the repertoire of materials that a formulation scientist has available for formulation optimization, for example by providing a product with different properties, including a different crystal habit, higher crystallinity, or polymorphic stability, which may offer better processing or handling characteristics, improved dissolution profile, or improved shelf-life (chemical/physical stability). For at least these reasons, there is a need for additional solid state forms (including solvated forms) of Firibastat.

SUMMARY OF THE DISCLOSURE

[0008] The present disclosure provides crystalline polymorphs of Firibastat, as well as co crystals and/or salts of Firibastat; processes for preparation thereof, and pharmaceutical compositions thereof. These crystalline polymorphs and crystalline salts and co-crystals can be used to prepare other solid state forms of Firibastat, Firibastat co-crystals, Firibastat salts and their solid state forms.

[0009] The present disclosure also provides uses of the said solid state forms of Firibastat, Firibastat co-crystals and/or Firibastat salts in the preparation of other solid state forms of Firibastat or Firibastat co-crystals or salts thereof.

[0010] The present disclosure also provides the said solid state forms of Firibastat, Firibastat, co-crystals and/or Firibastat salts for use in the preparation of other solid state forms of Firibastat, or Firibastat, co-crystals or salts thereof. [0011] The present disclosure provides crystalline polymorphs of Firibastat, as well as co crystals and/or salts of Firibastat for use in the preparation of pharmaceutical compositions and/or formulations for use in medicine, including for the treatment of hypertension.

[0012] The present disclosure also encompasses the use of crystalline polymorphs of Firibastat, Firibastat co-crystals and/or Firibastat salts of the present disclosure for the preparation of pharmaceutical compositions and/or formulations.

[0013] In another aspect, the present disclosure provides pharmaceutical compositions including crystalline polymorphs of Firibastat, Firibastat co-crystals and/or Firibastat salts according to the present disclosure.

[0014] In yet another embodiment, the present disclosure encompasses pharmaceutical formulations including any one or a combination of the crystalline polymorphs of Firibastat, Firibastat co-crystals and/or Firibastat salts or pharmaceutical compositions including the described crystalline polymorphs of Firibastat, Firibastat co-crystals and/or Firibastat salts and at least one pharmaceutically acceptable excipient.

[0015] The present disclosure includes processes for preparing the above mentioned pharmaceutical compositions. The processes include combining any one or a combination of the crystalline polymorphs of Firibastat, Firibastat co-crystals and/or Firibastat salts with at least one pharmaceutically acceptable excipient.

[0016] The crystalline polymorphs of Firibastat, as well as co-crystals and/or salts of Firibastat as defined herein and the pharmaceutical compositions or formulations of the crystalline polymorph of Firibastat, Firibastat co-crystals and/or Firibastat salts may be used as medicaments, such as for the treatment of hypertension.

[0017] The present disclosure also provides methods of treating hypertension, by administering a therapeutically effective amount of any one or a combination of the crystalline polymorphs of Firibastat, Firibastat co-crystals and/or Firibastat salts of the present disclosure, or at least one of the above pharmaceutical compositions, to a subject suffering from hypertension, or otherwise in need of the treatment.

[0018] The present disclosure also provides uses of crystalline polymorphs of Firibastat, Firibastat co-crystals and/or Firibastat salts of the present disclosure, or at least one of the above pharmaceutical compositions, for the manufacture of medicaments for treating e.g., hypertension. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 shows a characteristic X-ray powder diffraction pattern (XRPD) of Firibastat Form HI;

[0020] Figure 2 shows a characteristic X-ray powder diffraction pattern (XRPD) of Firibastat Form H2;

[0021] Figure 3 shows a characteristic X-ray powder diffraction pattern (XRPD) of Firibastat Form A;

[0022] Figure 4 shows a characteristic X-ray powder diffraction pattern (XRPD) of Firibastat Form B;

[0023] Figure 5 shows a characteristic X-ray powder diffraction pattern (XRPD) of Firibastat crystal Form El;

[0024] Figure 6 shows a characteristic X-ray powder diffraction pattern (XRPD) of Firibastat: piperazine Form PI;

[0025] Figure 7 shows a characteristic X-ray powder diffraction pattern (XRPD) of Firibastat: L-proline Form P2;

[0026] Figure 8 shows a characteristic solid state ¹³ C-NMR of Firibastat Form A (200-0 ppm);

[0027] Figure 8A shows a characteristic solid state ¹³ C-NMR of Firibastat Form A (100-0 ppm);

[0028] Figure 9 shows a characteristic solid state ¹³ C-NMR of Firibastat crystal Form El (200-0 ppm); and

[0029] Figure 9 A shows a characteristic solid state ¹³ C-NMR of Firibastat crystal Form EIQOO-O ppm).

DETAILED DESCRIPTION OF THE DISCLOSURE

[0030] The present disclosure provides crystalline polymorphs of Firibastat, as well as co crystals and/or salts of Firibastat; processes for preparation thereof, and pharmaceutical compositions thereof.

[0031] Solid state properties of Firibastat and crystalline polymorphs thereof can be influenced by controlling the conditions under which Firibastat and crystalline polymorphs thereof are obtained in solid form. [0032] A solid state form (or polymorph) may be referred to herein as polymorphically pure or as substantially free of any other solid state (or polymorphic) forms. As used herein in this context, the expression "substantially free of any other forms" will be understood to mean that the solid state form contains about 20% (w/w) or less, about 10% (w/w) or less, about 5% (w/w) or less, about 2% (w/w) or less, about 1% (w/w) or less, or about 0% of any other forms of the subject compound as measured, for example, by XRPD. Thus, a crystalline polymorph of Firibastat described herein as substantially free of any other solid state forms would be understood to contain greater than about 80% (w/w), greater than about 90% (w/w), greater than about 95% (w/w), greater than about 98% (w/w), greater than about 99% (w/w), or about 100% of the subject crystalline polymorph of Firibastat In some embodiments of the disclosure, the described crystalline polymorph of Firibastat may contain from about 1% to about 20% (w/w), from about 5% to about 20% (w/w), or from about 5% to about 10% (w/w) of one or more other crystalline polymorph of the same Firibastat.

[0033] Depending on which other crystalline polymorphs a comparison is made, the crystalline polymorphs of Firibastat of the present disclosure may have advantageous properties selected from at least one of the following: chemical purity, flowability, solubility, dissolution rate, morphology or crystal habit, stability, such as chemical stability as well as thermal and mechanical stability with respect to polymorphic conversion, stability towards dehydration and/or storage stability, low content of residual solvent, a lower degree of hygroscopicity, flowability, and advantageous processing and handling characteristics such as compressibility and bulk density. Particularly, the crystalline polymorph as described in any aspect or embodiment of the present disclosure may be stable, for example to conditions of high relative humidity, and/or may be thermally stable. Crystalline Forms A, B, El, PI and P2 as described in any aspect or embodiment of the present disclosure, may be especially stable to conditions of high relative humidity and/or may be thermally stable.

[0034] A solid state form, such as a crystal form or an amorphous form, may be referred to herein as being characterized by graphical data “as depicted in” or “as substantially depicted in” a Figure. Such data include, for example, powder X-ray diffractograms and solid state NMR spectra. As is well-known in the art, the graphical data potentially provides additional technical information to further define the respective solid state form (a so-called “fingerprint”) which cannot necessarily be described by reference to numerical values or peak positions alone. In any event, the skilled person will understand that such graphical representations of data may be subject to small variations, e.g., in peak relative intensities and peak positions due to certain factors such as, but not limited to, variations in instrument response and variations in sample concentration and purity, which are well known to the skilled person. Nonetheless, the skilled person would readily be capable of comparing the graphical data in the Figures herein with graphical data generated for an unknown crystal form and confirm whether the two sets of graphical data are characterizing the same crystal form or two different crystal forms. A crystal form of Firibastat referred to herein as being characterized by graphical data “as depicted in” or “as substantially depicted in” a Figure will thus be understood to include any crystal forms of Firibastat characterized with the graphical data having such small variations, as are well known to the skilled person, in comparison with the Figure.

[0035] As used herein, and unless stated otherwise, the term “anhydrous” in relation to crystalline forms of Firibastat, relates to a crystalline form of Firibastat which does not include any crystalline water (or other solvents) in a defined, stoichiometric amount within the crystal. Moreover, an “anhydrous” form would generally not contain more than 1% (w/w), of either water or organic solvents as measured for example by TGA.

[0036] The term "solvate," as used herein and unless indicated otherwise, refers to a crystal form that incorporates a solvent in the crystal structure. When the solvent is water, the solvate is often referred to as a "hydrate." The solvent in a solvate may be present in either a stoichiometric or in a non-stoichiometric amount.

[0037] "Co-Crystal" or "Co-crystal" as used herein is defined as a crystalline material including two or more molecules in the same crystalline lattice and associated by non-ionic and non-covalent bonds. In some embodiments, the co-crystal includes two molecules which are in natural state.

[0038] As used herein, crystalline Firibastat: piperazine is a distinct molecular species Crystalline Firibastat: piperazine may be a co-crystal of Firibastat and piperazine. Alternatively crystalline Firibastat: piperazine may be a salt (Firibastat piperazinium). Preferably, Firibastat: piperazine is a salt. In embodiments the molar ratio between Firibastat and piperazine is between 1: 1.5 and 1.5: 1, preferably between 1: 1.25 and 1.25: 1, about 1:2 or in other embodiments about 1:1, and preferably about 1:2. [0039] As used herein, crystalline Firibastat: L-Proline is a distinct molecular species and/or a distinct crystalline phase. Crystalline Firibastat: L-Proline may be a co-crystal of Firibastat and L-Proline. Alternatively, crystalline Firibastat: L-Proline may be a salt. In embodiments the molar ratio between the active pharmaceutical ingredient (Firibastat) and the coformer (L- Proline) is between 1:3 and 3:1, preferably between 1:2.5 and 2.5:1, in other embodiments about 1:2.

[0040] As used herein, the term "isolated" in reference to crystalline polymorph of Firibastat, of the present disclosure corresponds to a crystalline polymorph of Firibastat that is physically separated from the reaction mixture in which it is formed.

[0041] As used herein, unless stated otherwise, the XRPD measurements are taken using copper Kal radiation wavelength 1.54060 A. XRPD peaks reported herein are measured using CuK al radiation, l = 1.54060 A, typically at a temperature of 25 ± 3°C.

[0042] As used herein, unless stated otherwise, ¹³ C NMR reported herein are measured at 11.7 T at a magic angle spinning frequency w _G /2p = 18 kHz, preferably at a temperature of at 293 K ± 3°C.

[0043] A thing, e.g., a reaction mixture, may be characterized herein as being at, or allowed to come to “room temperature” or “ambient temperature,” often abbreviated as “RT.” This means that the temperature of the thing is close to, or the same as, that of the space, e.g., the room or fume hood, in which the thing is located. Typically, room temperature is from about 20°C to about 30°C, or about 22°C to about 27°C, or about 25°C.

[0044] The amount of solvent employed in a chemical process, e.g., a reaction or crystallization, may be referred to herein as a number of “volumes” or “vol” or “V.” For example, a material may be referred to as being suspended in 10 volumes (or 10 vol or 10V) of a solvent. In this context, this expression would be understood to mean milliliters of the solvent per gram of the material being suspended, such that suspending a 5 grams of a material in 10 volumes of a solvent means that the solvent is used in an amount of 10 milliliters of the solvent per gram of the material that is being suspended or, in this example, 50 mL of the solvent. In another context, the term "v/v" may be used to indicate the number of volumes of a solvent that are added to a liquid mixture based on the volume of that mixture. For example, adding solvent X (1.5 v/v) to a 100 ml reaction mixture would indicate that 150 mL of solvent X was added. [0045] A process or step may be referred to herein as being carried out "overnight." This refers to a time interval, e.g., for the process or step, that spans the time during the night, when that process or step may not be actively observed. This time interval is from about 8 to about 20 hours, or about 10-18 hours, in some cases about 16 hours.

[0046] As used herein, the term “reduced pressure” refers to a pressure that is less than atmospheric pressure. For example, reduced pressure is about 10 mbar to about 50 mbar.

[0047] As used herein and unless indicated otherwise, the term "ambient conditions" refer to atmospheric pressure and a temperature of 22-24°C.

[0048] The present disclosure includes a crystalline polymorph of Firibastat, designated Form HI. Crystalline Form HI of Firibastat may be characterized by data selected from one or more of the following: an X-ray powder diffraction pattern substantially as depicted in Figure 1; an X-ray powder diffraction pattern having peaks at 17.8, 18.6, 19.6, 21.7 and 24.4 degrees 2- theta ± 0.2 degrees 2-theta; and combinations of these data.

