Patent Application
20210340149
The instant application is directed to novel crystalline forms of 3-(imidazo[1,2-b]pyridazin-3-ylethynyl)-4-methyl-N-{4-[(4-methylpiperazin-1-yl)methyl]-3-(trifluoromethyl)phenyl}benzamide and 3-(imidazo[1,2-b]pyridazin-3-ylethynyl)-4-methyl-N-{4-[(4-methylpiperazin-1-yl)methyl]-3-(trifluoromethyl)phenyl}benzamide mono hydrochloride, compositions comprising such crystalline forms, and to methods of their preparation and use.
3-(Imidazo[1,2-b]pyridazin-3-ylethynyl)-4-methyl-N-{4-[(4-methylpiperazin-1-yl)methyl]-3-(trifluoromethyl)phenyl}benzamide has the chemical formula C29H27F3N6O which corresponds to a formula weight of 532.56 g/mol. Its chemical structure is shown below:
The CAS Registry number for 3-(imidazo[1,2-b]pyridazin-3-ylethynyl)-4-methyl-N-{4-[(4-methylpiperazin-1-yl)methyl]-3-(trifluoromethyl)phenyl}benzamide is 943319-70-8.
3-(Imidazo[1,2-b]pyridazin-3-ylethynyl)-4-methyl-N-{4-[(4-methylpiperazin-1-yl)methyl]-3-(trifluoromethyl)phenyl}benzamide mono hydrochloride has the chemical formula C29H28ClF3N6O which corresponds to a formula weight of 569.02 g/mol. Its chemical structure is shown below:
The CAS Registry number for 3-(imidazo[1,2-b]pyridazin-3-ylethynyl)-4-methyl-N-{4-[(4-methylpiperazin-1-yl)methyl]-3-(trifluoromethyl)phenyl}benzamide mono hydrochloride is 1114544-31-8.
The United States Adopted Name (USAN) and International Nonproprietary Name (INN) of 3-(imidazo[1,2-b]pyridazin-3-ylethynyl)-4-methyl-N-{4-[(4-methylpiperazin-1-yl)methyl]-3-(trifluoromethyl)phenyl}benzamide is ponatinib. Alternative chemical names for ponatinib include benzamide, 3-(2-imidazo[1,2-b]pyridazin-3-ylethynyl)-4-methyl-N-[4-[(4-methyl-1-piperazinyl)methyl]-3-(trifluoromethyl)phenyl] and 3-[2-(imidazo[1,2-b]pyridazin-3-yl)ethynyl]-4-methyl-N-{4-[(4-methylpiperazin-1-yl)methyl]-3-(trifluoromethyl)phenyl}benzamide.
The United States Adopted Name (USAN) and International Nonproprietary Name (INN) of 3-(imidazo[1,2-b]pyridazin-3-ylethynyl)-4-methyl-N-{4-[(4-methylpiperazin-1-yl)methyl]-3-(trifluoromethyl)phenyl}benzamide mono hydrochloride is ponatinib hydrochloride. Alternative chemical names for ponatinib hydrochloride include benzamide, 3-(2-imidazo[1,2-b]pyridazin-3-ylethynyl)-4-methyl-N-[4-[(4-methyl-1-piperazinyl)methyl]-3-(trifluoromethyl)phenyl]-, hydrochloride (1:1) and 3-[2-(imidazo[1,2-b]pyridazin-3-yl)ethynyl]-4-methyl-N-{4-[(4-methylpiperazin-1-yl)methyl]-3-(trifluoromethyl)phenyl}benzamide monohydrochloride.
Ponatinib is a multi-targeted tyrosine-kinase inhibitor useful for the treatment of chronic myeloid leukemia (CML) and other diseases. Ponatinib hydrochloride is a small molecule pan-BCR-ABL inhibitor in clinical development for the treatment of adult patients with chronic phase, accelerated phase, or blast phase CML or Philadelphia chromosome positive acute lymphoblastic leukemia (Ph+ALL) resistant or intolerant to prior tyrosine-kinase inhibitor therapy. Other tyrosine-kinase inhibitors relevant to such CML or Ph+ALL therapy include GLEEVEC® (imatinib mesylate) and TASIGNA® (nilotinib) (both from Novartis AG), SPRYCEL® (dasatinib) (from Bristol Myers Squibb Company) and BOSULIF® (bosutinib) (from Pfizer Inc). A New Drug Application (NDA) for ponatinib hydrochloride was filed with the United States FDA on Jul. 30, 2012. The US FDA approved the NDA on Dec. 14, 2012, and ponatinib hydrochloride is marketed under the brand name ICLUSIG® (ponatinib).
In addition, ponatinib hydrochloride is potentially clinically useful for the treatment of other disorders or conditions implicated by the inhibition of other protein kinases. Such kinases and their associated disorders or conditions are mentioned in O'Hare, T., et al., Cancer Cell, Volume 16, Issue 5, 401-412 (2009) and WO 2011/053938, both of which are hereby incorporated herein by reference for all purposes.
Having an understanding of the potential polymorphic forms for active pharmaceutical ingredients (API) such as ponatinib and ponatinib hydrochloride is useful in the development of drugs. This is because not knowing the specific polymorphic form present or desired in the API may result in inconsistent manufacturing of the API and as a result, results with the drug may vary between various lots of the API. In addition, it is important to discover the potential polymorphic forms of an API so that one can systematically determine the stability of that form over a prolonged period of time for similar reasons. Once a specific polymorphic form is selected for pharmaceutical development, it is important to be able to reproducibly prepare that polymorphic form. It is also desirable for there to be a process for making APIs such as ponatinib and ponatinib hydrochloride in high purity due to the potential for impurities to affect the performance of the drug.
The earliest patent publication known by Applicant to disclose the chemical structure of ponatinib hydrochloride is WO 2007/075869, which is also owned by Applicant (ARIAD Pharmaceuticals, Inc.) and is hereby incorporated herein by reference for all purposes. Example 16 of WO 2007/075869 states that the product was obtained as a solid: 533 m/z (M+H). This mass corresponds to the free base of ponatinib. Example 16 also discusses the preparation of a mono hydrochloride salt of ponatinib. Example 16 neither specifically mentions that the ponatinib hydrochloride obtained was crystalline, nor specifies any particular crystalline forms of ponatinib hydrochloride.
U.S. Ser. No. 11/644,849, which published as US 2007/0191376, is a counterpart application to WO 2007/075869 and granted on Feb. 14, 2012 as U.S. Pat. No. 8,114,874, which is hereby incorporated herein by reference for all purposes. U.S. Ser. No. 13/357,745 is a continuing application of U.S. Ser. No. 11/644,849, which also is hereby incorporated herein by reference for all purposes.
Additional patent applications owned by Applicant that cover ponatinib hydrochloride and published as of the filing date of this application include WO 2011/053938 and WO 2012/139027, both of which are hereby incorporated herein by reference for all purposes. Like WO 2007/075869, neither of WO 2011/053938 or WO 2012/139027 specifies any particular crystalline forms of ponatinib hydrochloride.
It has now been discovered that both ponatinib and ponatinib hydrochloride can exist in certain crystalline and other polymorphic forms, certain of which are suitable for pharmaceutical formulation development.
In one aspect, the present disclosure is directed to polymorphs of ponatinib. The polymorphs of ponatinib are herein designated as Form A, Form B, Form C, Form D, Form E, Form F, Form G, Form H, Form I, Form J, and Form K.
In another aspect, the present disclosure is directed to pharmaceutical compositions comprising a therapeutically effective amount of a polymorph of ponatinib disclosed herein and at least one pharmaceutically acceptable carrier, vehicle or excipient.
In another aspect, the present disclosure is directed to substantially pure crystalline forms of ponatinib hydrochloride. The substantially pure crystalline forms of ponatinib hydrochloride are herein designated as Form A, Form B, Form C, Form D, Form E, Form F, Form G, Form H, Form I, Form J, and Form K.
In another aspect, the present disclosure is directed to pharmaceutical compositions comprising a therapeutically effective amount of a substantially pure crystalline form of ponatinib hydrochloride disclosed herein and at least one pharmaceutically acceptable carrier, vehicle or excipient.
In another aspect, the present disclosure provides a process for preparing a substantially pure crystalline form of ponatinib hydrochloride by contacting ponatinib with hydrochloric acid.
In another aspect, the present disclosure is directed to a method of treating a disorder or condition in a human that responds to the inhibition of a protein kinase by administering to the human a therapeutically effective amount of a polymorph of ponatinib disclosed herein. In certain embodiments, the disorder or condition is chronic myeloid leukemia (CML).
In another aspect, the present disclosure is directed to a method of treating a disorder or condition in a human that responds to the inhibition of a protein kinase by administering to the human a therapeutically effective amount of a substantially pure crystalline form of ponatinib hydrochloride disclosed herein. In certain embodiments, the disorder or condition is chronic myeloid leukemia (CML) or Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph+ALL) when the protein kinase is Bcr-Abl or a mutant form thereof.
The following drawings form part of the present specification and are included to further demonstrate certain aspects of the present inventions. The inventions may be better understood by reference to one or more of these drawings in combination with the detailed description of specific embodiments presented herein.
It was discovered that both 3-(imidazo[1,2-b]pyridazin-3-ylethynyl)-4-methyl-N-{4-[(4-methylpiperazin-1-yl)methyl]-3-(trifluoromethyl)phenyl}benzamide and 3-(imidazo[1,2-b]pyridazin-3-ylethynyl)-4-methyl-N-{4-[(4-methylpiperazin-1-yl)methyl]-3-(trifluoromethyl)phenyl}benzamide mono hydrochloride can be obtained in various solid state crystalline forms.
The terms “crystalline form” or “polymorphic form” or “polymorph” may be used interchangeably herein, and refer to a crystalline form of pontinib or ponatinib hydrochloride that is distinct from the amorphous form of ponatinib or ponatinib hydrochloride or other form(s) of ponatinib or ponatinib hydrochloride as determined by certain physical properties such thermodynamic stability, physical parameters, x-ray structure, DSC and preparation processes.