[0049] Crystalline Form HI of Firibastat may be further characterized by an X-ray powder diffraction pattern having peaks at 17.8, 18.6, 19.6, 21.7 and 24.4 degrees 2-theta ± 0.2 degrees 2-theta, and also having any one, two, three, four or five additional peaks selected from 18.0, 20.4, 21.9, 23.2 and 26.2 degrees 2-theta ± 0.2 degrees 2-theta.

[0050] Crystalline Form HI of Firibastat may be alternatively characterized by an X-ray powder diffraction pattern having peaks at 17.8, 18.0, 18.6, 19.6, 20.4, 21.7, 21.9, 23.2, 24.4 and 26.2 degrees 2-theta ± 0.2 degrees 2-theta.

[0051] In embodiments of the present disclosure, crystalline Form HI of Firibastat is isolated. Particularly, crystalline Form HI of Firibastat according to any aspect or embodiment of the disclosure may be isolated.

[0052] Crystalline Form HI of Firibastat may be a hydrate. In embodiments, crystalline Form HI may contain about 0.5 % to about 5 % of water.

[0053] Crystalline Form HI may be polymorphically pure.

[0054] Crystalline Form HI of Firibastat may be characterized by each of the above characteristics alone or by all possible combinations, e.g., an XRPD pattern having peaks at 17.8, 18.6, 19.6, 21.7 and 24.4 degrees 2-theta ± 0.2 degrees 2-theta; an XRPD pattern as depicted in Figure 1; and combinations thereof. [0055] The present disclosure includes a crystalline polymorph of Firibastat, designated Form H2. Crystalline Form H2 of Firibastat may be characterized by data selected from one or more of the following: an X-ray powder diffraction pattern substantially as depicted in Figure 2; an X-ray powder diffraction pattern having peaks at 16.0, 18.4, 18.8, 24.3 and 26.2 degrees 2- theta ± 0.2 degrees 2-theta; and combinations of these data.

[0056] Crystalline Form H2 of Firibastat may be further characterized by an X-ray powder diffraction pattern having peaks at 16.0, 18.4, 18.8, 24.3 and 26.2 degrees 2-theta ± 0.2 degrees 2-theta, and also having any one, two, three, four or five additional peaks selected from 14.5, 20.2, 21.4, 22.5 and 28.6 degrees 2-theta ± 0.2 degrees 2-theta.

[0057] Crystalline Form HI of Firibastat may be alternatively characterized by an X-ray powder diffraction pattern having peaks at 14.5, 16.0, 18.4, 18.8, 20.2, 21.4, 22.5, 24.3, 26.2 and 28.6 degrees 2-theta ± 0.2 degrees 2-theta.

[0058] In embodiments of the present disclosure, crystalline Form H2 of Firibastat is isolated. Particularly, crystalline Form H2 of Firibastat according to any aspect or embodiment of the disclosure may be isolated.

[0059] Crystalline Form H2 of Firibastat may be a hydrate. In embodiments, crystalline Form H2 may contain about 6 % to about 10% of water.

[0060] Crystalline Form H2 of Firibastat may be characterized by each of the above characteristics alone or by all possible combinations, e.g., an XRPD pattern having peaks at 16.0, 18.4, 18.8, 24.3 and 26.2 degrees 2-theta ± 0.2 degrees 2-theta; an XRPD pattern as depicted in Figure 2; and combinations thereof.

[0061] Crystalline Form H2 may be polymorphically pure.

[0062] The present disclosure includes a crystalline polymorph of Firibastat, designated Form A. Crystalline Form A of Firibastat may be characterized by data selected from one or more of the following: an X-ray powder diffraction pattern substantially as depicted in Figure 3; an X-ray powder diffraction pattern having peaks at 11.2, 16.3, 17.8, 19.9 and 23.4 degrees 2- theta ± 0.2 degrees 2-theta; a solid state ¹³ C NMR spectrum having characteristic peaks at 49.9, 49.0, 46.3, 42.9, 39.5, 31.0 and 26.9 ppm ± 0.2 ppm; a solid state ¹³ C NMR spectrum substantially as depicted in Figure 8 or in Figure 8A; and combinations of these data.

[0063] Crystalline Form A of Firibastat may be further characterized by an X-ray powder diffraction pattern having peaks at 11.2, 16.3, 17.8, 19.9 and 23.4 degrees 2-theta ± 0.2 degrees 2-theta, and also having any one, two, three, four or five additional peaks selected from 18.8, 21.7, 22.3, 26.6 and 27.2 degrees 2-theta ± 0.2 degrees 2-theta.

[0064] Crystalline Form A of Firibastat may be alternatively characterized by an X-ray powder diffraction pattern having peaks at 11.2, 16.3, 17.8, 18.8, 19.9, 21.7, 22.3, 23.4, 26.6 and 27.2 degrees 2-theta ± 0.2 degrees 2-theta.

[0065] In embodiments of the present disclosure, crystalline Form A of Firibastat is isolated. Particularly, crystalline Form A of Firibastat according to any aspect or embodiment of the disclosure may be isolated.

[0066] Crystalline Form A of Firibastat may be anhydrous.

[0067] Crystalline Form A of Firibastat may be polymorphically pure.

[0068] Crystalline Form A of Firibastat may be characterized by each of the above characteristics alone or by all possible combinations, e.g., an XRPD pattern having peaks at 11.2,

16.3, 17.8, 19.9 and 23.4 degrees 2-theta ± 0.2 degrees 2-theta; an XRPD pattern as depicted in Figure 3; and combinations thereof.

[0069] Crystalline Form A according to any aspect or embodiment of the disclosure may be particularly stable, e.g. thermally stable, stable to high relative humidity, stable to grinding, and/or stable to compression.

[0070] The present disclosure includes a crystalline polymorph of Firibastat, designated Form B. Crystalline Form B of Firibastat may be characterized by data selected from one or more of the following: an X-ray powder diffraction pattern substantially as depicted in Figure 4; an X-ray powder diffraction pattern having peaks at 9.4, 13.3, 18.5, 20.1 and 23.3 degrees 2- theta ± 0.2 degrees 2-theta; and combinations of these data.

[0071] Crystalline Form B of Firibastat may be further characterized by an X-ray powder diffraction pattern having peaks at 9.4, 13.3, 18.5, 20.1 and 23.3 degrees 2-theta ± 0.2 degrees 2- theta, and also having any one, two, three, four or five additional peaks selected from 17.6, 17.9,

22.3, 24.1 and 25.5 degrees 2-theta ± 0.2 degrees 2-theta.

[0072] Crystalline Form B of Firibastat may be alternatively characterized by an X-ray powder diffraction pattern having peaks at 9.4, 13.3, 17.6, 17.9, 18.5, 20.1, 22.3, 23.3, 24. land 25.5 degrees 2-theta ± 0.2 degrees 2-theta. [0073] In embodiments of the present disclosure, crystalline Form B of Firibastat is isolated. Particularly, crystalline Form B of Firibastat according to any aspect or embodiment of the disclosure may be isolated.

[0074] Crystalline Form B of Firibastat may be polymorphically pure.

[0075] Crystalline Form B of Firibastat may be characterized by each of the above characteristics alone or by all possible combinations, e.g., an XRPD pattern having peaks at 9.4, 13.3, 18.5, 20.1 and 23.3 degrees 2-theta ± 0.2 degrees 2-theta; an XRPD pattern as depicted in Figure 4; and combinations thereof.

[0076] Crystalline Form B according to any aspect or embodiment of the disclosure may be particularly stable, e.g. stable to high relative humidity, stable to grinding, and/or stable to compression.

[0077] The disclosure further encompasses a crystalline form of Firibastat designated Form El. Firibastat crystal Form El may be characterized by data selected from one or more of the following: an X-ray powder diffraction pattern substantially as depicted in Figure 5; an X-ray powder diffraction pattern having peaks at 11.8, 18.1, 20.6, 21.3 and 24.6 degrees 2-theta ± 0.2 degrees 2-theta; a solid state ¹³ C NMR spectrum having characteristic peaks at 29.4, 37.9, 44.9, 47.0, and 50.3 ppm ± 0.2 ppm; a solid state ¹³ C NMR spectrum substantially as depicted in Figure 9 or in Figure 9A; and combinations of these data.

[0078] Crystalline Form El of Firibastat as described in any embodiment disclosed herein may be further characterized by an X-ray powder diffraction pattern having peaks at 11.8, 18.1, 20.6, 21.3 and 24.6 degrees 2-theta ± 0.2 degrees 2-theta, and also having any one, two, three, four or five additional peaks selected from 22.3, 22.9, 23.3, 23.7 and 27.3 degrees 2-theta ± 0.2 degrees 2-theta.

[0079] Firibastat crystalline Form El as described in any aspect or embodiment of the present disclosure is obtainable by a process according to any of Example 6, Procedures A, B, C or D. The present disclosure therefore encompasses Firibastat crystal Form El obtainable by a process according to any of Example 6, Procedures A, B, C or D.

[0080] In embodiments of the present disclosure, crystalline Form El of Firibastat is isolated. Particularly, Firibastat crystalline Form El according to any aspect or embodiment of the disclosure may be isolated.

[0081] Firibastat crystalline Form El may be a hydrate. [0082] Crystalline Form El of Firibastat may be polymorphically pure.

[0083] Crystalline Form El of Firibastat may be characterized by each of the above characteristics alone or by all possible combinations, e.g., an XRPD pattern having peaks at 11.8, 18.1, 20.6, 21.3 and 24.6 degrees 2-theta ± 0.2 degrees 2-theta; an XRPD pattern as depicted in Figure 5; and combinations thereof.

[0084] Crystalline Form El according to any aspect or embodiment of the disclosure may be particularly stable, e.g. stable to high relative humidity, stable to grinding, and/or stable to compression.

[0085] The disclosure further encompasses a crystalline form of Firibastat: piperazine, designated Form PI. Crystalline Form PI of Firibastat: piperazine is a distinct molecular species. Crystalline Form PI of Firibastat: piperazine may be a co-crystal of Firibastat and piperazine. Alternatively crystalline Form PI of Firibastat: piperazine may be a salt (Firibastat piperazinium or Firibastat piperazine salt). Preferably, Form PI of Firibastat: piperazine is a salt. In embodiments the molar ratio between Firibastat and piperazine is between 1: 1.5 and 1.5: 1, preferably between 1: 1.25 and 1.25: 1, about 1:2, or about 1:1, preferably about 1:2.

[0086] Crystalline Form PI of Firibastat: piperazine may be characterized by data selected from one or more of the following: an X-ray powder diffraction pattern substantially as depicted in Figure 6; an X-ray powder diffraction pattern having peaks at 12.5, 16.4, 17.6, 19.5 and 22.1 degrees 2-theta ± 0.2 degrees 2-theta; and combinations of these data.

[0087] Crystalline Form PI of Firibastat: piperazine may be further characterized by an X- ray powder diffraction pattern having peaks at 12.5, 16.4, 17.6, 19.5 and 22.1 degrees 2-theta ± 0.2 degrees 2-theta, and also having any one, two, three, four or five additional peaks selected from 15.7, 20.0, 20.7, 25.1 and 27.7 degrees 2-theta ± 0.2 degrees 2-theta.

[0088] Crystalline Form PI of Firibastat: piperazine may be alternatively characterized by an X-ray powder diffraction pattern having peaks at 12.5, 15.7, 16.4, 17.6, 19.5, 20.0, 20.7, 22.1, 25.1 and 27.7 degrees 2-theta ± 0.2 degrees 2-theta.

[0089] Firibastat: Piperazine crystal Form PI as described in any aspect or embodiment of the present disclosure is obtainable by a process according to any of Example 7, Procedures A, B or C. The present disclosure therefore encompasses Firibastat: Piperazine crystal Form PI obtainable by a process according to any of Example 7, Procedures A, B or C. [0090] In embodiments of the present disclosure, crystalline Form PI of Firibastat: piperazine is isolated. Particularly, crystalline Form PI of Firibastat: piperazine according to any aspect or embodiment of the disclosure may be isolated.

[0091] Crystalline Form PI of Firibastat: piperazine may be polymorphically pure.

[0092] Crystalline Form PI of Firibastat: piperazine may be characterized by each of the above characteristics alone or by all possible combinations, e.g., an XRPD pattern having peaks at 12.5, 16.4, 17.6, 19.5 and 22.1 degrees 2-theta ± 0.2 degrees 2-theta; an XRPD pattern as depicted in Figure 6; and combinations thereof.

[0093] Crystalline Form PI according to any aspect or embodiment of the disclosure may be particularly stable, e.g. stable to high relative humidity, stable to grinding, and/or stable to compression.

[0094] The disclosure further encompasses a crystalline phase of Firibastat: L-Proline, designated Form P2. Crystalline Form P2 of Firibastat: L-proline crystalline phase is a distinct molecular species. In embodiments crystalline Firibastat: L-Proline may be a co-crystal of Firibastat and L-Proline. Alternatively, crystalline Firibastat: L-Proline may be a salt. In embodiments the molar ratio between the active pharmaceutical ingredient (Firibastat) and the coformer (L-Proline) is between 1:3 and 3:1, preferably between 1:2.5 and 2.5:1, in other embodiments about 1:2.

[0095] Crystalline Form P2 of Firibastat: L-Proline may be characterized by data selected from one or more of the following: an X-ray powder diffraction pattern substantially as depicted in Figure 7; an X-ray powder diffraction pattern having peaks at 12.9, 17.8, 20.2, 23.5 and 25.7 degrees 2-theta ± 0.2 degrees 2-theta; a solid state ¹³ C NMR spectrum substantially as depicted in Figure 10; and combinations of these data.

[0096] Crystalline Form P2 of Firibastat: L-Proline may be further characterized by an X-ray powder diffraction pattern having peaks at 12.9, 17.8, 20.2, 23.5 and 25.7 degrees 2-theta ± 0.2 degrees 2-theta, and also having any one, two, three, four or five additional peaks selected from 18.5, 19.0, 19.7, 21.3 and 21.9 degrees 2-theta ± 0.2 degrees 2-theta.

[0097] Crystalline Form P2 of Firibastat: L-proline may be alternatively characterized by an X-ray powder diffraction pattern having peaks at 12.9, 17.8, 18.5, 19.0, 19.7, 20.2, 21.3, 21.9 23.5 and 25.7 degrees 2-theta ± 0.2 degrees 2-theta. [0098] Firibastat: L-Proline crystal Form P2 as described in any aspect or embodiment of the present disclosure is obtainable by a process according to any of Example 8, Procedures A or B. The present disclosure therefore encompasses Firibastat crystal Form P2 is obtainable by a process according to any of Example 8, Procedures A or B.

[0099] In embodiments of the present disclosure, crystalline Form P2 of Firibastat: L-Proline is isolated. Particularly, crystalline Form P2 of Firibastat: L-proline according to any aspect or embodiment of the disclosure may be isolated.

[00100] Crystalline Form P2 of Firibastat: L-Proline may be polymorphically pure.

[00101] Crystalline Form P2 of Firibastat: L-Proline may be characterized by each of the above characteristics alone or by all possible combinations, e.g., an XRPD pattern having peaks at 12.9, 17.8, 20.2, 23.5 and 25.7 degrees 2-theta ± 0.2 degrees 2-theta; an XRPD pattern as depicted in Figure 7; and combinations thereof.

[00102] According to any aspect or embodiment of the present disclosure, the crystalline forms of Firibastat described herein (in particular Form A, Form B, Form El, and/or Form PI) may comprise: no more than about 10%, no more than about 5%, no more than about 2.5%, no more than about 2%, no more than about 1.5%, no more than about 1%, no more than about 0.5%, no more than about 0.25%, no more than about 0.2%, no more than about 0.1%, or no more than about 0.05%, by weight of residual solvent. In particular, Form A of Firibastat may comprise no more than about 2.5%, no more than about 2%, no more than about 1.5%, no more than about 1%, no more than about 0.5%, no more than about 0.25%, no more than about 0.2%, no more than about 0.1%, or no more than about 0.05%, by weight of residual solvent, wherein the residual solvent is preferably a C1-C6 alcohol and, particularly a C1-C3 alcohol, and more particularly ethanol. More preferably, Form A may comprise no more than about 2%, no more than about 1.5%, no more than about %, no more than about 0.5%, no more than about 0.25%, no more than about 0.2%, no more than about 0.1%, or no more than about 0.05% (e.g. about 0.2% to about 1.5%, or about 0.2% to about 1.0%, or about 0.2% to about 0.8%, or about 0.2% to about 0.5%), by weight of ethanol. In particular, Form B of Firibastat may comprise: no more than about 10%, no more than about 5%, no more than about 2.5%, no more about than 2%, no more than about 1.5%, no more than about 1%, no more than about 0.5%, no more than about 0.25%, no more than about 0.2%, no more than about 0.1%, or no more than about 0.05%, by weight of residual solvent, preferably wherein the residual solvent is an organic acid, particularly a C1-C6 carboxylic acid, a C2-C5 acid, and more preferably acetic acid or propionic acid. In particular, Form B may comprise no more than about 2.5%, no more than about 2%, no more than about 1.5%, no more than about 1%, no more than about 0.5%, no more than about 0.25%, no more than about 0.2%, no more than about 0.1%, or no more than about 0.05%, by weight of residual solvent, wherein the residual solvent is preferably a C1-C6 carboxylic acid, a C2-C5 acid, and more preferably acetic acid or propionic acid. More preferably, Form B may comprise no more than about 2%, no more than about 1.5%, no more than about 1%, no more than about 0.5%, no more than about 0.25%, no more than about 0.2%, no more than about 0.1%, or no more than about 0.05% (e.g. about 0.5% to about 2%, or about 0.5% to about 1.5%, or about 0.5% to about 1.2%), by weight of acetic acid, or Form B may comprise no more than 2%, no more than about 1.5%, no more than about 1%, no more than about 0.5%, no more than about 0.25%, no more than about 0.2%, no more than about 0.1%, or no more than about 0.05% (e.g. about 0.5% to about 2%, or about 0.5% to about 1.5%, about 0.5 to about 1.2%, or about 0.5% to about 1%) by weight of propionic acid.

[00103] According to any aspect or embodiment of the present disclosure, the crystalline forms of Firibastat described herein (in particular Form A and Form El), and Form PI may comprise: no more than about 40%, no more than about 35%, no more than about 30%, no more than about 25%, no more than about 20%, no more than about 15%, no more than about 10%, no more than about 5%, no more than about 2%, no more than about 1%, no more than about 0.5%, no more than about 0.25%, no more than about 0.2%, no more than about 0.1%, or no more than about 0.05% (e.g. about 0.1% to about 40%, about 0.1% to about 35%, about 0.1% to about 5%, about 0.1% to about 1.0%, or about 0.1 to about 0.5%), by weight of a strong acid or base, preferably wherein the strong acid is 1,2-ethanedi sulfonic acid, sulfuric acid, methanesulfonic acid, or p-toluenesulfonic acid, and preferably wherein the base is benzathine. In particular, Form A of Firibastat may comprise: no more than about 15%, no more than about 10%, no more than about 5%, no more than about 2%, no more than about 1%, no more than about 0.5%, no more than about 0.25%, no more than about 0.2%, no more than about 0.1%, or no more than about 0.05% (e.g. about 0% to about 10%, about 0.05% to about 5%, about 0.05% to about 2%, about 0.05% to about 1.0%, or about 0.05 to about 0.2%), by weight of 1,2-ethanedisulfonic acid, sulfuric acid, methanesulfonic acid, p-toluenesulfonic acid, or benzathine. More preferably, Form A may comprise no more than about 2%, no more than about 1.5%, no more than about 1%, no more than about 0.5%, no more than about 0.25%, no more than about 0.2%, no more than about 0.1%, or no more than about 0.05% % (e.g. about 0% to about 2%, about 0.05% to about 2%, about 0.05% to about 1.0%, or about 0.05 to about 0.2%), by weight of 1,2- ethanedisulfonic acid, sulfuric acid, methanesulfonic acid, or p-toluenesulfonic acid,; or Form A may comprise: no more than about 2%, no more than about 1.5%, no more than about 1%, no more than about 0.5%, no more than about 0.25%, no more than about 0.2%, no more than about 0.1%, or no more than about 0.05% % (e.g. about 0% to about 2%, about 0.05% to about 2%, about 0.05% to about 1.0%, or about 0.05 to about 0.2%), by weight of benzathine. In particular Form El may comprise: no more than about 40%, no more than about 35%, no more than about 30%, no more than about 25%, no more than about 20%, no more than about 15%, no more than about 10%, no more than about 5%, no more than about 2%, no more than about 1%, no more than about 0.5%, no more than about 0.25%, no more than about 0.2%, no more than about 0.1%, or no more than about 0.05% (e.g. about 0% to about 40%, about 0.1% to about 35%, about 0.5% to about 35%, about 1.0% to about 30%, about 1.0% to about 25%, about 1% to 20%, about 1% to about 10%, about 1% to about 5%, or about 1% to about 2%), by weight of a strong acid, preferably wherein the strong acid is 1,2-ethanedisulfonic acid, sulfuric acid, methanesulfonic acid, or p-toluenesulfonic acid, and more preferably 1,2-ethanedisulfonic acid, Form El may comprise: about 0% to about 40%, about 1% to about 35%, about 0.5% to about 35%, about 1% to about 30%, about 1% to about 25%, about 1% to about 20%, about 1% to about 10%, about 1% to about 5%, or about 1% to about 2% or about 0.1% to about 2%, or about 0.1% to about 1%), by weight of 1,2-ethanedisulfonic acid.

[00104] The above crystalline forms can be used to prepare other crystalline polymorphs of Firibastat, Firibastat salts or co-crystals and their solid state forms.

[00105] The present disclosure encompasses a process for preparing other solid state forms of Firibastat, Firibastat salts or co-crystals and solid state forms thereof. The process includes preparing any one or a mixture of the above disclosed form of Firibastat by the processes of the present disclosure, and converting it to said other form of Firibastat or Firibastat salt or co crystal.

[00106] The present disclosure includes a process for preparation of Form A of Firibastat wherein the process comprises crystallization of Firibastat in the presence of a strong acid, such as but not limited to: 1,2-ethanedisulfonic acid, sulfuric acid, methanesulfonic acid, p- toluenesulfonic acid in a solvent or a mixture of solvents wherein the acid is dissolved in the solvent or the mixture of solvents.

[00107] In embodiments, the process comprises: a) providing Firibastat, preferably in a hydrated form, in a solvent or mixture of solvents in the presence of a strong acid, preferably a strong acid such as but not limited to: 1,2- ethanedisulfonic acid, sulfuric acid, methanesulfonic acid, p-toluenesulfonic acid, wherein the is dissolved in the reaction mixture; b) optionally heating the reaction mixture; c) optionally cooling and optionally isolating Form A; d) optionally washing and/or drying Form A.

[00108] In one embodiment the reaction mixture in step (a) is performed a slurry. In embodiments step (a) is performed in a polar solvent which is capable of dissolving the acid, or in which the acid is miscible, preferably wherein the solvent is an alcohol (particularly a C1-C6 alcohol and more particularly a C1-C3 alcohol), more preferably ethanol. The strong acid is preferably used in an amount of: about 0.1 to about 4, about 0.2 to about 3.5, about 0.2 to about 3, or about 0.3 to about 3, or about 0.3 to about 2.7 equivalents relative to Firibastat. . The reaction mixture may optionally be heated to a temperature of from about 30 °C to about 50 °C.

In embodiments, in step (c) the solvent is separated by centrifuge.

[00109] The present disclosure includes a process for preparation of Form A wherein the process comprises crystallization of Firibastat in the presence of 1,2-ethanedisulfonic acid in a solvent or a mixture of solvents wherein 1,2-ethanedisulfonic acid is dissolved, or in the presence of Benzathine in a solvent or a mixture of solvents wherein benzathine is dissolved. The strong acid is preferably used in an amount of: about 0.1 to about 4, about 0.2 to about 3.5, about 0.2 to about 3, or about 0.3 to about 3, or about 0.3 to about 2.7 equivalents relative to equivalents relative to Firibastat. The benzathine is preferably used in an amount of: about 0.2 to about 3, about 0.4 to about 2.5, about 0.4 to about 2, or about 0.5 to about 1.5, or about 0.6 to about 1.4 equivalents relative to Firibastat.

[00110] In one embodiment, the process for preparing Form A comprises: a) providing Firibastat, preferably in a hydrated form, in a solvent or mixture of solvents in the presence of 1,2-ethanedisulfonic acid, wherein 1,2-ethanedisulfonic acid is dissolved in the reaction mixture; b) optionally heating the reaction mixture; c) optionally cooling and optionally isolating Form A; d) optionally washing and/or drying Form A.