While polymorphism classically refers to the ability of a compound to crystallize into more than one distinct crystal species (having identical chemical structure but quite different physicochemical properties), the term “pseudopolymorphism” is typically applied to solvate and hydrate crystalline forms. For purposes of this disclosure, however, both true polymorphs as well as pseudopolymorphs, (i.e., hydrate and solvate forms), are included in the scope of the term “crystalline forms” and “polymorphic forms.” In addition, “amorphous” refers to a disordered solid state.
It should be noted that different samples of a particular crystalline form may share the same major XRPD peaks, but that there can be variation in XRPD patterns with regard to the minor peaks. In regards to XRPD, the term “about,” when used in relation to XRPD maxima values (in degrees two theta), generally means within 0.3 degrees two theta of the given value. Alternatively, the term “about” can mean (in this and all contexts) a value falls within an accepted standard of error of the mean when considered by one of ordinary skill in the art. As used herein, the terms “isolated” and “substantially pure” mean that more than about 50% of crystalline ponatinib or ponatinib hydrochloride is present (as can be determined by a method in accordance with the art) in the identified crystalline form relative to the sum of other solid form(s) present in the selected material.
Other Abbreviations (Alphabetical Order):
XRPD patterns were obtained using an Avantium T2 high-throughput XRPD set-up. The plates were mounted on a Bruker GADDS diffractometer equipped with a Hi-Star area detector. The XRPD platform was calibrated using Silver Behenate for the long d-spacings and Corundum for the short d-spacings.
Data collection was carried out at room temperature using monochromatic CuKα radiation in the 2θ region between 1.5° and 41.5°, which is the most distinctive part of the XRPD pattern. The diffraction pattern of each well was collected in two 2θ ranges (1.5°≤2θ≤21.5° for the first frame, and 19.5°≤2θ≤41.5° for the second) with an exposure time of 90 seconds for each frame. No background subtraction or curve smoothing was applied to the XRPD patterns. The carrier material used during XRPD analysis was transparent to X-rays and contributed only slightly to the background.
Melting properties were obtained from DSC thermograms, recorded with a heat flux DSC822e instrument (Mettler-Toledo GmbH, Switzerland). The DSC822e was calibrated for temperature and enthalpy with a small piece of indium (m.p.=156.6° C.; ΔHf=28.45 J·g−1). Samples were sealed in standard 40 μl aluminum pans, pin-holed and heated in the DSC from 25° C. to 300° C., at a heating rate of 10° C. min−1. Dry N2 gas, at a flow rate of 50 ml min−1 was used to purge the DSC equipment during measurement.
Mass loss due to solvent or water loss from the various crystal samples was determined by TGA/SDTA. Monitoring the sample weight, during heating in a TGA/SDTA851e instrument (Mettler-Toledo GmbH, Switzerland), resulted in a weight vs. temperature curve. The TGA/SDTA851e was calibrated for temperature with indium and aluminum. Samples were weighed into 100 μl aluminum crucibles and sealed. The seals were pin-holed and the crucibles heated in the TGA from 25 to 300° C. at a heating rate of 10° C. min−1. Dry N2 gas was used for purging.
The gases evolved from the TGA samples were analyzed by a mass spectrometer Omnistar GSD 301 T2 (Pfeiffer Vacuum GmbH, Germany). The latter is a quadrupole mass spectrometer which analyses masses in the range of 0-200 amu.
Digital images were automatically collected for all the wells of each well-plate, employing a Philips PCVC 840K CCD camera controlled by Avantium Photoslider software.
For the compression tests, an Atlas Power Press T25 (Specac) was used. The Atlas Power T25 is a power assisted hydraulic press operating up to 25 Tons.
HPLC analysis was performed using an Agilent 1200SL HPLC system equipped with UV and MS detectors following the conditions presented below:
The compound integrity is expressed as a peak-area percentage, calculated from the area of each peak in the chromatogram, except the ‘injection peak’, and the total peak-area, as follows:
The peak-area percentage of the compound of interest is employed as an indication of the purity of the component in the sample.
Through XRPD analysis, a total of eleven polymorphic forms of ponatinib hydrochloride were discovered. Each of the eleven new polymorphic forms are referred to herein as: HCl1 (also referred to herein as “Form A”), HCl2 (also referred to herein as “Form B”), HCl2b (also referred to herein as “Form C”), HCl3-class (also referred to herein as “Form D”), a mixture HCl1+HCl4 (also referred to herein as “Form E”), HCl5-class or simply HCl5 (also referred to herein as “Form F”), HCl5b or HCl5 desolvate (also referred to herein as “Form G”), HCl6-class (also referred to herein as “Form H”), HCl6 desolvate (also referred to herein as “Form I”), HCl7 (also referred to herein as “Form J”), and HCl8 (also referred to herein as “Form K”). The nature or origin of these eleven polymorphic forms is indicated in
In general, crystalline forms of ponatinib hydrochloride have physical properties (such as high stability, etc.) that are advantageous for the commercial preparation of solid dosage forms as compared to amorphous ponatinib hydrochloride. The distinction between crystalline ponatinib hydrochloride and amorphous ponatinib hydrochloride can be readily seen with the same type of physical chemical data (e.g., DSC, XRPD, thermal analysis) that is used to distinguish the individual crystalline forms of ponatinib hydrochloride disclosed herein.
With reference to the foregoing methodologies, attention is now drawn to each of the discovered polymorphs of 3-(imidazo[1,2-b]pyridazin-3-ylethynyl)-4-methyl-N-{4-[(4-methylpiperazin-1-yl)methyl]-3-(trifluoromethyl)phenyl}benzamide mono hydrochloride.
The anhydrate HCl1 (same crystalline form as the starting material) was the predominant crystalline form discovered. The chemical structure of ponatinib hydrochloride has been unambiguously established by a combination of nuclear magnetic resonance spectroscopy (NMR), mass spectrometry (MS), and single crystal X-ray crystallography with confirmatory data from elemental and chloride analysis, Fourier transform infra-red (FT-IR) spectroscopy, and ultraviolet (UV) spectroscopy. The preferred solid form of ponatinib hydrochloride is the anhydrous crystalline HCl-1 solid form or Form A.
With reference to
In differential vapor sorption (DVS) experiment with HCl-1, the relative humidity was cycled from 45% to 95% (sorption), to 0% (desorption) and back to 45% (sorption) at a constant temperature of 25° C., with a hold time of 60 minutes per step. The results of this DVS experiment on ponatinib HCl CGAM Batch F08-060507 exhibited a 1.1% water uptake at 95% humidity, and ponatinib HCl ASI Batch 110020 exhibited a 1.4% water uptake at a relative humidity of 95%. This water uptake was reversible on cycling to lower humidity. These results demonstrate that HCl-1 is not a hygroscopic compound. The effect of the humidity cycling on HCl-1 was also assessed by X-ray powder diffraction (XRPD) analysis before and after the DVS experiment. The XRPD data revealed that humidity cycling had no effect on the solid form of the material, which remained in the HCl-1 solid form.
With reference to
With reference to
Extensive solution phase NMR studies using a combination of multiple 1D and 2D NMR methods were performed on Form A of ponatinib HCl to obtain a complete assignment of 1H, 19F, and 13C resonances, and hence to confirm the chemical structure of ponatinib HCl. Analyses were performed at ARIAD Pharmaceuticals, Inc., Cambridge, Mass., on a sample of ponatinib HCl (ASI Batch 110020) dissolved in deuterated DMSO (DMSO-ds) solvent. NMR spectra were acquired at a temperature of 300 K on a Bruker Avance III-600 MHz NMR spectrometer equipped with a 5 mm BBFO z-gradient probe. All 1H chemical shifts were referenced to the DMSO peak at 2.5 ppm. With reference to
Table 1 summarizes the relevant chemical shift data of ponatinib mono hydrochloride Form A obtained from the 1H and 13C-NMR experiments. The number of signals and their relative intensity (integrals) confirm the number of protons and carbons in the structure of Form A of ponatinib HCl. These chemical shift data are reported in according to the atom numbering scheme shown immediately below:
1H and 13C Chemical Shift Data (in ppm) of Form A of ponatinib
1H, ppm
13C, ppm
1H Multiplicity, Hz
13C Multiplicity, Hz
19F: −57.9
With reference to
Single-crystal X-Ray diffraction analysis was employed to determine the crystal structure of the Form A of ponatinib hydrochloride. Single crystals of ponatinib HCl, in the anhydrate HCl-1 form were obtained using the vapor diffusion into liquid crystallization method using ponatinib HCl CGAM Batch F08-06057. A single crystal obtained using methanol as a solvent with ethyl acetate as anti-solvent was analyzed by single crystal X-ray diffraction. From prior experiments, it was known that crystals of this form diffracted well, leading to the solution of the structure of ponatinib HCl shown in
The attenuated total reflectance (ATR) FT-IR spectrum of Form A of ponatinib HCl, ASI Batch 110020, is shown in
In the FT-IR, the functional group region extends from 4000 to 1300 cm-1. In the region from 3300 to 2800 cm-1 (region A), there are multiple overlapping, absorption bands arising from stretching vibrations between hydrogen and some other atom, likely amide N—H stretching, aromatic C—H stretching (from the imidazo-pyridazine heterocycle and phenyl groups) and aliphatic C—H stretching (in methyl and methylene groups), all present in the structure of ponatinib HCl. A weak band in the 2100-2260 cm-1 (region B) is due to triple C—C bond stretching. A medium intensity band due to amide C═O stretching (Amide 1) can be expected in 1640-1690 cm-1 range, likely the band observed at 1669.8 cm-1(region C). Secondary amide N—H bending gives absorption bands in the 1500-1560 cm-1 range (Amide 2), where two strong bands are observed (region D). Multiple weak to medium bands observed in the 1300-1600 cm-1 range are due to (hetero)aromatic resonance-stabilized double C—C and double C—N bonds (ring stretching vibrations), and C—H bending vibrations (from methyl and methylene groups) (region E). Aromatic and aliphatic amine C—N stretching bands can be expected in the 1250-1335 cm-1 range and in the 1250-1020 cm-1 range, respectively, where multiple bands are observed, including a particularly strong band at 1314.9 cm-1 (regions F, G). The fingerprint region, 1300 to 910 cm-1, is complex with a strong, broad band at 1122.6 cm-1 (region H), likely due to C—F stretching. The aromatic region, 910 to 650 cm-1, absorption bands are primarily due to the out-of-plane bending of hetero-aromatic ring C—H bonds indicating the hetero-aromatic nature of the compound (region I). These data in the FT-IR spectrum support the proposed structure of Form A of ponatinib hydrochloride.
Experiments to determine the purity of Form A were carried out. With reference to
Form HCl2 was obtained from a solubility assessment in TFE/water and it was converted to form HCl2b one day after storage of the measuring plate at ambient conditions, as confirmed by the XRPD re-measurement of the specific sample. HCl2 was also obtained in the experiments performed in Phase 2 described herein from aqueous solvent systems (water and MeOH/water) and it also converted to form HCl2b upon storage at ambient conditions (see overview in
Form B was analyzed by X-ray powder diffraction (XRPD).
Experiments to determine the purity of Form B were carried out. With reference to
Form C is a hydrated form. Form HCl2b was initially obtained from the solubility assessment experiments, either by conversion of Form B, over a number of days under ambient conditions or directly from TFE/water solvent mixtures. Form C was also obtained in the Phase 2 experiments from aqueous solvent systems (water and water/DMSO) (see overview in
Form C was analyzed by X-ray powder diffraction (XRPD).
With reference to
Experiments to determine the purity of Form C were carried out. With reference to
HCl3-class was mostly obtained from aromatic solvents, as can be seen in the overview in
Based on the thermal analyses, the sample representative of the Form D was assigned as a toluene solvated form (API:toluene 1:0.5). The form desolvated at 199.5° C., recrystallized and a second melting was observed at 257.6° C. (most likely corresponding to the melting point of Form A). HCl3-class is mildly hygroscopic, with 2.5% water mass uptake at 95% RH. The process was reversible regarding to physical stability and sample appearance.
HCl3-class sample was found to be physically stable after 8 months storage under ambient conditions and following the DVS cycle. However, HCl3-class sample converted to HCl1 after 1 week in the humidity chamber (40° C./75% RH).
Form D was analyzed by X-ray powder diffraction (XRPD).
With reference to
With reference to
With reference to
Experiments to determine the purity of Form D (PSM1) were carried out. With reference to
HCl4 was only obtained as a mixture with Form A from a grinding experiment with hexafluorobenzene (see overview in
Form E of ponatinib hydrochloride was found not to be physically stable upon storage at ambient conditions. The mixture HCl1+HCl4 was re-measured by XRPD after 8 months of storage and it had converted to Form A.
Form HCl5 was obtained from one vapor diffusion onto solids experiment described here in butyl acetate (see overview in
A DVS experiment showed that HCl5-class is highly hygroscopic, with a 37% water mass adsorption. The material lost its crystallinity as indicated by the XRPD following the DVS experiment.
Form F was successfully scaled up at the 120 mg scale using the same conditions as those of the original experiment to identify the previously discovered polymorphs. Two scale-up experiments were performed and the corresponding XRPD patterns indicated forms isostructural to HCl5. These isostructural forms together with HCl5 and HCl5b were designated HCl5-class or Form F.
With reference to
A cycling DSC experiment showed that upon desolvation, HCl5-class converted to a form designated “HCl5-desolvate”, which melted at circa 210° C.
With reference to
With reference to
Experiments to determine the purity of Form F (VDS2) were carried out. With reference to
Form G of ponatinib hydrochloride was obtained by conversion of HCl5, upon drying for 3 days under full vacuum. HCl5b form was found to be physically stable after 8 months storage under ambient conditions.
Characterization data for Form G is provided herein in the context of Form F.
HCl6 was obtained from two experiments; vapor into solution and vapor onto solids, in MeOH/water and MeOH solvent systems, respectively (see overview in
HCl6-class was characterized by DSC, cycling-DSC, TGMS, FTIR, HPLC and DVS. The physical stability under short-term storage conditions (i.e. one week at 40° C. and 75% RH) was investigated. Form H samples were physically stable, as assessed by XRPD, after 8 months storage under ambient conditions. After 1 week in the humidity chamber (40° C./75% RH), the material was still HCl6-class, however with a slightly different XRPD.
With reference to
With reference to
With reference to
Experiments to determine the purity of Form H (VDS4) were carried out. With reference to
Characteristics of Form I (HCl6 Desolvate): A cycling DSC experiment conducted in connection with the experiments for Form H showed that upon desolvation, HCl6-class converted to a form designated “HCl6-desolvate”, which melted at circa 220° C.
Form J is a pentahydrate of ponatinib HCl and was discovered in the context of a single crystal analysis. Form J is the most stable hydrated structure identified, as competitive slurries in water between the trihydrate and pentahydrate showed.
Single crystals of suitable size were obtained in the vapor diffusion experiment performed with the solvent mixture methanol/water 20:80 and n-butyl acetate as anti-solvent. One parallelepiped single crystal of approximate size 0.45×0.25×0.12 mm was collected from the crystallization vial and mounted on a glass fiber. The crystallographic data (collected up to 0=27.5°) are listed in Table 4.
The asymmetric unit comprises the cation, the chloride anion and five water molecules (pentahydrate). The water molecules are connected via hydrogen bonding (H-Bonds) with the anion, the cation and neighboring water molecules.
The important consequence of the present H-Bonds arrangement is the fact that in this crystal both charged atoms (i.e. the protonated nitrogen from the API and the chloride anion) are bridged/separated by several molecules of water.
Form K was discovered in the context of a single crystal analysis. The single crystals were grown in the slow evaporation experiment conducted with TFE/H2O mixture 50:50. One block-like single crystal of approximate size 0.40×0.30×0.25 mm was analyzed. Although the crystal was large, it diffracted quite poorly, which is an indication of partial disorder in the structure. Therefore the measurement was recorded only up to θ=25°. The crystallographic parameters are listed in Table 5.
The structure of the mixed TFE solvated/hydrated form comprises the cation, the chloride anion and two neutral entities: the trifluoroethanol and the water molecules. In this structure, although water molecules are involved in the H-bonding they do not separate the charged atoms (contrary to the pentahydrated and trihydrated forms. The TFE and water molecules acted only as donors in the hydrogen bonding network. In particular for the water molecules, only one of the hydrogen atoms acts as donor, which could be responsible for the disorder of the water molecules and the fact that the ratio of the water molecules compared to the API molecules is not stoichiometric.
In addition, amorphous ponatinib hydrochloride has a unique melting temperature as compared to Form A of amorphous ponatinib hydrochloride.
Unique and distinct physical properties of amorphous ponatinib hydrochloride and Form A of ponatinib hydrochloride do not seem to be attributed to purity of the respective materials. In the case of amorphous ponatinib hydrochloride, the material was determined by HPLC to have a purity of 99.7877% (area percent) (see
Initial efforts to discover polymorphic forms of ponatinib hydrochloride were divided into two phases. Phase 1 included starting-material characterization, feasibility testing and solubility studies to provide data for the solvent selection for Phase 2. Phase 2 included 192 polymorph screening experiments at milliliter (ml) scale. These initial efforts led to the discovery of eight polymorphic forms, Form A, Form B, Form C, Form D, Form E, Form F, Form G and Form H.
Approximately 24 grams of the compound ponatinib hydrochloride was provided as a light yellow solid. This starting material was characterized by XRPD, digital imaging, DSC, TGMS and HPLC. The starting material, 3-(imidazo[1,2-b]pyridazin-3-ylethynyl)-4-methyl-N-{4-[(4-methylpiperazin-1-yl)methyl]-3-(trifluoromethyl)phenyl}benzamide mono hydrochloride, is provided as a crystalline material (designated HCl) and its chemical purity was assessed by HPLC as 99.8%. TGA and TGMS analyses showed 0.7% of mass loss (residual ethanol) in the temperature interval 25° C.-240° C. prior to the thermal decomposition process. DSC analysis showed an endothermic event with Tpeak=264.8° C., probably related to melting and/or decomposition of the compound, 3-(imidazo[1,2-b]pyridazin-3-ylethynyl)-4-methyl-N-{4-[(4-methylpiperazin-1-yl)methyl]-3-(trifluoromethyl)phenyl}benzamide mono hydrochloride.
Quantitative solubility testing was performed on ponatinib hydrochloride starting material, employing a set of 20 solvents. Slurries were prepared with an equilibration time of 24 hours after which the slurries were filtrated. The solubility was determined from the saturated solutions by HPLC. The residual solids were characterized by XRPD. The results are summarized in Table 6.
1The solid form obtained from the slurry was assessed based on the XRPD analysis.
2Under Range, lower then detection limit, the concentration is lower than 0.22 mg/ml
3Over Range, the material was dissolved, the concentration is higher then 200 mg/ml.
4Amorphous
In 19 of the experiments shown in Table 6, the materials analyzed following the solubility assessments in 19 different solvents appeared to be the same form as the starting material designated form HCl. In the experiment QSA13 performed in 2,2,2-trifluoroethanol, the material dissolved completely at the selected concentration and the sample obtained after evaporation of the solvent resulted in amorphous material. The solids from two slurries in water (QSA12 and QSA21) resulted in two different forms, Form HCl2 and Form HCl2b, respectively. After a few days stored at ambient conditions, the form HCl2 converted to Form HCl2b and it could therefore not be further characterized. Upon further characterization, the Form HCl2b was determined to be a hydrated form (ratio API/water 1:1.4).