[00111] In one embodiment the reaction mixture in step (a) is performed a slurry. In embodiments step (a) is performed in a polar solvent, which is capable of dissolving the 1,2- ethanedisulfonic acid preferably an alcohol (particularly a C1-C6 alcohol and more particularly a C ₁ -C ₃ alcohol), more preferably ethanol. The reaction mixture may optionally be heated to a temperature of from about 30 °C to about 50 °C. In embodiments, in step (c) the solvent is separated by centrifuge. The 1,2-ethanedisulfonic acid is preferably used in an amount of: about 0.1 to about 4, about 0.2 to about 3.5, about 0.2 to about 3, or about 0.3 to about 3, or about 0.3 to about 2.7 equivalents relative to Firibastat.

[00112] In another embodiment, the process for preparing Form A comprises: a) providing Firibastat, preferably in a hydrated form, in a solvent or mixture of solvents in the presence of benzathine, wherein benzathine is dissolved in the reaction mixture b) optionally heating the reaction mixture; c) optionally cooling and optionally isolating Form A; d) optionally washing and/or drying Form A.

[00113] In one embodiment the reaction mixture in step (a) is performed a slurry. In embodiments step (a) is performed in a polar solvent, which is capable of dissolving the benzathine preferably an alcohol (particularly a C ₁ -C ₆ alcohol and more particularly a C ₁ -C ₃ alcohol), more preferably ethanol. . The benzathine is preferably used in an amount of: about 0.2 to about 3, about 0.4 to about 2.5, about 0.4 to about 2, or about 0.5 to about 1.5, or about 0.6 to about 1.4 equivalents relative to Firibastat. The reaction mixture may optionally be heated to a temperature of from about 30 °C to about 50 °C. In embodiments, in step (c) the solvent is separated by centrifuge.

[00114] In another embodiment, the process for preparing Form A comprises: a) providing Firibastat, preferably in a hydrated form (preferably Form HI), in a solvent or mixture of solvents performed in a polar solvent, preferably alcohol (particularly a C1-C6 alcohol and more (particularly a C ₁ -C ₃ alcohol), more preferably ethanol) in the presence of an inorganic or organic acid (preferably a mineral acid or a carboxylic acid or a sulfonic acid, and more preferably sulfuric acid or methane sulfonic acid, or para-toluene sulfonic acid); b) optionally heating the reaction mixture; c) optionally cooling and optionally isolating Form A; and d) optionally washing and/or drying Form A.

[00115] In one embodiment the reaction mixture in step (a) is performed a slurry. In embodiments step (a) is performed in a polar solvent, preferably alcohol, (particularly a C1-C6 alcohol and more particularly a C1-C3 alcohol) more preferably ethanol. The acid is preferably used in an amount of: about 0.1 to about 4, about 0.2 to about 3.5, about 0.2 to about 3, or about 0.3 to about 3, or about 0.3 to about 2.7 equivalents relative to equivalents relative to Firibastat. The reaction mixture may optionally be heated to a temperature of from about 30 °C to about 50 °C. In embodiments, in step (c) the solvent is separated by centrifuge.

[00116] According to any aspect or embodiment of the process described herein for preparing Form A of Firibastat, the starting material may be any (preferably hydrated) form of Firibastat, such as Form HI or H2, or any mono-, di, or tri-hydrate form, including the trihydrate form disclosed in WO 2012/045849. According to any aspect or embodiment of the process for preparing Form A of Firibastat, after isolating the product, the solid may be dried, preferably under reduced pressure, and particularly at a temperature of: about 25°C to about 90°C; about 30°C to about 80°C; about 35°C to about 70°C, about 35°C to about 65°C or about 40°C to about 60°C.

[00117] According to any aspect or embodiment of the process for preparing Form A of Firibastat, the solvent is a polar solvent, and particularly a polar protic solvent, wherein the polar solvent is an alcohol, more particularly a C1-C6 alcohol and more particularly a C1-C3 alcohol), more preferably ethanol or isopropanol .

[00118] The present disclosure includes a process for preparation of Firibastat Form B wherein the process comprises: a) providing a slurry of Firibastat in a one or more solvents comprising an acid; b) optionally heating the reaction mixture; c) optionally cooling and optionally isolating Form B; and d) optionally washing and/or drying Form B.

[00119] In one embodiment, the sole solvent in step (a) is an acid, preferably an organic acid, particularly a C1-C6 carboxylic acid, a C2-C5 carboxylic acid, and more preferably acetic acid or propionic acid. Accordingly, the process for preparing Firibastat Form B comprise crystallising Firibastat from a solvent which is a C1-C6 carboxylic acid, a C2-C5 carboxylic acid, and more preferably acetic acid or propionic acid. The reaction mixture may optionally be heated to a temperature of from about 30 °C to about 60 °C. In embodiments, in step (c) the solvent is separated by centrifuge.

[00120] According to any aspect or embodiment of the process for preparing Form B of Firibastat, after isolating the product, the solid may be dried, preferably under reduced pressure, and particularly at a temperature of: about 25°C to about 90°C; about 30°C to about 80°C; about 35°C to about 70°C, about 35°C to about 65°C or about 40°C to about 60°C.

[00121] The present disclosure includes a process for preparation of Firibastat Form El wherein the process comprises: a) contacting Firibastat with 1,2-ethanedisulfonic acid wherein the molar ratio of Firibastat and 1,2-ethanedisulfonic acid is about 1:1 in the presence of one or more solvents wherein 1,2- ethanedisulfonic acid is not dissolved; b) ) optionally heating the reaction mixture; c) optionally cooling and optionally isolating Firibastat Form El; and d) optionally washing and/or drying Firibastat Form El.

[00122] In another aspect, the reaction mixture in step (a) is a slurry and preferably the Firibastat provided as starting material is a hydrated form or an anhydrous form. For example, the starting material in step (a) of the process for preparing Form El as described in any of the processes herein, may be any form of Firibastat, such as Form HI or H2, or any mono-, di, or tri hydrate form, including the trihydrate form disclosed in WO 2012/045849, or may be Form A as described herein. The 1,2-ethanedisulfonic acid may be used in an amount of: about 0.2 to about 2, about 0.5 to about 1.5, about 0.6 to about 1.2, about 0.8 to about 1.2, or about 0.9 to about 1.1, or about 1 mole equivalents relative to Firibastat.

[00123] According to any aspect or embodiment of the process for preparing Form El of Firibastat, after isolating the product, the solid may be dried, preferably under reduced pressure, and particularly at a temperature of: about 25°C to about 90°C; about 30°C to about 80°C; about 35°C to about 70°C, about 35°C to about 65°C or about 40°C to about 60°C.

[00124] I any aspect or embodiment of the process for preparing Form El, the 1,2- ethanesdisulfonic acid is used as a dihydrate. [00125] In embodiments, the solvent in step (a) is a polar aprotic solvent, preferably ether solvents, more preferably THF, halogenated solvents, more preferably dichloromethane, or ester solvents, more preferably ethyl acetate.

[00126] In embodiments the solvents in step (a) comprises one or more aromatic solvents such as toluene. Particularly, the reaction mixture in step (a) comprises a mixture of an aromatic solvent and an ester solvent, preferably a mixture of toluene and ethyl acetate. Preferably the ratio of ethyl acetate to toluene is from about 1 :6 to about 2:1, preferably from about 1 :4 to about 1:1, more preferably about 1:2.

[00127] The reaction mixture may optionally be heated to a temperature of from about 30 °C to about 50 °C. In embodiments, in step (c) the solvent is separated by centrifuge.

[00128] The present disclosure further provides a process for the preparation of Firibastat: piperazine, preferably Form PI, comprising:

(i) contacting Firibastat with piperazine wherein the molar ratio of Firibastat and piperazine is from about 1 :0.5 to about 1 :5 in the presence of one or more solvents;

(ii) optionally removing the solvents;

(iii) optionally isolating Firibastafpiperazine; and

(iv) optionally drying Firibastat: piperazine.

[00129] In one aspect the reaction mixture in step (i) is a solution. In embodiments step (i) comprises contacting Firibastat and piperazine in water or in a mixture of solvents comprising water and step (ii) comprises removing the solvent or solvent mixture.

[00130] In another aspect, the reaction mixture in step (i) is a slurry and preferably the Firibastat provided as starting material is a hydrated form. In embodiments, the solvent is a polar solvent, preferably an alcohol, more preferably isopropanol. The reaction mixture may optionally be heated to a temperature of from about 30 °C to about 50 °C. In embodiments, in step (ii) the solvent is separated by centrifuge.

[00131] According to any aspect or embodiment of the process for preparing Form PI of Firibastat, after isolating the product, the solid may be dried, preferably under reduced pressure, and particularly at a temperature of: about 25°C to about 90°C; about 30°C to about 80°C; about 35°C to about 70°C, about 35°C to about 65°C, or about 40°C to about 60°C.

[00132] The present disclosure further provides a process for the preparation of a Firibastat: L-Proline, preferably Form P2, comprising: (i) contacting Firibastat with L-Proline in the presence of one or more solvents;

(ii) optionally removing the solvents;

(iii) optionally isolating Firibastat: L-Proline; and

(iv) optionally drying Firibastat: L-Proline.

[00133] In one aspect the reaction mixture in step (i) is a solution. In embodiments step (i) comprises contacting Firibastat and L-Proline in one or more polar solvents and step (ii) comprises removing the solvent or solvent mixture.

[00134] In another aspect, the reaction mixture in step (i) is a slurry. In embodiments the Firibastat provided as starting material is a non-hydrated form. In embodiments, the solvent is a polar solvent, preferably an alcohol, more preferably isopropanol. The reaction mixture may optionally be heated to a temperature of from about 30 °C to about 50 °C. In embodiments, in step (ii) the solvent is separated by centrifuge.

[00135] According to any aspect or embodiment of the process for preparing Form P2 of Firibastat, after isolating the product, the solid may be dried, preferably under reduced pressure, and particularly at a temperature of: about 25°C to about 90°C; about 30°C to about 80°C; about 35°C to about 85°C, about 35°C to about 80°C or about 40°C to about 75°C.

[00136] In embodiments, the molar ratio of Firibastat to L-Proline is from about 1 :4 to about 4:1, or from about 1:3 to about 3:1, or from about 1:2.5 to about 2.5:1. In embodiments the molar ratio of Firibastat to L-Proline is about 1 :2.

[00137] The present disclosure further relates to a product obtainable by any of the processes described herein.

[00138] Any of the above described processes may further comprise a step of combining the crystalline product with at least one pharmaceutically acceptable excipient to provide a pharmaceutical composition.

[00139] The present disclosure provides the above described crystalline polymorphs of Firibastat, Firibastat salts or co-crystals for use in the preparation of pharmaceutical compositions comprising Firibastat, Firibastat salts or co-crystals and/or crystalline polymorphs thereof.

[00140] The present disclosure also encompasses the use of crystalline polymorphs of Firibastat, Firibastat salts or co-crystals of the present disclosure for the preparation of pharmaceutical compositions of crystalline polymorph Firibastat, Firibastat salts or co-crystals and/or crystalline polymorphs thereof.

[00141] The present disclosure includes processes for preparing the above mentioned pharmaceutical compositions. The processes include combining any one or a combination of the crystalline polymorphs of Firibastat, Firibastat salts or co-crystals of the present disclosure with at least one pharmaceutically acceptable excipient.

[00142] Pharmaceutical combinations or formulations of the present disclosure contain any one or a combination of the solid state forms of Firibastat, Firibastat salts or co-crystals of the present disclosure. In addition to the active ingredient, the pharmaceutical formulations of the present disclosure can contain one or more excipients. Excipients are added to the formulation for a variety of purposes.

[00143] Diluents increase the bulk of a solid pharmaceutical composition, and can make a pharmaceutical dosage form containing the composition easier for the patient and caregiver to handle. Diluents for solid compositions include, for example, microcrystalline cellulose (e.g., Avicel®), microfme cellulose, lactose, starch, pregelatinized starch, calcium carbonate, calcium sulfate, sugar, dextrates, dextrin, dextrose, dibasic calcium phosphate dihydrate, tribasic calcium phosphate, kaolin, magnesium carbonate, magnesium oxide, maltodextrin, mannitol, polymethacrylates (e.g., Eudragit®), potassium chloride, powdered cellulose, sodium chloride, sorbitol, and talc.