Feasibility tests were performed to attempt to obtain amorphous starting material that could be employed in some crystallization techniques of the Phase 2 portion of the study. Two techniques were employed i.e. grinding and freeze-drying. The results are presented below.
Grinding. Two grinding experiments were performed with two different durations at a frequency of 30 Hz. After 60 minutes of grinding, the crystalline starting material converted to amorphous. After 120 min, the resulting material remained amorphous with a chemical purity of 99.6%.
Freeze-drying. Eight freeze-drying experiments were performed with 3-(imidazo[1,2-b]pyridazin-3-ylethynyl)-4-methyl-N-{4-[(4-methylpiperazin-1-yl)methyl]-3-(trifluoromethyl)phenyl}benzamide mono hydrochloride. These experiments are summarized in Table 7.
1Based on the TGMS results.
2Chemical purity determined by HPLC.
The solubility of compound ponatinib hydrochloride in tetrahydrofuran, 2-methyltetrahydrofuran and dichloromethane was too low to apply the freeze drying procedure in good conditions. With solvents such as methanol, 2,2,2-trifluoroethanol (TFE) and TFE/water mixtures, amorphous material was obtained. In the samples obtained from neat TFE or with high TFE content in the solvent mixtures, 11% of residual solvent was detected in the dried powders (according to the TGMS results). The samples obtained from methanol and TFE/water 50:50 contained less residual solvent only 0.9% and 1.5%, respectively. The amount of residual solvent in the amorphous material produced from TFE/water 50:50 could be reduced to below 1% after extra drying for 24 hours. For both amorphous samples obtained from methanol and TFE/water 50:50, the chemical purity was assessed to be 99.8% by HPLC. Because creeping was observed in the freeze-drying experiment with methanol, the procedure using TFE/water 50:50 was selected to be used to produce the amorphous ponatinib hydrochloride to be used in the cooling-evaporation crystallizations and vapor diffusion onto solids experiments of Phase 2.
The polymorph screening experiments for ponatinib hydrochloride were carried out at milliliter (ml) scale using 192 different conditions in which six different crystallization procedures were applied: (1) cooling-evaporation; (2) anti-solvent addition; (3) grinding; (4) slurry; (5) vapor diffusion into solutions; and (6) vapor diffusion onto solids. After the screening experiments were completed, the materials were collected and analyzed by XRPD and digital imaging.
Cooling-Evaporative Crystallization Experiments. The 36 cooling-evaporative experiments shown at Table 8 at ml scale were performed in 1.8 ml vials, employing 36 different solvents and solvent mixtures and 1 concentration. In each vial, 25 mg of amorphous ponatinib hydrochloride was weighed. Then the screening solvent was added to reach a concentration of circa 60 mg/ml. The vials, also containing a magnetic stirring bar, were closed and placed in an Avantium Crystal16 to undergo a temperature profile, (as described in Table 9 below). The mixtures were cooled to 5° C. and held at that temperature for 48 hours before placing the vials under vacuum. The solvents were evaporated for several days at 200 mbar or 10 mbar and analyzed by XRPD and digital imaging.
Crash-crystallization with anti-solvent addition Experiments. For the crash-crystallization experiments, 36 different crystallization conditions were applied, using 1 solvent and 24 different anti-solvents (see Table 9). The anti-solvent addition experiments have been performed forwards. A stock solution was prepared, the concentration of ponatinib hydrochloride being that attained at saturation at ambient temperature after equilibration for 24 hours before filtering into 8 ml vials. To each of these vials a different anti-solvent was added, using a solvent to anti-solvent ratio of 1:0.25. Because no precipitation occurred, this ratio was increased to 1:4 with a waiting time of 60 minutes between each addition. As no precipitation occurred yet, the solvents were completely evaporated under vacuum at room temperature. After evaporation, the experiments resulted to have no yield.
Grinding Experiments. The drop-grinding technique uses a small amount of solvent added to the material 3-(imidazo[1,2-b]pyridazin-3-ylethynyl)-4-methyl-N-{4-[(4-methylpiperazin-1-yl)methyl]-3-(trifluoromethyl)phenyl}benzamide mono hydrochloride, which is grinded in a stainless steel grinder jar with 2 stainless steel grinding balls. In this manner, the effect of 24 different solvents (see Table 10) was investigated. Typically 30 mg of starting material was weighed in the grinding container and 10 μl of solvent was added to the container. The grinding experiments were performed at 30 Hz during 120 min. Each wet material was subsequently analyzed by XRPD and digital imaging.
Slurry Experiments. A total of 48 slurry experiments were performed with the compound ponatinib hydrochloride and 24 solvents at 10° C. and 30° C., for 2 weeks. Table 11 summarizes the experimental conditions. The experiments were carried out by stirring a suspension of the material in a solvent at a controlled temperature. At the end of the slurry time, the vials were centrifuged and solids and mother liquids separated. The solids were further dried under full vacuum at room temperature and analyzed by XRPD and digital imaging.
Vapor Diffusion Into Solutions. For the vapour diffusion experiments, saturated solutions of ponatinib hydrochloride were exposed to solvent vapours at room temperature for two weeks. A volume of saturated solution was transferred to an 8 ml vial which was left open and placed in a closed 40 ml vial with 2 ml of anti-solvent (see Table 12). After two weeks, the samples were checked for solid formation. The samples were dried under vacuum (200 mbar or 10 mbar) and resulted to have no yield. Based on the results, additional experiments were performed with 12 different crystallization conditions as described in the table, experiments ID VDL25-VDL36.
Vapor Diffusion Onto Solids. For the vapour diffusion experiments, amorphous ponatinib hydrochloride was exposed to solvent vapours at room temperature for two weeks. The 8 ml vials with the amorphous API were left open and placed in a closed 40 ml vial with 2 ml of anti-solvent (see Table 13). After two weeks, the solids were analyzed by XRPD and digital imaging. If the solids were liquefied by the vapours, the samples were dried under vacuum (200 mbar or 10 mbar) before they were analyzed by XRPD and digital imaging.
In the crystallization experiments during these initial efforts, XRPD analysis of the dry (and if applicable wet) samples obtained revealed the presence of seven additional polymorphic forms in addition to amorphous materials and the starting material, Form A. The seven forms are designated HCl2, HCl2b, HCl3-class, HCl5, HCL5b, HCl6-class and the mixture HCl1+HCl4.
The occurrence of the different forms obtained in Phase 2 of these initial efforts is presented in
aOcc: the total occurrence included 216 experiments carried out in Phase 2 for which 39 samples were analyzed additionally wet or the mother liquor was evaporated and analyzed giving a total of 254 materials characterized. For example, “(3, 1.2%)” correspond to 3 occurrences of the form out of 254 measurements, giving a percentage of 1.2%. For 62 out of the 254 measurements (9%), the product yield or the scattering intensity of some products was too low to identify the solid form, or the materials were wet.
bCrystallization modes: cooling-evaporative (PSM), crash crystallization with anti-solvent addition (AS), grinding (GRP), slurry (SLP), vapour diffusion onto solid (VDS) and vapour diffusion into solution (VDL). Freeze-drying (FD) was used to produce amorphous material (see Phase 1 experiments). QSA (quantitative solubility experiment), see Phase I experiments.
cSolvation state assessed from the TGMS results.
dEndotherms assessed from the DSC results.
eChemical purity assessed from HPLC results.
fNot determined in this experiment.
gStructure determined by single crystal analysis.
The polymorphic forms identified in these Phase 1 and Phase 2 experiments and shown in
The classes of isomorphic solvates were designated by a number (HCl3-Class) or a number-letter combination (for example HCl2 and HCl2b). The class of isomorphic solvates/hydrates designated by a letter-number combination indicates that few sub-classes were observed for this class in the experiment (example HCl2 and HCl2b). When more than three sub-classes could be identified within the class, all XRPD patterns corresponding to a class of isomorphic solvates/hydrates were regrouped under one number (example HCl3-Class).
The isomorphic solvates within a certain class or between classes designated with the same number showed a higher degree of similarity of their XRPD patterns than in the case of the classes of isomorphic solvates designated with different numbers. For these different classes of isomorphic hydrates/solvates, the larger differences in the XRPD patterns reflect that the crystal structure packing is significantly different.
In some XRPD patterns, one or two additional peaks were observed compared to the identified forms. Since these peaks could not be assigned clearly to the known forms, they were indicated as “plus peaks”.
Follow on efforts were undertaken to analyze single crystals of 3-(imidazo[1,2-b]pyridazin-3-ylethynyl)-4-methyl-N-{4-[(4-methylpiperazin-1-yl)methyl]-3-(trifluoromethyl)phenyl}benzamide mono hydrochloride. Such efforts led to the discovery of five different pseudo polymorphs with two of these additional polymorphic forms being previously undiscovered. These two newly discovered polymorphic forms are designated herein as HCl7 (also referred to herein as “Form J”) and HCl 8 (also referred to herein as “Form K”). In these later experiments, three different crystallization techniques were used to grow single crystals of suitable size for analysis: (1) slow evaporation of crystallization solvent; (2) diffusion of anti-solvent into a solution of 3-(imidazo[1,2-b]pyridazin-3-ylethynyl)-4-methyl-N-{4-[(4-methylpiperazin-1-yl)methyl]-3-(trifluoromethyl)phenyl}benzamide mono hydrochloride; and (3) temperature controlled crystallization. In total, 54 crystallization experiments were performed in these later experiments to attempt to grow single crystals of the hydrated form of ponatinib hydrochloride salt for structure determination.
With regard to temperature controlled crystallization, 24 experiments were prepared with mixtures of alcohols and water (see Table 15). For each experiment, 10 mg of ponatinib hydrochloride was used. The mixtures of API and solvents were heated fast up to 80° C. and slowly cooled to room temperature (0.1° C./min).
With regard to vapor diffusion into solution, 25 experiments were performed. For each experiment, 10 mg of ponatinib hydrochloride was dissolved in 1 ml of mixture of TFE/Water (10:90) or MeOH/Water (30:70). Each solution was placed in a 6 ml vial, which was inserted in a 20 ml vial containing 3 ml of anti-solvent. The vials were kept at room temperature for 2-4 weeks. The details are reported in Table 16.
With regard to slow evaporation of solvents, 10 mg of ponatinib hydrochloride was placed in an 8 ml vial and 2 ml of solvent (mixture of solvents) was added. In those cases in which the solids did not dissolve, the vial was heated to 90° C. Subsequently, the mixture was left to cool slowly to room temperature (see Table 17). For the last entry in Table 17, Exp. 53, the material had not completely dissolved after having been held several hours at 90° C.
Each of the polymorphic forms disclosed herein are made from specific crystallization/solvent modes using ponatinib HCl as the starting material. While the synthesis of ponatinib HCl has been described previously (e.g., WO 2007/075869 and WO 2011/053938), the following synthesis of ponatinib HCl is provided at Example 6.
Form A is a crystalline, anhydrous solid that has been reproducibly obtained from a range of solvents. Form HCl-1 is intrinsically chemically stable, which directly correlates to the thermodynamic stability of the HCl 1 form. Form HCl-1 is stable to thermal, pressure, and humidity stress as well as exposure to some solvent vapors, and is thermodynamically stable. Numerous studies have been conducted to confirm its stability in both the formulated (tablets) and unformulated (drug substance) state. The results of such studies are provided in Table 18 below:
Form HCl-1 is stable to thermal, pressure, and humidity stress as well as exposure to some solvent vapors, and is the most thermodynamically stable solid form isolated to date.
Experiments were carried out to test the physical stability of the crystalline Form HCl1 as follows:
The crystalline Form HCl1 and a physical mixture of HCl1 and amorphous material 50:50 were exposed to ethanol vapour for two weeks (see vapour diffusion experiments). Tablets were prepared by subjecting the crystalline Form HCl1 to a pressure of 50 and 100 kN/cm2 (or 4 and 8 ton/cm2) for 10 sec. Form A was stored in capsules for up to 17 months at ambient conditions. These samples were analyzed by high resolution XRPD.
The results obtained are summarized in Table 19 and the XRPD measurements and digital images were obtained. They showed that within the stress conditions applied, the polymorphic Form HCl1 remained unchanged, confirming its good physical stability.
Samples of the 8 solid forms of HCl salt were chosen to study their physical stability. Two samples representative of each relevant polymorphic forms of the HCl salt obtained were selected. Each sample was re-analyzed by XRPD. The physical stability of the forms after being stored at ambient conditions for 8 months. The results are summarized below:
HCl1, HCl2b, HCl3-Class, HCl5b and HCl6-Class are physically stable under the investigated conditions;
HCl2 converted to HCl2b (this conversion already occurred after storage of the sample under ambient conditions for 1 day);
HCl5 converted to HCl5b (this conversion already occurred following drying for 3 days under full vacuum);
The mixture HCl1+HCl4 converted to HCl1 after 8 months at ambient conditions.
aStarting material (SM): Form HCl1 or amorphous material (Am) obtained by freeze-drying.
bAs classified by XRPD after completion of the crystallization experiment.
cCrystallization modes: cooling-evaporative (PSM), crash crystallization with anti-solvent addition (AS), grinding (GRP), slurry (SLP), vapour diffusion onto solid (VDS) and vapour diffusion into solution (VDL). QSA (quantitative solubility experiment).
dSolvation state assessed from the TGMS results.
eNd = not determined.
fHCl2 and HCl5 converted to HCl2b and HCl5b after respectively storage at room temperature for a 1 day or drying under vacuum for 3 days.
Form A of ponatinib HCl is formed as a crystalline material by addition of a solution of HCl (1.0 equivalents) in ethanol to an ethanolic solution of the ponatinib free base. The drug substance, ponatinib HCl, s crystallized in the last step of the drug substance synthetic process by addition of seed crystals which results in a very consistent and characteristic particle size and range for the drug substance. Ethanol content in the last 10 multi-kilogram scale batches of ponatinib HCl in the HCl-1 form ranged from 0.8-1.2%.
No evidence of ethanol or water was found in the HCl-1 form; hence the Form A is an anhydrate. In addition, the crystal packing of the HCl-1 form does not contain voids capable of accommodating ethanol or other small organic molecules. Additional studies to investigate the ethanol content and the removal of ethanol from ponatinib HCl during drying have indicated that the ethanol appears to be associated with the surface of the crystals in Form A of ponatinib HCl.
Form HCl-1 is characterized by the consistent presence of residual ethanol in all batches of drug substance at a level of approximately 1% by weight. Crystallographic studies and other studies have shown that residual ethanol is present (trapped) on the surface of the crystals, and is not part of the crystalline unit cell, and that HCl-1 is not an ethanol solvate or channel solvate. Ethanol levels in the last ten multi-kilogram scale drug substance batches have ranged from 0.8 to 1.2%.
The preparation of ponatinib free base starting material (AP23534) is shown and discussed below in the synthesis section of the disclosure (see Scheme 1). Preparation of amorphous free base is discussed in the section of the disclosure entitled “Feasibility Study on Ponatinib Free Base Compound” set out herein below.
Through XRPD analysis, a total of eleven polymorphic forms of ponatinib were discovered, including anhydrate, and hydrate, solvate and isomorphic hydrate/solvate forms, beginning from ponatinib free base starting material. The eleven new polymorphic forms are referred to herein as: Form A, Form B (or B-Class forms), Form C, Form D, Form E (or E-Class), Form F, Form G, Form H (or H-Class forms), Form I, Form J and Form K.
The anhydrate Form A (melting point ˜200° C.) was the predominant crystalline form found in the screening. Form B includes four isomorphic solvates, namely a 1:1 dioxane solvate, a 1:1 perfluorobenzene solvate, a 1:0.4 2-methylTHF solvate, and a 1:1 cyclohexanone solvate. Form E includes chloroform and dichloromethane isomorphic solvates. Form D is a solvated form (e.g. DMA). Form F is a monohydrated form. Form H includes two isomorphic solvates, a 1:0.6 1-propanol solvate and a 1:0.93 2-methoxyethanol solvate.
The assignment of the forms obtained in the Phase 3 and Phase 4 experiments was primarily based on the XRPD analysis. From this, it could be observed that some patterns had similarities in the general fingerprint of the XRPD pattern but showed some small differences such as peaks shifting and/or small additional peaks. These types of patterns were clustered as a class of patterns (e.g. B-Class). Based on the XRPD, similarity between the XRPD patterns within a class can indicate that these solid forms are isomorphic hydrates/solvates (similar crystal packing but slightly different unit cell parameters caused by the incorporation of the different solvents and water in the crystal structure). The classes of isomorphic solvates were designated by a letter (B-Class).
In some XRPD patterns, one or more additional peaks were observed compared to various identified forms. Since these peaks could not always be assigned clearly to the known forms, they were indicated as “plus peaks” where appropriate, (e.g. “Form F plus peaks”).
The polymorph screen for ponatinib comprised six types of crystallization methods, carried out on millimeter scale. The methods included: crash-crystallization with anti-solvent addition; grinding; slurry experiments; vapor diffusion into solution; cooling-evaporative crystallization; and vapor diffusion onto solids. These methods were discussed above for preparation of the various ponatinib hydrochloride polymorphs. Any differences in the methods when applied to the ponatinib free base polymorphs will be discussed below.
The crystal structures of Form A and the two Form B solvates were determined by single crystal X-ray data analysis. These studies showed the conformation adopted by Form A in the crystal structure and the solvent inclusion in the two Form B solvates.
In general, these various crystalline forms of ponatinib disclosed herein have physical properties (such as high stability, etc.) that are advantageous for the commercial preparation of solid dosage forms as compared to amorphous ponatinib. The distinction between crystalline ponatinib and amorphous ponatinib can be readily seen with the same type of physical chemical data (e.g., DSC, XRPD, thermal analysis) that is used to distinguish the individual crystalline forms of ponatinib disclosed herein.
With reference to
With reference to the foregoing methodologies used in assessing the ponatinib hydrochloride polymorphs, the polymorphs of 3-(imidazo[1,2-b]pyridazin-3-ylethynyl)-4-methyl-N-{4-[(4-methylpiperazin-1-yl)methyl]-3-(trifluoromethyl)phenyl}benzamide free base are discussed below.
The anhydrate Form A (same crystalline form as the starting material) was the predominant crystalline form discovered in screening. The chemical structure of ponatinib Form A has been unambiguously established by single crystal X-ray crystallography. The observed solid form of ponatinib is the anhydrous crystalline solid Form A.
The crystallographic data for the anhydrate Form A (collected up to θ=26°) are listed in Table 21.
In the XRPD patterns shown in
With reference to
Characteristics of Ponatinib/1,4-Dioxane 1:1 Solvated Form B
Single-crystal X-ray diffraction analysis was employed to determine the crystal structure of the 1:1 1,4-dioxane solvated Form B.
The crystallographic data for the 1:1 1,4-dioxane solvated Form B (collected up to θ=27.4°) are listed in Table 22.
In the XRPD pattern shown in
Characteristics of Ponatinib/Perfluorobenzene 1:1 Solvated Form B
Single-crystal X-ray diffraction analysis was employed to determine the crystal structure of the 1:1 perfluorobenzene solvated Form B.
The crystallographic data for the 1:1 perfluorobenzene solvated Form B (collected up to θ=27.6°) are listed in Table 23.
In the XRPD patterns shown in
Characteristics of Ponatinib/Cyclohexanone 1:1 Solvated Form B and Ponatinib/2-methylTHF 1:0.4 Solvated Form B.