[00144] Solid pharmaceutical compositions that are compacted into a dosage form, such as a tablet, can include excipients whose functions include helping to bind the active ingredient and other excipients together after compression. Binders for solid pharmaceutical compositions include acacia, alginic acid, carbomer (e.g. carbopol), carboxymethylcellulose sodium, dextrin, ethyl cellulose, gelatin, guar gum, hydrogenated vegetable oil, hydroxyethyl cellulose, hydroxypropyl cellulose (e.g. Klucel®), hydroxypropyl methyl cellulose (e.g. Methocel®), liquid glucose, magnesium aluminum silicate, maltodextrin, methylcellulose, polymethacrylates, povidone (e.g. Kollidon®, Plasdone®), pregelatinized starch, sodium alginate, and starch. [00145] The dissolution rate of a compacted solid pharmaceutical composition in the patient's stomach can be increased by the addition of a disintegrant to the composition. Disintegrants include alginic acid, carboxymethylcellulose calcium, carboxymethylcellulose sodium (e.g., Ac- Di-Sol®, Primellose®), colloidal silicon dioxide, croscarmellose sodium, crospovidone (e.g., Kollidon®, Polyplasdone®), guar gum, magnesium aluminum silicate, methyl cellulose, microcrystalline cellulose, polacrilin potassium, powdered cellulose, pregelatinized starch, sodium alginate, sodium starch glycolate (e.g., Explotab®), and starch.

[00146] Glidants can be added to improve the flowability of a non-compacted solid composition and to improve the accuracy of dosing. Excipients that can function as glidants include colloidal silicon dioxide, magnesium trisilicate, powdered cellulose, starch, talc, and tribasic calcium phosphate.

[00147] When a dosage form such as a tablet is made by the compaction of a powdered composition, the composition is subjected to pressure from a punch and dye. Some excipients and active ingredients have a tendency to adhere to the surfaces of the punch and dye, which can cause the product to have pitting and other surface irregularities. A lubricant can be added to the composition to reduce adhesion and ease the release of the product from the dye. Lubricants include magnesium stearate, calcium stearate, glyceryl monostearate, glyceryl palmitostearate, hydrogenated castor oil, hydrogenated vegetable oil, mineral oil, polyethylene glycol, sodium benzoate, sodium lauryl sulfate, sodium stearyl fumarate, stearic acid, talc, and zinc stearate. [00148] Flavoring agents and flavor enhancers make the dosage form more palatable to the patient. Common flavoring agents and flavor enhancers for pharmaceutical products that can be included in the composition of the present disclosure include maltol, vanillin, ethyl vanillin, menthol, citric acid, fumaric acid, ethyl maltol, and tartaric acid.

[00149] Solid and liquid compositions can also be dyed using any pharmaceutically acceptable colorant to improve their appearance and/or facilitate patient identification of the product and unit dosage level.

[00150] In liquid pharmaceutical compositions of the present invention, Firibastat, Firibastat salts or co-crystals and any other solid excipients can be dissolved or suspended in a liquid carrier such as water, vegetable oil, alcohol, polyethylene glycol, propylene glycol, or glycerin. [00151] Liquid pharmaceutical compositions can contain emulsifying agents to disperse uniformly throughout the composition an active ingredient or other excipient that is not soluble in the liquid carrier. Emulsifying agents that can be useful in liquid compositions of the present invention include, for example, gelatin, egg yolk, casein, cholesterol, acacia, tragacanth, chondrus, pectin, methyl cellulose, carbomer, cetostearyl alcohol, and cetyl alcohol. [00152] Liquid pharmaceutical compositions of the present invention can also contain a viscosity enhancing agent to improve the mouth-feel of the product and/or coat the lining of the gastrointestinal tract. Such agents include acacia, alginic acid bentonite, carbomer, carboxymethylcellulose calcium or sodium, cetostearyl alcohol, methyl cellulose, ethylcellulose, gelatin guar gum, hydroxyethyl cellulose, hydroxypropyl cellulose, hydroxypropyl methyl cellulose, maltodextrin, polyvinyl alcohol, povidone, propylene carbonate, propylene glycol alginate, sodium alginate, sodium starch glycolate, starch tragacanth, xanthan gum and combinations thereof.

[00153] Sweetening agents such as sorbitol, saccharin, sodium saccharin, sucrose, aspartame, fructose, mannitol, and invert sugar can be added to improve the taste.

[00154] Preservatives and chelating agents such as alcohol, sodium benzoate, butylated hydroxyl toluene, butylated hydroxyanisole, and ethylenediamine tetraacetic acid can be added at levels safe for ingestion to improve storage stability.

[00155] According to the present disclosure, a liquid composition can also contain a buffer such as gluconic acid, lactic acid, citric acid, or acetic acid, sodium gluconate, sodium lactate, sodium citrate, or sodium acetate. Selection of excipients and the amounts used can be readily determined by the formulation scientist based upon experience and consideration of standard procedures and reference works in the field.

[00156] The solid compositions of the present disclosure include powders, granulates, aggregates, and compacted compositions. The dosages include dosages suitable for oral, buccal, rectal, parenteral (including subcutaneous, intramuscular, and intravenous), inhalant, and ophthalmic administration. Although the most suitable administration in any given case will depend on the nature and severity of the condition being treated, in embodiments the route of administration is oral. The dosages can be conveniently presented in unit dosage form and prepared by any of the methods well-known in the pharmaceutical arts.

[00157] Dosage forms include solid dosage forms like tablets, powders, capsules, suppositories, sachets, troches, and lozenges, as well as liquid syrups, suspensions, and elixirs. [00158] The dosage form of the present disclosure can be a capsule containing the composition, such as a powdered or granulated solid composition of the disclosure, within either a hard or soft shell. The shell can be made from gelatin and optionally contain a plasticizer such as glycerin and/or sorbitol, an opacifying agent and/or colorant. [00159] The active ingredient and excipients can be formulated into compositions and dosage forms according to methods known in the art.

[00160] A composition for tableting or capsule filling can be prepared by wet granulation. In wet granulation, some or all of the active ingredients and excipients in powder form are blended and then further mixed in the presence of a liquid, typically water, that causes the powders to clump into granules. The granulate is screened and/or milled, dried, and then screened and/or milled to the desired particle size. The granulate can then be tableted, or other excipients can be added prior to tableting, such as a glidant and/or a lubricant.

[00161] A tableting composition can be prepared conventionally by dry blending. For example, the blended composition of the actives and excipients can be compacted into a slug or a sheet and then comminuted into compacted granules. The compacted granules can subsequently be compressed into a tablet.

[00162] As an alternative to dry granulation, a blended composition can be compressed directly into a compacted dosage form using direct compression techniques. Direct compression produces a more uniform tablet without granules. Excipients that are particularly well suited for direct compression tableting include microcrystalline cellulose, spray dried lactose, dicalcium phosphate dihydrate, and colloidal silica. The proper use of these and other excipients in direct compression tableting is known to those in the art with experience and skill in particular formulation challenges of direct compression tableting.

[00163] A capsule filling of the present disclosure can include any of the aforementioned blends and granulates that were described with reference to tableting, but they are not subjected to a final tableting step.

[00164] A pharmaceutical formulation of Firibastat, Firibastat salts or co-crystals can be administered. Firibastat, Firibastat salts or co-crystals may be formulated for administration to a mammal, in embodiments to a human, by injection. Firibastat, Firibastat salts or co-crystals can be formulated, for example, as a viscous liquid solution or suspension, such as a clear solution, for injection. The formulation can contain one or more solvents. A suitable solvent can be selected by considering the solvent's physical and chemical stability at various pH levels, viscosity (which would allow for syringeability), fluidity, boiling point, miscibility, and purity. Suitable solvents include alcohol USP, benzyl alcohol NF, benzyl benzoate USP, and Castor oil USP. Additional substances can be added to the formulation such as buffers, solubilizers, and antioxidants, among others. Ansel et al., Pharmaceutical Dosage Forms and Drug Delivery Systems, 7th ed.

[00165] The crystalline polymorphs of Firibastat, Firibastat salts or co-crystals and the pharmaceutical compositions and/or formulations of Firibastat, Firibastat salts or co-crystals of the present disclosure can be used as medicaments, in embodiments in the treatment of hypertension.

[00166] The present disclosure also provides methods of treating hypertension by administering a therapeutically effective amount of any one or a combination of the crystalline polymorphs of Firibastat, Firibastat salts or co-crystals of the present disclosure, or at least one of the above pharmaceutical compositions and/or formulations, to a subject in need of the treatment.

[00167] Having thus described the disclosure with reference to particular preferred embodiments and illustrative examples, those in the art can appreciate modifications to the disclosure as described and illustrated that do not depart from the spirit and scope of the disclosure as disclosed in the specification. The Examples are set forth to aid in understanding the disclosure but are not intended to, and should not be construed to limit its scope in any way. [00168] Further aspects and embodiments of the present disclosure are set out in the numbered clauses below:

Al. A crystalline form, designated Form A, which is characterized by data selected from one or more of the following: a. an XRPD pattern having peaks at 11.2, 16.3, 17.8, 19.9 and 23.4 degrees 2-theta ± 0.2 degrees 2-theta; b. an XRPD pattern as depicted in Figure 3; c. a solid state ¹³ C NMR spectrum having characteristic peaks at 49.9, 49.0, 46.3, 42.9, 39.5, 31.0 and 26.9 ppm ± 0.2 ppm; d. a solid state ¹³ C NMR spectrum substantially as depicted in Figure 8 or in Figure 8A; and e. combination of these data.

A2. A crystalline product according to Clause Al, designated Form A, characterized by the XRPD pattern having peaks at 11.2, 16.3, 17.8, 19.9 and 23.4 degrees 2-theta ± 0.2 degrees 2- theta, and also having one, two, three or four additional peaks selected from 18.8, 21.7, 22.3,

26.6 and 27.2 degrees two theta ± 0.2 degrees two theta.

A3. A crystalline form, designated Form A, according to any one of Clauses A1 or A2 wherein the form is anhydrous.

A4. A crystalline product according to any one of Clauses A1-A3 designated Form A which contains: no more than about 20%, no more than about 10%, no more than about 5%, no more than about 2%, no more than about 1% or about 0% of any other crystalline forms of Firibastat.

A5. A crystalline product according to any one of Clauses A1-A3, or A4, designated Form A, which contains: no more than about 20%, no more than about 10%, no more than about 5%, no more than about 2%, no more than about 1% or about 0% of amorphous Firibastat.

A6. A process for preparation of Form A, according to any one of clauses A1-A5, wherein the process comprises crystallization of Firibastat in the presence of 1,2-ethanedisulfonic acid in a solvent or a mixture of solvents wherein 1,2-ethanedisulfonic acid is dissolved, or in the presence of Benzathine in a solvent or a mixture of solvents wherein benzathine is dissolved.

A7. A process according to clause A6 wherein the process comprises: a) providing Firibastat, preferably in a hydrated form, in a solvent or mixture of solvents in the presence of 1,2-ethanedisulfonic acid, wherein 1,2-ethanedisulfonic acid is dissolved in the reaction mixture; b) optionally heating the reaction mixture; c) optionally cooling and optionally isolating Form A; and d) optionally washing and/or drying Form A.

A8. A process for preparation of Form A, according to any one of clauses A1-A5, wherein the process comprises crystallization of Firibastat in the presence of a strong acid, such as, but not limited to: 1,2-ethanedisulfonic acid, sulfuric acid, methanesulfonic acid, p-toluenesulfonic acid in a solvent or a mixture of solvents wherein the acid is dissolved in the solvent or the mixture of solvents.

A9. A process according to clause A8 wherein the process comprises: a) providing Firibastat, in a solvent or mixture of solvents in the presence of a strong acid, preferably a strong acid such as but not limited to: 1,2-ethanedisulfonic acid, sulfuric acid, methanesulfonic acid, p-toluenesulfonic acid, wherein the acid is dissolved in the reaction mixture; b) optionally heating the reaction mixture; c) optionally cooling and optionally isolating Form A; and d) optionally washing and/or drying Form A.

A10. A process according to clause A8 wherein the process comprises: a) providing Firibastat, preferably in a hydrated form in a solvent or mixture of solvents performed in the presence of an inorganic or organic acid (preferably a mineral acid or a carboxylic acid or a sulfonic acid, and more preferably sulfuric acid or methane sulfonic acid or para-toluene sulfonic acid, wherein the acid is dissolved in the reaction mixture; b) optionally heating the reaction mixture; c) optionally cooling and optionally isolating Form A; and d) optionally washing and/or drying Form A.

A11. A process according to Clause A7, A9 or A10 wherein the reaction mixture is step (a) is a slurry.

A12. A process according to any one of Clauses A7-A11 wherein step (a) is performed in a polar solvent which is capable of dissolving the acid, or in which the acid is miscible, preferably alcohol, particularly a C1-C6 alcohol and more particularly a C1-C3 alcohol, more preferably ethanol.