In the upper XRPD pattern shown in
In the middle XRPD pattern shown in
TGMS data for the B-Class 1:1 ponatinib/cyclohexanone solvate (QSA7.1) showed mass losses of 14.8% (cyclohexanone and water) and 0.2% (cyclohexanone) occurring within the temperature intervals of 50-160° C. and 160-210° C., respectively. The ponatinib/cyclohexanone ratio was assessed from the TGMS data to be about 1.0/0.96.
Experiments to determine the purity of the B-Class 1:1 ponatinib/cyclohexanone solvate (QSA7.1) were performed using HPLC. From HPLC it was determined that the purity of the B-Class 1:1 ponatinib/cyclohexanone solvate (QSA7.1) is 99.7460% (area percent).
TGMS data for the B-Class 1:0.4 ponatinib/2-methylTHF solvate (GEN8.1) showed mass losses of 3.1% (2-methylTHF), 1.9% and 1.0% (2-methylTHF) occurring within the temperature intervals of 40-90° C., 90-165° C. and 165-215° C., respectively. The ponatinib/2-methylTHF ratio was assessed from the TGMS data to be about 1.0/0.4.
Experiments to determine the purity of the B-Class 1:0.4 ponatinib/2-methylTHF solvate (GEN8.1) were performed using HPLC. From HPLC it was determined that the purity of the B-Class 1:0.4 ponatinib/2-methylTHF solvate (GEN8.1) is 99.5939% (area percent).
The low crystalline Form C can be obtained in the slurry experiments from crystalline Form A in methanol as the solvent. Form C was found to contain solvated methanol with the ratio of Ponatinib/methanol of about 1:0.2.
TGMS data for Form C (GEN3.1) showed a mass loss of 1.3% (methanol) occurring within the temperature interval of 40-150° C. The ponatinib/methanol ratio was assessed from the TGMS data to be about 1.0/0.2.
Form C was analyzed by X-ray powder diffraction (XRPD).
In the upper XRPD pattern shown in
Experiments to determine the purity of Form C (GEN3.1) were performed using HPLC. From HPLC it was determined that the purity of Form C of ponatinib is 99.5725% (area percent).
Form D may be obtained from crystalline Form A by crash-crystallization in N,N-dimethylacetamide (DMA) by anti-solvent addition. Produced in this manner, Form D was found to be a DMA solvate with the ratio of Ponatinib/DMA of about 1:1.
TGMS data for Form D (GEN5.1R1) showed a mass loss of 13.8% (N,N-dimethylaceamide) occurring within the temperature interval of 40-140° C. The ponatinib/DMA ratio was assessed from the TGMS data to be about 1.0/0.98.
Form D was analyzed by X-ray powder diffraction (XRPD).
In the middle XRPD pattern shown in
Experiments to determine the purity of Form D were performed using HPLC. From HPLC it was determined that the purity of Form D of ponatinib is 99.5056% (area percent).
The E-Class solvents are prepared from either crystalline Form A or low crystalline Form C in slurry and solubility experiments, using solvents such as tetrahydrofuran (THF), chloroform and dichloromethane (DCM), or by vapor diffusion onto solids.
Based on thermal analyses, one sample representative of Form E was assigned as a ponatinib/tetrahydrofuran (THF) 1:1 solvated form. Another sample representative of Form E appears to be a chloroform solvate, but this material was not characterized further other than by XRPD.
TGMS data for E-Class ponatinib/THF 1:1 solvate (GEN7.1) showed a mass loss of 11.7% (THF) occurring within the temperature interval of 40-130° C. The ponatinib/THF ratio was assessed from the TGMS data to be about 1.0/0.98.
The two above mentioned Class-E polymorphs were analyzed by X-ray powder diffraction (XRPD).
In the upper XRPD pattern shown in
In the middle XRPD pattern shown in
Experiments to determine the purity of E-Class ponatinib/THF 1:1 solvate (GEN7.1) were performed using HPLC. From HPLC it was determined that the purity of E-Class ponatinib/THF 1:1 solvate (GEN7.1) of ponatinib is 99.5120% (area percent).
Form F was formed from Form A in specific experimental conditions such as in the presence of polar solvents. Analysis of Form F by TGMS showed that Form F loses 3.3% of water in the first temperature range of 25-140° C. From these results it could be concluded that the first endotherm event observed corresponded to a dehydration process and that Form F was a hydrated form, e.g. a 1:1 hydrate with water.
From the screening experiments, selected samples of pure Form F (6 samples) and mixtures of Forms A and F (6 samples) were re-analyzed by XRPD after storage at ambient temperature for 4-months. The results are shown in Table 24 below.
aAs classified by XRPD after completion of the crystallization experiments.
bCrystallization modes: cooling-evaporative (PSM), crash crystallization with anti-solvent addition (AS), slurry (SLP), vapour diffusion onto solid (VDS) and vapour diffusion into solution(VDL).
cFrom the screen, some experiments were selected to be remeasured by XRPD after storage for 4 months at ambient temperature.
dAs classified by XRPD after storage of the samples for 4 months at ambient conditions.
The results in Table 24 show that in most of the cases the polymorphic forms remained unchanged. The results obtained in the crash crystallization with anti-solvent experiment (2-methoxyethanol/water) showed that when the sample was harvested wet, the Form F material obtained converted to Form A after 4 months. Also in the anti-solvent addition experiment with acetone/water, Form F converted to a mixture of Forms A and F after 4 months.
The melting point of Form F (AS16.2) was observed at about 189° C.
As mentioned, TGMS data for Form F (AS16.2) showed a mass loss of 3.3% (water) occurring within the temperature interval of 25-140° C. The ponatinib/water ratio was assessed from the TGMS data to be about 1.0/1.01 for Form F.
Form F (SLP10.1) was analyzed by X-ray powder diffraction (XRPD). In
In the XRPD pattern shown as the pattern fifth from the top in
Characteristics of Ponatinib/1-Propanol 1:1 Solvated Form H
Solid recovered from a dissolution experiment with 1-propanol was determined to be a 1-propanol solvate of Form H.
The DSC curve obtained for H-Class ponatinib/1-propanol solvate (SAS35) showed endothermic events appearing at Tpeak of about 93° C. and Tpeak of about 192° C.
The TGMS data for H-Class ponatinib/1-propanol solvate (SAS35) showed a mass loss of 9.2% (1-propanol) occurring within the temperature interval of 25-120° C. The ponatinib/1-propanol ratio was assessed from the TGMS data to be about 1.0/0.9 for H-Class ponatinib/1-propanol solvate (SAS35). Another sample, (SAS30) showed a mass loss corresponding to a 1:0.6 solvate, but this sample was later determined to have partially converted back to crystalline anhydrate Form A, thus reducing the overall solvent loss observed for the bulk sample.
H-Class solvate (SAS35) was analyzed by X-ray powder diffraction (XRPD) wherein at least one or all of the following peaks in degrees two theta (2θ) appeared: 6.1; 6.8; 10.0; 12.0; 13.2; 13.5; 16.0; 16.5; 16.0; 16.5; 18.0; 19.0; 19.5; 20.4; 21.0; 22.5; 25.0; 25.5; 26.2; 27.0; and 27.5. In certain embodiments, Form H is characterized by a XRPD pattern comprising one or more of the following peaks two theta (2θ): 12.0; 13.2; 13.5; 18.0; 25.0 and 25.5. In certain embodiments, the XRPD pattern of Form H shows two peaks, three peaks, four peaks or five peaks selected from those given above.
Characteristics of Ponatinib/2-Methoxyethanol 1:1 Solvated Form H
Ponatinib free base can form isomorphic solvates of Form H in other alcohols. A 2-methoxyethanol solvate was obtained by a vapor diffusion into liquid procedure, beginning with Form A as the starting material and using 2-methoxyethanol as solvent. The purity of this form was assessed to be 98.0%. TGMS confirmed it to be the 1:0.93 ponatinib/2-methoxyethanol solvate, which desolvated at about 96° C. After desolvation, a melting point of about 198.8° C. was observed in the DSC, which corresponds closely to the melting point of Form A.
The DVS experiment showed a loss of weight during desorption of about 3.6%, which was not regained during sorption to 45% RH. XRPD analysis at the end of the DVS experiments indicated no physical change. While possible that partial desolvation occurred, the process did not cause the crystal structure to collapse (as indicated by the TG-MS about 12% weight loss is observed during the desolvation).
Form H, however, converted to Form A during 10 months of storage under ambient conditions, and also after one week in a humidity chamber at accelerated stress conditions (40° C., 75% RH).
The DVS experiment for Form H (VLD1, dried solid from stock) showed a loss of weight of about 11.7% (2-methoxyethanol) in the temperature range of 25-120° C. From these results, the first endotherm event observed corresponded to a desolvation process and that Form H (VLD1, dried solid from stock) was a 1:0.93 ponatinib/2-methoxyethanol solvate.
In the XRPD pattern shown as Plot 5 in
Experiments to determine the purity of Form H (VLD1 dried solid from stock) were performed using HPLC. From HPLC it was determined that the purity of Form H of ponatinib (VLD1 dried solid from stock) is 98.0464% (area percent).
The low crystalline Form I was obtained by a freeze-drying technique in dichloromethane (DCM).
Based on thermal analyses, Form I (GEN9.1) contains a slight level of solvated DCM, corresponding to a ponatinib/DCM ratio of about 1:0.03.
TGMS data for Form I (GEN9.1) showed a mass loss of 0.5% (DCM) occurring within the temperature interval of 40-175° C. (slightly solvated). The ponatinib/DCM ratio was assessed from the TGMS data to be about 1.0/0.03.
The Form I (GEN9.1) was analyzed by X-ray powder diffraction (XRPD).
In the upper XRPD pattern shown in
Experiments to determine the purity of Form I (GEN9.1) were performed using HPLC. From HPLC it was determined that the purity of Form I (GEN9.1) of ponatinib is 99.5802% (area percent).
Form J was obtained by a vapor diffusion onto solids method. The purity was assessed to 96.5%. The TGMS analysis (weight loss of 11.4% thiophene during the interval 25-130° C.) confirmed that Form J “low crystalline” is a 1:0.82 ponatinib/thiophine solvate, which desolvates at 83.7° C. After desolvation, a melting point event occurs at about 197.3° C., which may be the melting of Form A.
The DVS experiment showed a weight loss during desorption of about 1.3%. The weight appears not to be regained during the sorption phase, at least up to 45% relative humidity (RH), (mass uptake about 0.33%). The XRPD analysis at the end of the DVS experiments indicated that the material converted to Form A.
Low crystalline Form J also converted to Form A after 10 months of storage under ambient conditions, and after 1-week under stress conditions, (40° C., 75% RH).
Two samples of ponatinib Form J (designated VDS2 and VDS10 of screen S10010A) were analyzed by X-ray powder diffraction (XRPD).
In the XRPD Plots 7 and 8 shown in
Experiments to determine the purity of Form J (VDS2) were performed using HPLC. From HPLC it was determined that the purity of Form J (VDS2) of ponatinib is 96.4509% (area percent).
Solid Form K was found in sample SAS58 (MSZW experiment): 25 mg/mL in 1-propanol/acetonitrile 30/70. The TGMS thermogram showed negligible mass loss (<0.04% in the temperature interval 25-175° C.) prior to melting. From the SDTA signal, the melting point of Form K is 184° C.
The DSC curve obtained for ponatinib Form K showed an endothermic event appearing at Tpeak of about 184° C.
Ponatinib Form K was analyzed by X-ray powder diffraction (XRPD) wherein at least one or all of the following peaks in degrees two theta (2θ) appeared: 10.0; 11.0; 13.4; 14.6; 15.2; 16.0; 17.0; 17.5; 18.0; 19.6; 20.9; 22.1; 22.8; 24.1; 24.8; 26.5; 27.1; 28.5; and 30.5. In certain embodiments, Form K is characterized by a XRPD pattern comprising one or more of the following peaks two theta (2θ): 10.0; 11.0; 13.4; 14.6; 15.2; 16.0; 19.6; 20.9; 22.1; 22.8; 24.1; 24.8; and 26.5. In certain embodiments, Form K is characterized by a XRPD pattern comprising one or more of the following peaks two theta (2θ): 10.0; 11.0; 13.4; 14.6; 15.2; 19.6; 22.1; 22.8; and 24.1. In certain embodiments, the XRPD pattern of Form K shows two peaks, three peaks, four peaks or five peaks selected from those above.
Initial efforts to discover polymorphic forms of ponatinib were divided into two phases. Phase 3 involved starting-material characterization, feasibility testing and solubility study to provide data for the solvents selection for phase 4. Phase 4 involved 192 polymorph screening experiments at milliliter (ml) scale. These initial efforts led to the discovery of eleven polymorphic forms of ponatinib free base, Form A, Form B, Form C, Form D, Form E, Form F, Form G, Form H, Form I, Form J, and Form K.
The compound ponatinib free base was obtained by the synthesis discussed herein below, which is characterized by an amide coupling reaction of an amine subunit and a methyl ester subunit. Approximately 20 grams of the free base (combined from two batches, designated as F09-05575 and F09-05576) were obtained as a light yellow solid. This starting material was characterized by XRPD, digital imaging, DSC, TGMS and HPLC.
TGA and TGMS analyses showed mass loss in one single step for the batch F09-05575, (0.9% in the temperature interval of 25-210° C.) whereas a two-step mass loss was observed in batch F09-05576 (0.3% mass loss in the temperature interval of 25-120° C. and 0.9% in the interval 120-210° C.). The mass losses observed in both batches correspond to 2-methyltetrahydrofuran (as confirmed by the m/z ratio's observed in the MS data). The presence of this solvent in residual quantities could originate from the last synthesis steps of ponatinib free base compound.
Experiments to determine the purity of ponatinib free base compound were performed using HPLC. From HPLC it was determined that the purity of batch F09-05575 is 99.5166% (area percent), and the purity of batch F09-05576 is 99.6869% (area percent).
In various embodiments, alternative methods of preparing Form A gave samples of varying crystallinity.
Preparation 1
A M010578 sample from 180 g run ABL411057 (2-Me-THF, 1.1 equiv. of aniline, 1.6 equiv. of KOtBu) was crystallized from neat 1-propanol, followed by a trituration of the 1-PrOH moist product in neat acetonitrile to give Form A in 99.39 a % purity.
Preparation 2
Two samples from 180 g run ABL411060 (2-Me-THF, 26° C. IT, 1.1 equiv. of aniline, 1.6 equiv. of KOtBu) were obtained from a solution of M010578 in 1-PrOH obtained after solvent swap from 2-Me-THF to 1-PrOH. The 1-PrOH solution was split 9:1.
779.5 g (9 parts) of the above solution of M010578 in 1-PrOH were allowed to crystallize at ambient temperature overnight. After filtration, the moist filter cake was triturated in 160 g of acetonitrile at 40° C., filtered and dried (50° C., 3 mbar) to obtain 211.6 g of ponatinib free base Form A (99.87 a %).
260 g of acetonitrile were added to 86.6 g (1 part) of the above solution of M010578 in 1-PrOH. The suspension was filtered after 1 h, the filter cake washed with ACN/1-PrOH (3:1 v/v), and dried to obtain 25.6 g free base (99.27 a %). Crystallization and isolation from 1-propanol followed by a trituration in acetonitrile gave product of higher HPLC purity than isolation by precipitation from a mixture of ACN/1-PrOH.
Quantitative solubility testing was performed on ponatinib free base starting material, employing a set of 20 solvents. Slurries were prepared with an equilibration time of 24 hours after which the slurries were filtered. The solubility was determined from the saturated solutions by HPLC. The residual solids were characterized by XRPD. The results are summarized in Table 25 below.
1The solid form obtained from the slurry was assessed based on the XRPD analysis.
2Under Range, lower than detection limit, the concentration is lower than 0.21 mg/mL.
3Over Range, the material was dissolved, the concentration is higher than 200 mg/mL.
The materials obtained from in 19 out of 22 different solubility assessments were the same polymorph as the starting material free base, designated Form A. The solid from the slurry with cyclohexanone shows a different XRPD, which was designated the B-Class of forms. Form B was further characterized as four solvates, as discussed herein above.
Feasibility tests were performed to attempt to obtain amorphous free base material that could be employed in some crystallization techniques of Phase 4. Two techniques were employed, i.e., grinding and freeze-drying. The results are presented below.
Grinding. As summarized in Table 26 below, two grinding experiments were performed with two different durations at a frequency of 30 Hz. After 60 or 120 minutes of grinding, the material remained crystalline, (Form A).
Freeze-drying. Eight freeze-drying experiments were performed with ponatinib free base compound. These experiments are summarized in Table 27 below.
1Based on the TGMS results;
2Chemical purity determined by HPLC.
With solvents such as 2,2,2-trifluoroethanol (TFE) and TFE/water mixtures, amorphous material was obtained. In the experiments carried out in 2-methyltetrahydrofuran, DMA/water 90:10 and THF, three new crystalline forms were observed and were designated B-Class, D and E-Class. The B-Class and E-Class of forms were also observed in the screen Phase 4, for which the results suggested that they are isomorphic structures. In the remaining experiments performed in methanol and dichloromethane, two low crystalline materials were produced (Form C low crystalline and Form I low crystalline, respectively).
The new crystalline forms were further analyzed by DSC, TGMS and HPLC to determine their characteristics. Form D and Form E were identified as solvates (1:1 API/DMA and 1:1 API/THF, respectively).
The low crystalline materials obtained from methanol (C low crystalline) and dichloromethane (I low crystalline) had a limited amount of residual solvent (1.3% in the temperature interval 40° C.-150° C. and 0.5% in the interval 40° C.-175° C., respectively).
Since the freeze-drying procedure in methanol was not optimal to produce low crystalline material, the procedure in dichloromethane was selected to produce this material to be used in the cooling/evaporative crystallizations and vapour diffusion onto solids experiments of Phase 4.
Based on the results of the feasibility studies and the solubility behaviour of ponatinib free base, the solvents for the Phase 4 experiments were selected.
In order to to select the screening solvents and to determine the concentration range to be used in the screen, quantitative solubility testing was performed on the free base starting material batch F09-05575. This screen employed a set of 20 solvents. For each solvent, a standard 1.8 ml screw cap vial was charged with 40 mg of the starting material, 200 μl of the solvent and a magnetic stirring bar. The vials were then closed and equilibrated at 25° C. for 24 h while stirring. The resulting mixtures (slurries) were filtered (0.5 micron) and the isolated mother liquors diluted to two dilutions selected according to the calibration curve. Quantities of the API in the diluted solutions were determined via HPLC analysis (DAD). The calibration curve was obtained from two independently prepared stock solutions of the free base compound in 2,2,2-trifluoroethanol.
Subsequently to the solubility determination, the residual solvent was evaporated from each vial (slurry) under vacuum at ambient temperature. All of the resulting residues were analyzed by X-ray powder diffraction to assay for new crystalline forms.
The experimental conditions of the feasibility study on the free base compound are summarized in Table 28 below. Following the experiments, HPLC analysis was performed to determine the purity and thermal analysis to determine the thermal behaviour of the forms.
1Solvent content assessed by TGA;
2Purity assessed by HPLC
The polymorph screening experiments for the ponatinib free base compound were carried out at milliliter (ml) scale using 192 different conditions in which the following six different crystallization procedures were applied: cooling-evaporation, anti-solvent addition, grinding, slurry, vapor diffusion into solutions and vapor diffusion onto solids.