A13. A process according to any one of clauses A7-A12 wherein the strong acid is preferably used in an amount of: about 0.1 to about 4, about 0.2 to about 3.5, about 0.2 to about 3, or about 0.3 to about 3, or about 0.3 to about 2.7 equivalents relative to Firibastat

A14. A process according to any one of Clauses A7-A13 wherein the reaction mixture is heated to temperature of from about 30 °C to about 50 °C.

A15. A process according to any one of Clauses A7-A14 wherein in step (c) the solvent is separated by centrifuge. A16. A process according to clause A6 wherein the process comprises: a) providing Firibastat, preferably in a hydrated form, in a solvent or mixture of solvents in the presence of benzathine, wherein benzathine is dissolved in the reaction mixture; b) optionally heating the reaction mixture; c) optionally cooling and optionally isolating Form A; and d) optionally washing and/or drying Form A.

A17. A process according to Clause A16 wherein the reaction mixture is step (a) is a slurry.

A18. A process according to any one of Clauses A16-A17 wherein step (a) is performed in a polar solvent, which is capable of dissolving benzathine, or in which benzathine is miscible, preferably alcohol, (particularly a C1-C6 alcohol and more particularly a C1-C3 alcohol)more preferably ethanol.

A19. A process according to any one of clauses A16-A18 wherein benzathine is preferably used in an amount of: about 0.2 to about 3, about 0.4 to about 2.5, about 0.4 to about 2, or about 0.5 to about 1.5, or about 0.6 to about 1.4 equivalents relative to Firibastat

A20. A process according to any one of Clauses A16-A19 wherein the reaction mixture is heated to temperature of from about 30 °C to about 50 °C.

A21. A process according to any one of Clauses A16-A20 wherein in step (c) the solvent is separated by centrifuge.

A22. A process according to any one of Clauses A6-A21 further comprising combining the crystalline product with at least one pharmaceutically acceptable excipient to provide a pharmaceutical composition.

A23. A crystalline product obtainable by a process according to any one of Claims A6-A20.

A24. A pharmaceutical composition comprising a crystalline product according to any of Clauses A1-A5 or A23, and at least one pharmaceutically acceptable excipient.

A25. Use of a crystalline product according to any of Clauses A1-A5 or A23 for the preparation of a pharmaceutical composition and/or formulation. A26. A process for preparing the pharmaceutical composition according to Clause A24, comprising combining a crystalline product according to any of Clauses A1-A5 or A23 with at least one pharmaceutically acceptable excipient.

A27. A crystalline product according to any of Clauses A1-A5 or A23, or a pharmaceutical composition according to Clause A24, for use as a medicament.

A28. A crystalline product according to any of Clauses A1-A5 or A23, or a pharmaceutical composition according to Clause A19, for use in the treatment of hypertension

A29. A method of treating hypertension comprising administering a therapeutically effective amount of a crystalline product according to any of Clauses A1-A5 or A23, or a pharmaceutical composition according to Clause A24, to a subject in need of the treatment.

A30. Use of a crystalline product according to any of Clauses A1-A5 or A23, in the preparation of another solid state form of Firibastat or Firibastat salt

A31. A process for preparing a solid state form of Firibastat or Firibastat salt comprising preparing any one or a combination of a crystalline product according to any one of Clauses Al- A5 or A23, and converting it to another a solid state form thereof or Firibastat salt.

Bl. A crystalline form, designated Form B, which is characterized by data selected from one or more of the following: a. an XRPD pattern having peaks at 9.4, 13.3, 18.5, 20.1 and 23.3 degrees 2-theta ± 0.2 degrees 2-theta; b. an XRPD pattern as depicted in Figure 4; and c. combination of these data.

B2. A crystalline product according to Clause Bl, designated Form B, characterized by the XRPD pattern having peaks at 9.4, 13.3, 18.5, 20.1 and 23.3 degrees 2-theta ± 0.2 degrees 2- theta, and also having one, two, three or four additional peaks selected from 17.6, 17.9, 22.3,

24. land 25.5 degrees two theta ± 0.2 degrees two theta.

B3. A crystalline product according to any one of Clauses B1-B2 designated Form B which contains: no more than about 20%, no more than about 10%, no more than about 5%, no more than about 2%, no more than about 1% or about 0% of any other crystalline forms of Firibastat. B4. A crystalline product according to any one of Clauses B1-B2, or B3, designated Form B, which contains: no more than about 20%, no more than about 10%, no more than about 5%, no more than about 2%, no more than about 1% or about 0% of amorphous Firibastat.

B5. A process for preparation of Form B according to any one of clauses B1-B4 wherein the process comprises: a) providing a slurry of Firibastat in a one or more solvents comprising an acid; b) optionally heating the reaction mixture; c) optionally cooling and optionally isolating Form B; and d) optionally washing and/or drying Form B.

B6. A process according to Clause B5 wherein the sole solvent in step (a) is an acid, preferably an organic acid, particularly a C1-C6 carboxylic acid, a C2-C5 acid, and more preferably acetic acid or propionic acid.

B7. A process according to any one of clauses B5-B6 wherein the reaction mixture is heated to a temperature of from about 30 °C to about 60 °C.

B8. A process according to any one of clauses B5-B7 wherein in step (c) the solvent is separated by centrifuge.

B9. A process according to any one of Clauses B5-B8 further comprising combining the crystalline product with at least one pharmaceutically acceptable excipient to provide a pharmaceutical composition.

B10. A crystalline product obtainable by a process according to any one of Claims B5-B8.

B11. A pharmaceutical composition comprising a crystalline product according to any of Clauses B1-B4 or B10, and at least one pharmaceutically acceptable excipient.

B12. Use of a crystalline product according to any of Clauses B1-B4 or B10 for the preparation of a pharmaceutical composition and/or formulation.

B13. A process for preparing the pharmaceutical composition according to Clause B11, comprising combining a crystalline product according to any of Clauses B1-B4 or B10 with at least one pharmaceutically acceptable excipient. B14. A crystalline product according to any of Clauses B1-B4 or BIO, or a pharmaceutical composition according to Clause B 12, for use as a medicament.

B15. A crystalline product according to any of Claims B1-B4 or BIO, or a pharmaceutical composition according to Claim B11, for use in the treatment of hypertension.

B16. A method of treating hypertension comprising administering a therapeutically effective amount of a crystalline product according to any of Clauses B1-B4 or BIO, or a pharmaceutical composition according to Clause B11, to a subject in need of the treatment.

B17. Use of a crystalline product according to any of Clauses B1-B4 or BIO, in the preparation of another solid state form of Firibastat or Firibastat salt.

B18. A process for preparing a solid state form of Firibastat or Firibastat salt comprising preparing any one or a combination of a crystalline product according to any one of Clauses Bl- B4 or BIO, and converting it to another a solid state form thereof or Firibastat salt.

Cl. Crystalline Firibastat: piperazine.

C2. Crystalline Firibastat: piperazine which is a co-crystal.

C3. Crystalline Firibastat: piperazinium which is a salt (i.e. Firibastat piperazine salt), optionally wherein the ratio of Firibastat to piperazine is about 1: 1.5 to about 1.5: 1, preferably between about 1: 1.25 and about 1.25: 1, about 1:2 or about 1:1, and preferably about 1:2.

C4. A crystalline product according to any one of Clauses C1-C3, designated Form PI, which is characterized by data selected from one or more of the following: a. an XRPD pattern having peaks at 12.5, 16.4, 17.6, 19.5 and 22.1 degrees 2-theta ±

0.2 degrees 2-theta; b. an XRPD pattern as depicted in Figure 6; and c. combinations of these data.

C5. A crystalline product according to any one of Clauses C1-C4, designated Form PI, characterized by the XRPD pattern having peaks at 12.5, 16.4, 17.6, 19.5 and 22.1 degrees 2- theta ± 0.2 degrees 2-theta, and also having one, two, three or four additional peaks selected from 15.7, 20.0, 20.7, 25.1 and 27.7 degrees two theta ± 0.2 degrees two theta. C6. A crystalline product according to any one of Clauses C1-C5, designated Form PI which contains: no more than about 20%, no more than about 10%, no more than about 5%, no more than about 2%, no more than about 1% or about 0% of any other crystalline forms of Firibastat: piperazine.

C7. A crystalline product according to any one of Clauses C1-C5, or C6, designated Form PI, which contains: no more than about 20%, no more than about 10%, no more than about 5%, no more than about 2%, no more than about 1% or about 0% of amorphous Firibastat: piperazine.

C8. A process for the preparation of a crystalline product according to any one of Clauses C1-C7 comprising:

(i) contacting Firibastat or a salt thereof with piperazine wherein the molar ratio of Firibastat and piperazine is from about 1 :0.5 to about 1 :5 in the presence of one or more solvents;

(ii) optionally removing the solvents;

(iii) optionally isolating Firibastat: piperazine; and

(iv) optionally drying Firibastat: piperazine.

C9. A process according to clause C8 wherein the reaction mixture in step (i) is a solution.

CIO. A process according to Clause C8 or clause C9 wherein step (i) comprises contacting Firibastat and piperazine in water or in a mixture of solvents comprising water and step (ii) comprises removing the solvent or solvent mixture.

Cl 1. A process according to Clause C8 wherein the reaction mixture in step (i) is a slurry.

C12. A process according to Clauses C8 or Cl 1, wherein the Firibastat provided as starting material is in a hydrated form.

C13. A process according to any of Clauses C8, Cl 1 or C12, wherein the solvent is a polar solvent, preferably an alcohol, more preferably isopropanol.

C14. A process according to any one of clauses C8, Cl 1, C12 or C13 wherein the reaction mixture is optionally heated to a temperature of about 30 °C to about 50 °C.

C15. A process according to any one of clauses C8, Cl 1, C12, C13 or C14 wherein in step (ii) the solvent is separated by centrifuge.

Cl 6. A process according to any one of Clauses C8-C15 further comprising combining the crystalline product with at least one pharmaceutically acceptable excipient to provide a pharmaceutical composition.

Cl 7. A crystalline product obtainable by a process according to any one of Claims C8-C15.

C18. A pharmaceutical composition comprising a crystalline product according to any of Clauses C1-C7 or Cl 7, and at least one pharmaceutically acceptable excipient.

C19. Use of a crystalline product according to any of Clauses C1-C7 or C17 for the preparation of a pharmaceutical composition and/or formulation.

C20. A process for preparing the pharmaceutical composition according to Clause Cl 8, comprising combining a crystalline product according to any of Clauses C1-C7 or C17 with at least one pharmaceutically acceptable excipient.

C21. A crystalline product according to any of Clauses C1-C7 or Cl 7, or a pharmaceutical composition according to Clause Cl 8, for use as a medicament.

C22. A crystalline product according to any of Claims C1-C7 or Cl 7, or a pharmaceutical composition according to Claim Cl 8, for use in the treatment of hypertension

C23. A method of treating hypertension comprising administering a therapeutically effective amount of a crystalline product according to any of Clauses C1-C7 or Cl 7, or a pharmaceutical composition according to Clause Cl 8, to a subject in need of the treatment.

C24. Use of a crystalline product according to any of Clauses C1-C7 or Cl 7, in the preparation of another solid state form of Firibastat: piperazine or Firibastat salt.

C25. A process for preparing a solid state form of Firibastat: piperazine or Firibastat salt comprising preparing any one or a combination of a crystalline product according to any one of Clauses C1-C7 or Cl 7, and converting it to another a solid state form thereof or Firibastat salt.

Dl. A crystalline Firibastat designated Form El, which is characterized by data selected from one or more of the following: a. an XRPD pattern having peaks at 11.8, 18.1, 20.6, 21.3 and 24.6 degrees 2- theta ± 0.2 degrees 2-theta; b. an XRPD pattern as depicted in Figure 5; c. a solid state ¹³ C NMR spectrum having characteristic peaks at 29.4, 37.9, 44.9, 47.0, and 50.3 ppm ± 0.2 ppm; d. a solid state ¹³ C NMR spectrum substantially as depicted in Figure 9 or in Figure 9A; and e. combinations of these data.

D2. A crystalline product according to Clause Dl, designated Form El, characterized by the XRPD pattern having peaks at 11.8, 18.1, 20.6, 21.3 and 24.6 degrees 2-theta ± 0.2 degrees 2- theta, and also having one, two, three or four additional peaks selected from 22.3, 22.9, 23.3, 23.7 and 27.3 degrees two theta ± 0.2 degrees two theta.

D3. A crystalline form, designated Form El, according to any one of Clauses Dl or D2 wherein the form is a hydrate.

D4. A crystalline product according to any of Clauses D1-D3, designated Form El which contains: no more than about 20%, no more than about 10%, no more than about 5%, no more than about 2%, no more than about 1% or about 0% of any other crystalline forms of Firibastat

D5. A crystalline product according to any of Clauses D1-D3 or D4, designated Form El, which contains: no more than about 20%, no more than about 10%, no more than about 5%, no more than about 2%, no more than about 1% or about 0% of amorphous Firibastat

D6. A process for the preparation of a crystalline product according to any of Clauses D1-D5, comprising:

(a) contacting Firibastat with 1,2-ethanedisulfonic acid wherein the molar ratio of Firibastat and 1,2-ethanedisulfonic acid is about 1:1 in the presence of one or more solvents wherein 1,2-ethanedisulfonic acid is not dissolved;

(b) optionally heating the reaction mixture;

(c) optionally cooling and optionally isolating Firibastat Form El; and

(d) optionally washing and/or drying Firibastat Form El .

D7. A process according to clause D6 wherein the reaction mixture in step (a) is a slurry. D8. A process according to any one of Clause D6 or clause D7 wherein the Firibastat provided as starting material is in a hydrated form.

D9. A process according to any one of Clauses D6-D8 wherein the solvent comprises one or more polar aprotic solvents, preferably ether solvents, more preferably THF, halogenated solvents, more preferably dichloromethane or ester solvents, more preferably ethyl acetate.

DIO. A process according to any one of Clauses D6-D8 wherein the solvent comprises one or more aromatic solvents, preferably toluene.

D11. A process according to any one of Clauses D6-D10 wherein the reaction mixture is optionally heated to a temperature of about 30 °C to about 50 °C.

D12. A process according to any one of Clauses D6-D11 wherein in step (c) the solvent is separated by centrifuge.

D13. A process according to any of Clauses D6-D12 further comprising combining the crystalline product with at least one pharmaceutically acceptable excipient to provide a pharmaceutical composition.

D14. A crystalline product obtainable by a process according to any of Clauses D6-D12.

D15. A pharmaceutical composition comprising a crystalline product according to any of Clauses D1-D5 or D14, and at least one pharmaceutically acceptable excipient.

D16. Use of a crystalline product according to any of Clauses D1-D5 or D14 for the preparation of a pharmaceutical composition and/or formulation.

D17. A process for preparing the pharmaceutical composition according to Clause D15, comprising combining a crystalline product according to any of Clauses D1-D5 or D14 with at least one pharmaceutically acceptable excipient.

D18. A crystalline product according to any of Clauses D1-D5 or D 14, or a pharmaceutical composition according to Clause D17, for use as a medicament.

D19. A crystalline product according to any of Claims D1-D5 or D14, or a pharmaceutical composition according to Clause D 15, for use in the treatment of hypertension

D20. A method of treating hypertension comprising administering a therapeutically effective amount of a crystalline product according to any of Clauses D1-D5 or D 14, or a pharmaceutical composition according to Clause D 15, to a subject in need of the treatment.

D21. Use of a crystalline product according to any of Clauses D1-D5 or D14, in the preparation of another solid state form of Firibastat or Firibastat salt.

D22. A process for preparing a solid state form of Firibastat or Firibastat salt comprising preparing any one or a combination of a crystalline product according to any one of Clauses Dl- D5 or D14, and converting it to another a solid state form thereof or Firibastat salt.

El. Crystalline Firibastat: L-Proline.

E2. Crystalline Firibastat: L-Proline which is a co-crystal.

E3. Crystalline Firibastat: L-Proline which is a salt.

E4. A crystalline product according to any one of Clauses E1-E3, designated Form P2, which is characterized by data selected from one or more of the following:

(i) an XRPD pattern having peaks at 12.9, 17.8, 20.2, 23.5 and 25.7 degrees 2-theta ± 0.2 degrees 2-theta;

(ii) an XRPD pattern as depicted in Figure 7; and

(iii) combinations of these data.

E5. A crystalline product according to any one of Clauses E1-E4, designated Form P2, characterized by the XRPD pattern having peaks at 12.9, 17.8, 20.2, 23.5 and 25.7 degrees 2- theta ± 0.2 degrees 2-theta, and also having one, two, three or four additional peaks selected from 18.5, 19.0, 19.7, 21.3 and 21.9 degrees two theta ± 0.2 degrees two theta.

E6. A crystalline product according to any one of Clauses E1-E5, designated Form P2 which contains: no more than about 20%, no more than about 10%, no more than about 5%, no more than about 2%, no more than about 1% or about 0% of any other crystalline forms of Firibastat.

E7. A crystalline product according to any one of Clauses E1-E5 , or E6, designated Form P2, which contains: no more than about 20%, no more than about 10%, no more than about 5%, no more than about 2%, no more than about 1% or about 0% of amorphous Firibastat.

E8. A process for the preparation of a crystalline product according to any one of Clauses E1-E7 comprising:

(i) contacting Firibastat or a salt thereof with L-Proline in the presence of one or more solvents;

(ii) optionally removing the solvents;

(iii) optionally isolating Firibastat: L-Proline; and

(iv) optionally drying Firibastat: L-Proline.

E9. A process according to clause E8 wherein the reaction mixture in step (i) is a solution.

E10. A process according to Clause E8 or clause E9 wherein step (i) comprises contacting Firibastat and L-Proline in one or more Polar solvents and step (ii) comprises removing the solvent or solvent mixture.

El 1. A process according to Clauses E8 or E10 wherein the reaction mixture in step (i) is a slurry.

E12. A process according to Clauses E8 or Ell, wherein the Firibastat provided as starting material is in a non-hydrated form.

E13. A process according to any of Clauses E8, El 1 or E12, wherein the solvent is a polar solvent, preferably an alcohol, more preferably isopropanol.

E14. A process according to any one of clauses E8, Ell, E12 or E13 wherein the reaction mixture is optionally heated to a temperature of about 30 °C to about 50 °C.

E15. A process according to any one of clauses E8, Ell, E12, E13 or E14 wherein in step (ii) the solvent is separated by centrifuge.

El 6. A process according to any one of clauses E8-E15 wherein the molar ration of Firibastat to L-Proline is from about 1:4 to about 4:1, preferably from about 1:3 to about 3:1, more preferably the ratio is about 1:2.

E17. A process according to any one of Clauses E8-E16 further comprising combining the crystalline product with at least one pharmaceutically acceptable excipient to provide a pharmaceutical composition. E18. A crystalline product obtainable by a process according to any one of Claims E8-E16.

E19. A pharmaceutical composition comprising a crystalline product according to any of Clauses E1-E7 or E18, and at least one pharmaceutically acceptable excipient.

E20. Else of a crystalline product according to any of Clauses E1-E7 or E18 for the preparation of a pharmaceutical composition and/or formulation.

E21. A process for preparing the pharmaceutical composition according to Clause El 9, comprising combining a crystalline product according to any of Clauses E1-E7 or E18 with at least one pharmaceutically acceptable excipient.

E22. A crystalline product according to any of Clauses E1-E7 or E18, or a pharmaceutical composition according to Clause El 9, for use as a medicament.

E23. A crystalline product according to any of Clauses E1-E7 or Cl 8, or a pharmaceutical composition according to Clause E19, for use in the treatment of hypertension.

E24. A method of treating hypertension comprising administering a therapeutically effective amount of a crystalline product according to any of Clauses E1-E7 or El 8, or a pharmaceutical composition according to Clause El 9, to a subject in need of the treatment.

E25. Else of a crystalline product according to any of Clauses E1-E7 or E18, in the preparation of another solid state form of Firibastat: L-Proline or Firibastat salt.

E26. A process for preparing a solid state form of Firibastat: L-Proline or Firibastat salt comprising preparing any one or a combination of a crystalline product according to any one of Clauses E1-E7 or E18, and converting it to another a solid state form thereof or Firibastat salt.

Powder X-ray Diffraction C'XRPD") method

[00169] XRPD analysis was performed on Bruker powder X-Ray diffractometer model D8 ADVANCE equipped with a solid state detector. Copper radiation of 1.54060 A was used. Scanning parameters: range: 2-40 degrees two-theta; scan mode; step size: 0.05°.

The positions of the peaks were corrected respective to the position of the silicon theoretical peak at 28.45 degrees two theta. Solid-state NMR

[00170] Solid-state NMR spectra were measured at 11.7 T using a Bruker Avance III HD 500 US/WB NMR spectrometer (Karlsruhe, Germany, 2013). The 13C CPMAS NMR spectra employing cross-polarization were acquired using the standard pulse scheme at spinning frequency of 18 kHz. The recycle delay was 8 s and the cross-polarization contact time was 2 ms. The strength of spin-locking fields B1(13C) expressed in frequency units w1/2p=gB1 was 64 kHz.

EXAMPLES

Preparation of starting materials

[00171] Firibastat can be prepared according to methods known from the literature, for example as described in International Publication No. WO 2004/007441.

Example 1: Preparation of crystalline Firibastat

[00172] Water (10 ml, 10V) was added to Firibastat (lgram, 2.7 mmol) to obtain a slurry. The slurry was magnetically stirred and heated to 40°C over a period of 10 minutes to obtain complete dissolution followed by filtration using filter disk. Next, Isopropyl alcohol as anti solvent (13 ml) was added drop-wise to the stirred clear solution at 40°C. The solution was cooled to room temperature and then stirred at room temperature during 18 hours. The obtained precipitation was then separated by centrifuge to afford a white wet solid and dried in a vacuum oven at 45°C over a period of 16 hours to afford a white solid. Next, the dry solid was exposed to 100% relative humidity (RH) at room temperature for 6 days to afford a white solid.

Example 2: Preparation of Firibastat Form HI Procedure A

[00173] Mixture of Diehl orom ethane and Acetonitrile (1:1, 60 ml, 200V) was added to

Firibastat (300 mg, 0.81 mmol, prepared according to example 1), to obtain a slurry. The slurry was stirred at 60°C over a period of 48 hours. Then was cooled to room temperature and was separated by centrifuge. Then, the solid was dried in a vacuum oven at 60 °C over a period of 16 hours to afford white solid, which was characterized by X-ray powder diffraction as Firibastat crystal Form HI and the XRPD pattern is presented in Figure 1. Procedure B

[00174] Dioxane (60 ml, 200V) was added to Firibastat (40 mg, 0.1 mmol, prepared according to example 1) to obtain a slurry. The slurry was stirred at 60°C over a period of 48 hours. The obtained slurry was cooled to room temperature and then was separated by centrifuge. The wet solid was analyzed by X-ray powder diffraction and identified as Firibastat crystal Form HI.

Example 3: Preparation of Firibastat Form H2 Procedure A

[00175] Water (0.5 ml, 10V) was added to Firibastat (50 mg, 0.13 mmol) to obtain a slurry. The slurry was magnetically stirred and heated to 40°C over a period of 10 minutes to obtain complete dissolution followed by filtration using filter disk. Next, Acetone as anti-solvent (0.5 ml) was added drop-wise to the stirred clear solution at 40°C. The solution was cooled to room temperature and then stirred at room temperature during 18 hours. The obtained precipitate was then separated by centrifuge to afford a white wet solid and dried in a vacuum oven at 45°C over a period of 16 hours to afford a white solid, which was characterized by X-ray powder diffraction as Firibastat crystal Form H2 and the XRPD pattern is presented in Figure 2.

Example 4: Preparation of Firibastat Form A Procedure A

[00176] Ethanol (6 ml, 20V) was added to Firibastat (300 mg, 0.81 mmol, prepared according to example 3, procedure A, and 1,2-Ethanedisulfonic acid dihydrate (72 mg, 0.3 mmol) to obtain a slurry. The slurry was magnetically stirred and heated to 40°C. The slurry was stirred at 40°C over a period of 72 hours, then was cooled to room temperature and was separated by centrifuge followed by washing with Ethanol (3*1 ml). The wet solid was dried in a vacuum oven at 60°C over a period of 16 hours to afford a white solid, which was characterized by X-ray powder diffraction as Firibastat crystal Form A and the XRPD pattern is presented in Figure 3.

Procedure B

[00177] Ethanol (3 ml, 10V) was added to Firibastat (300 mg, 0.81 mmol, prepared according to example 3, procedure A) and Benzathine (0.2 ml, 0.83 mmol) to obtain a slurry. The slurry was magnetically stirred and heated to 40°C. The slurry was stirred at 40°C over a period of 24 hours, then was cooled to room temperature and was separated by centrifuge followed by washing with Ethanol (3*1 ml). The white wet solid was dried in a vacuum oven at 60°C over a period of 16 hours to afford a white solid, which was analyzed by X-ray powder diffraction and identified as Firibastat crystal Form A.

Procedure C

[00178] Ethanol (1 ml, 10V) was added to Firibastat (100 mg, 0.21 mmol, prepared according to example 3, procedure A) and Benzathine (0.03 ml, 0.13 mmol) to obtain a slurry. The slurry was magnetically stirred and heated to 40°C. The slurry was stirred at 40°C over a period of 72 hours, then was cooled to room temperature and was separated by centrifuge followed by washing with Ethanol (3*1 ml). The wet solid was dried in a vacuum oven at 60°C over a period of 16 hours to afford a white solid, which was analyzed by X-ray powder diffraction and identified as Firibastat crystal Form A.

Procedure D

[00179] Ethanol (1 ml, 10V) was added to Firibastat (100 mg, 0.21 mmol, prepared according to example 1) and Benzathine (0.07 ml, 0.26 mmol) to obtain a slurry. The slurry was magnetically stirred and heated to 40°C. The slurry was stirred at 40°C over a period of 24 hours, then was cooled to room temperature and was separated by centrifuge. The wet solid was dried in a vacuum oven at 40°C over a period of 16 hours to afford a white solid, which was analyzed by X-ray powder diffraction and identified as Firibastat crystal Form A.

Procedure E

[00180] Isopropyl alcohol (0.5 ml, 10V) was added to Firibastat (50 mg, 0.12 mmol, prepared according to example 3, procedure A) and Benzathine (0.07 ml, 0.26 mmol) to obtain a slurry. The slurry was magnetically stirred and heated to 40°C. The slurry was stirred at 40°C over a period of 48 hours, then was cooled to room temperature and was separated by centrifuge. The wet solid was dried in a vacuum oven at 60°C over a period of 16 hours to afford a white solid, which was analyzed by X-ray powder diffraction and identified as Firibastat crystal Form A.

Procedure F

[00181] Ethanol (50 ml, 20V) was added to Firibastat (2.5 grams, 6.8 mmol), prepared according to example 2, procedure B, and 1,2-Ethanedisulfonic acid dihydrate (600 mg, 2.5 mmol) to obtain a slurry. The slurry was magnetically stirred and heated to 40°C. The slurry was stirred at 40°C over a period of 48 hours, then was cooled to room temperature and stirred for 120 hours. Then, the solid was separated by Buchner followed by washing with Ethanol (3*7.5 ml). The wet solid was dried in a vacuum oven at 60°C over a period of 16 hours to afford a white solid, which was characterized by X-ray powder diffraction as Firibastat crystal Form A.

Procedure G

[00182] Ethanol (1 ml, 20V) was added to Firibastat (57 mg, 0.15 mmol), prepared according to example 2, procedure B, and 98% FbSCri (29 mΐ) to obtain a slurry. The slurry was magnetically stirred and heated to 40°C over a period of 48 hours. Then, the solid was separated by centrifuge. The wet solid was characterized by X-ray powder diffraction as Firibastat crystal Form A.

Procedure H

[00183] Ethanol (11.4 ml, 20V) was added to Firibastat (570 mg, 1.5 mmol), prepared according to example 2, procedure B, and 98% FbSCE (298 mΐ) to obtain a slurry. The slurry was magnetically stirred and heated to 40°C over a period of 72 hours. Then, the solid was separated by centrifuge. The wet solid was suspended in Ethanol (11.4 ml, 20V) to obtain slurry and 98% H ₂ SO ₄ (298 mΐ) was added. The slurry was magnetically stirred and heated to 40°C over a period of 48 hours. Then, the solid was separated by centrifuge and dried in a vacuum oven at 60°C over a period of 16 hours to afford a white solid, which was characterized by X-ray powder diffraction as Firibastat crystal Form A.

Procedure

[00184] Ethanol (1 ml, 20V) was added to Firibastat (57 mg, 0.15 mmol), prepared according to example 2, procedure B, and Methansulfonic acid (17.6 mΐ) to obtain a slurry. The slurry was magnetically stirred and heated to 40°C over a period of 16 hours. Then, the solid was separated by centrifuge. The wet solid was characterized by X-ray powder diffraction as Firibastat crystal Form A.

Procedure J

[00185] Ethanol (1 ml, 20V) was added to Firibastat (57 mg, 0.15 mmol), prepared according to example 2, procedure B, and P-Toluenesulfonic acid monohydrate (27 mg) to obtain a slurry. The slurry was magnetically stirred and heated to 40°C over a period of 16 hours. Then, the solid was separated by centrifuge. The wet solid was characterized by X-ray powder diffraction as Firibastat crystal Form A. Example 5: Preparation of Firibastat Form B

Procedure A

[00186] Acetic acid (4 ml, 20V) was added to Firibastat (200 mg, 0.54 mmol, prepared according to example 3, procedure A) to obtain a slurry. The slurry was magnetically stirred and heated to 60°C. The slurry was stirred at 60°C over a period of 48 hours, then was cooled to room temperature and was separated by centrifuge. The wet solid was dried in a vacuum oven at 60°C over a period of 16 hours to afford a white solid, which was characterized by X-ray powder diffraction as Firibastat crystal Form B and the XRPD pattern is presented in Figure 4.

Procedure B

[00187] Acetic acid (1 ml, 20V) was added to Firibastat (50 mg, 0.13 mmol, prepared according to example 1) to obtain a slurry. The slurry was magnetically stirred and heated to 60°C. The slurry was stirred at 60°C over a period of 48 hours, then was cooled to room temperature and was separated by centrifuge. The wet solid was dried in a vacuum oven at 60°C over a period of 16 hours to afford a white solid, which was analyzed by X-ray powder diffraction and identified as Firibastat crystal Form B.

Procedure C

[00188] Propionic acid (1 ml, 20V) was added to Firibastat (50 mg, 0.13 mmol prepared according to example 3, procedure A) to obtain a slurry. The slurry was magnetically stirred and heated to 60°C. The slurry was stirred at 60°C over a period of 48 hours, then was cooled to room temperature and was separated by centrifuge. The wet solid was dried in a vacuum oven at 45°C over a period of 16 hours to afford a white solid, which was characterized by X-ray powder diffraction as Firibastat crystal Form B.

Procedure D

[00189] Acetic acid (16.2 ml, 20V) was added to Firibastat (812 mg, 2.2 mmol, prepared according to example 2, procedure B) to obtain a slurry. The slurry was magnetically stirred and heated to 60°C. The slurry was stirred at 60°C over a period of 48 hours, then was cooled to room temperature and was separated by centrifuge. The wet solid was dried in a vacuum oven at 60°C over a period of 16 hours to afford a white solid, which was characterized by X-ray powder diffraction as Firibastat crystal Form B. Example 6: Preparation of Firibastat Crystal Form El

Procedure A

[00190] Toluene (11 ml, 20V) was added to Firibastat (536.5 mg, 1.35 mmol, prepared according to example 3, procedure A) and 1,2-Ethanedisulfonic acid dihydrate (298 mg, 1.35 mmol, 1:1 eq) to obtain a slurry. The slurry was magnetically stirred and heated to 40°C. The slurry was stirred at 40°C over a period of 48 hours, then was cooled to room temperature and was separated by centrifuge. The wet solid and dried in a vacuum oven at 60°C over a period of 16 hours to afford a white solid, which was characterized by X-ray powder diffraction as Firibastat crystal Form El and the XRPD pattern is presented in Figure 5.

Procedure B

[00191] Tetrahydrofuran (6 ml, 20V) was added to Firibastat (50 mg, 0.12 mmol, prepared according to example 3, procedure A) and 1,2-Ethanedisulfonic acid dihydrate (24 mg, 0.11 mmol) to obtain a slurry. The slurry was magnetically stirred at room temperature over a period of 48 hours and then was separated by centrifuge. The wet solid was dried in a vacuum oven at 45°C over a period of 16 hours to afford a white solid, which was analyzed by X-ray powder diffraction and identified as Firibastat crystal Form El.

Procedure C

[00192] Ethyl acetate (11 ml, 20V) was added to Firibastat (536.5 mg, 1.35 mmol, prepared according to example 3, procedure A) and 1,2-Ethanedisulfonic acid dihydrate (298 mg, 1.35 mmol, 1:1 eq) to obtain a slurry. The slurry was magnetically stirred and heated to 40°C. The slurry was stirred at 40°C over a period of 48 hours, then was cooled to room temperature and was separated by centrifuge. The wet solid and dried in a vacuum oven at 60°C over a period of 16 hours to afford a white solid, which was characterized by X-ray powder diffraction as Firibastat crystal Form El.

Procedure D

[00193] Mixture of Ethyl acetate: Toluene (1 :2, 10 ml, 20V) was added to Firibastat Form A (500 mg, 1.35 mmol, example 4, procedure F) and 1,2-Ethanedisulfonic acid dihydrate (278 mg, 1.26 mmol) to obtain a slurry. The slurry was magnetically stirred and heated to 40°C. The slurry was stirred at 40°C over a period of 48 hours, then was cooled to room temperature and was separated by centrifuge. The wet solid and dried in a vacuum oven at 60°C over a period of 72 hours to afford a white solid, which was characterized by X-ray powder diffraction as Firibastat crystal Form El.

Example 7: Preparation of Firibastat: piperazine Form PI Procedure A

[00194] Water (2.3 ml, 46V) was added to Firibastat (50 mg, 0.13 mmol) to obtain a slurry. The slurry was stirred at room temperature to obtain clear solution. Then, a clear solution of piperazine in water (23.4 mg, 0.27 mmol in 0.16 ml) was added to the clear solution of Firibastat. The obtained clear mother-liquor was evaporated upon 70°C/300-35 mbar to give a precipitate. The obtained wet solid was dried in a vacuum oven at 60 °C over a period of 16 hours to afford a white solid, which was characterized by X-ray powder diffraction as Firibastat: Piperazine crystal Form PI and the XRPD pattern is presented in Figure 6.

Procedure B

[00195] Isopropyl alcohol (0.93 ml, 10V) was added to piperazine (93.6 mg, 1.08 mmol) to obtain clear solution. Then, Firibastat prepared according to example 1, (200 mg, 0.54 mmol) was added to the clear solution of piperazine in IPA to obtain slurry. Additional portion of 1.064 ml of isopropyl alcohol was added to the stirred slurry. The slurry was then heated to 40°C and stirred at 40°C for 16 hours. The obtained wet solid was separated by centrifuge and washed twice with 1 ml IPA. The obtained solid was dried in a vacuum oven at 60 °C over a period of 16 hours to afford a white solid, which was analyzed by X-ray powder diffraction and identified as Firibastat: Piperazine crystal Form PI.

Procedure C

[00196] Isopropyl alcohol (4.67 ml, 10V) was added to piperazine (467.5 mg, 5.4 mmol) to obtain clear solution. Then, Firibastat (1000 mg, 2.7 mmol, prepared according to example 2, procedure B) was added to the clear solution of piperazine in IPA to obtain slurry. Additional portion of 5.32 ml of isopropyl alcohol was added to the stirred slurry. The slurry was then heated to 40°C and stirred at 40°C for 16 hours. The obtained wet solid was separated by centrifuge and washed twice with 2 ml IPA. The obtained solid was dried in a vacuum oven at 60 °C over a period of 16 hours to afford a white solid, which was analyzed by X-ray powder diffraction and identified as Firibastat: Piperazine crystal Form PI. Example 8: Preparation of Firibastat: L-Proline Form P2 Procedure A

[00197] Isopropyl alcohol (8 ml, 20V) was added to Firibastat Form A (that can be prepared according to example 4, procedure A) (400 mg, 1.08 mmol) to obtain a slurry. Then, L-Proline (250 mg) was added to the slurry. The slurry was then heated to 40°C and stirred at 40°C for 48 hours. The obtained wet solid was separated by centrifuge and was dried in a vacuum oven at 45 °C over a period of 16 hours to afford a white solid, which was characterized by X-ray powder diffraction as Firibastat: L-Proline crystal Form P2 and the XRPD pattern is presented in Figure 7.

Procedure B

[00198] Water (2.3 ml, 46V) was added to Firibastat (50 mg, 0.13 mmol) to obtain a slurry. The slurry was stirred at room temperature to obtain a clear solution. Then, a clear solution of L- Proline in water (31.2 mg in 0.1 ml) was added to the clear solution of Firibastat. The obtained clear mother-liquor was evaporated upon 70°C/300-35 mbar to give a precipitate. The obtained white solid was analyzed by X-ray powder diffraction and identified as Firibastat: L-Proline crystal Form P2.