Cooling-Evaporative Crystallization Experiments
The 24 cooling-evaporative experiments at ml scale were performed in 8 ml vials, employing 24 different solvents and 1 concentration. In each vial, 25 mg of ponatinib free base was liquid dosed (with dichloromethane). The samples were freeze dried to obtain powdery low crystalline material. Then, the screening solvent was added to reach a concentration of circa 60 mg/ml, (see Table 29 below). The vials were closed and a temperature profile was obtained as described in Table 30 below. The mixtures were cooled to 5° C. and held at that temperature for 48 h before placing the vials under vacuum. The solvents were evaporated for several days at 200 mbar or 10 mbar and analyzed by XRPD and digital imaging.
Crash-Crystallization with Anti-Solvent Addition
For the crash-crystallization experiments, 48 different crystallization conditions were applied, using 23 different solvents and 18 different anti-solvents (see Table 31 below). For each solvent, a stock solution was prepared, the concentration of ponatinib free base in each case being that attained at saturation at ambient temperature after equilibration for 17 hours before filtering into a set of 8 ml vials. To each of these vials, a different anti-solvent was added, using a solvent to anti-solvent ratio of 1:0.25. In those cases where no precipitation occurred, this ratio was increased to 1:4 with a waiting time of 60 minutes between the additions. Solids precipitated in the waiting time between the anti-solvent additions were separated by centrifugation. If no solids were obtained, the solvents were completely evaporated under vacuum at room temperature. If solids were obtained, they were analysed by XRPD and digital imaging.
The drop-grinding technique uses a small amount of solvent added to the ponatinib free base material which is ground in a stainless steel grinder jar with 2 stainless steel grinding balls. In this manner, the effect of 24 different solvents (see Table 32 below) was investigated. Typically, 30 mg of starting material was ground and analyzed.
A total of 48 slurry experiments were performed with ponatinib free base, 24 solvents at each of 10° C. and 30° C., for 2 weeks. Table 33 below summarizes the experimental conditions. The experiments are carried out by stirring a suspension of the material in a solvent at a controlled temperature. At the end of the slurry time, the vials were centrifuged and solids and mother liquids separated. The solids were further dried underfill vacuum at room temperature and analyzed by XRPD and digital imaging.
Vapor Diffusion into Solutions
For the vapor diffusion experiments, saturated solutions of ponatinib free base were exposed to solvent vapors at room temperature for two weeks. A volume of saturated solution was transferred to an 8 ml vial which was left open and placed in a closed 40 ml vial with 2 ml of anti-solvent (see Table 34 below). After two weeks, the samples were checked on solid formation. If solids were present the liquid was separated from the solid. The samples were dried under vacuum (200 mbar or 10 mbar) before they were analyzed by XRPD and digital imaging.
Vapor-Diffusion onto Solids
For the vapor diffusion experiments, amorphous ponatinib free base was exposed to solvent vapors at room temperature for two weeks. The API was liquid dosed into 8 ml vials and then freeze dried. The 8 ml vials with the amorphous material were left open and placed in a closed 40 ml vial with 2 ml of anti solvent (see Table 35 below). After two weeks, the solids were analyzed by XRPD and digital imaging. If the solids were liquefied by the vapors, the samples were dried under vacuum (200 mbar or 10 mbar) before they were analyzed by XRPD and digital imaging.
The purpose of this study was to reproduce and further characterize solid forms of ponatinib that were identified in the studies discussed herein above. From this study, it was determined that Forms D (isomorphic solvates) and Form F (monohydrate) are physically stable for a period of at least 10 months at ambient conditions. Forms from the B-Class and E-Class, as well as Form G, H, I (low crystalline) and J (low crystalline), converted to Form A over a period of 10 months at ambient conditions.
Scale-up of Form H and J (low crystalline) were successful. Scale-up attempt of Form G resulted in Form A. The scale-up project was carried out in three phases as follows:
Phase 1: investigation of the physical stability by XRPD of the various forms obtained in the previous studies after storage at ambient conditions for 8-10 months;
Phase 2: scale-up of selected solid forms of ponatinib free base to 50-120 mg for further characterization; and
Phase 3: Determination of solvation state, thermal characteristics and physical stability of the material from phase 2.
Form D (isomorphic solvate) and Form F (monohydrate) are stable for the duration of the study. The isomorphic solvates of Form B-Class and Form E-Class all converted to Form A. Forms G, H, I (low crystalline), and J (low crystalline) all converted to Form A.
Forms G, H and J (low crystalline) were selected for scale-up trials. Experimental conditions for the scale-ups were taken from the polymorph screen disclosed herein. Forms H and J (low crystalline) were successfully scaled-up.
The solid forms that were scaled up in the previous phase and of which the form was confirmed by XRPD were further characterized by: DSC, TGMS, FTIR, HPLC and DVS. Form A resulting from the attempts to scale-up Form G was not further characterized. In addition the physical stability to accelerated ageing conditions (one week at 40° C. and 75% RH) was investigated.
The present disclosure provides pharmaceutical compositions that comprise a therapeutically effective amount of a crystalline form of ponatinib hydrochloride disclosed herein and at least one pharmaceutically acceptable carrier, vehicle or excipient. A unit dosage form of a pharmaceutical composition comprises in certain embodiments a single crystal form of ponatinib hydrochloride as the API. Alternatively, a unit dosage form of a pharmaceutical composition comprises more than one crystal form of ponatinib hydrochloride. In certain embodiments, more than about 50%, more than about 70%, more than about 80%, or more than about 90%, of a single crystalline form present in the composition is of one of the selected forms. In any of the foregoing embodiments, one or all of the crystal forms is substantially pure. For example, a pharmaceutical composition comprises in certain embodiments substantially pure Form A of ponatinib hydrochloride and at least one pharmaceutically acceptable carrier, vehicle or excipient. Alternatively, a pharmaceutical composition comprises Form A and Form J of ponatinib hydrochloride and at least one pharmaceutically acceptable carrier, vehicle or excipient. Other variations of this theme will be readily apparent to those of skill in the art given the benefit of this disclosure.
The at least one pharmaceutically acceptable carrier, diluent, vehicle or excipient can readily be selected by one of ordinary skill in the art and will be determined by the desired mode of administration. Illustrative examples of suitable modes of administration include oral, nasal, parenteral, topical, transdermal, and rectal. The pharmaceutical compositions disclosed herein may take any pharmaceutical form recognizable to the skilled artisan as being suitable. Suitable pharmaceutical forms include solid, semisolid, liquid, or lyophilized formulations, such as tablets, powders, capsules, suppositories, suspensions, liposomes, and aerosols.
Various solid forms of ponatinib, and various solid forms of ponatinib hydrochloride, may be administered singly or in any combination at a therapeutically effective amount to a subject in need of treatment. Similarly, any of the solid forms of ponatinib and ponatinib hydrochloride disclosed herein may be formulated singly or in any combination into a pharmaceutical composition that can be subsequently used to treat various disease states in humans or other animals. For example, pharmaceutical compositions comprising any single one or combination of polymorphs of ponatinib and/or ponatinib hydrochloride may be used for treating CML or Ph+ALL in a subject in need thereof, by the administration of a therapeutically effective amount of the pharmaceutical composition to the subject in need thereof.
Ponatinib free base and Ponatinib HCl are the products of the convergent four step synthesis depicted in Scheme 1. Step 1 involves the synthesis of the “methyl ester” intermediate AP25047 from starting materials AP24595, AP28141, and AP25570. Step 2 involves the synthesis of the “aniline” intermediate, AP24592, from starting material AP29089. Step 3 is the base catalyzed coupling of AP25047 and AP24592 to generate ponatinib free base, also designated as AP24534, which is isolated as the free base. Step 4 is the formation and crystallization of the mono-hydrochloride salt of ponatinib in ethanol.
A representative route of synthesis of ponatinib HCl is designated as Process C.
Summary and Synthetic Scheme
Step 1 of the ponatinib HCl process is the synthesis of the methyl ester intermediate AP25047 in a three reaction sequence (designated 1a, 1b, and 1c), carried out without intermediate isolation (“telescoped”), from starting materials AP24595, AP25570, and AP28141, as depicted in Scheme 1. The array of two aromatic ring systems connected by a single alkyne linker is constructed through two tandem, palladium/copper-catalyzed Sonogashira couplings and an in situ desilylation reaction under basic conditions. The crude AP25047 product is then subjected to a series of processing steps designed to remove residual inorganic catalysts and process by-products. These operations include the crystallization of AP25047 as the HCl salt from a non-polar solvent, toluene (Unit Operation 1.3), an aqueous work-up and silica gel plug filtration (Unit Operation 1.4), and crystallization from a polar solvent, 2-propanol (Unit Operation 1.5). The two crystallizations provide orthogonal purifications for rejection of related substance impurities with differing polarities. The crystallization and solvent wash of the HCl salt from toluene is controlled by an in-process analytical test for a specific process impurity. The final crystallization of the AP25047 intermediate from 2-propanol has been subjected to multi-variate DoE studies to define the design space for robust rejection of other impurities arising from the telescoped reactions. A series of eight in-process tests in Step 1 provide quantitative, analytical control for reaction completions, impurity rejection, and effective removal of residual solvents.
AP24595, palladium tetrakis triphenylphosphine (Pd(PPh3)4), copper (I) iodide (CuI), triethylamine, and tetrahydrofuran (THF) are charged to the reactor. The mixture is stirred and degassed with nitrogen and then pre-degassed AP28141 is charged. The resulting mixture is brought to 45-55° C. and held for not less than 3 hours. The reaction completion is determined by IPC-1 (HPLC). If the IPC-1 criterion is met, the mixture is concentrated to a target volume and cooled.
AP25570, additional palladium tetrakis triphenylphosphine (Pd(PPh3)4), copper (I) iodide (CuI), and tetrahydrofuran (THF) are charged to the reactor. The mixture is concentrated and the water content is determined by IPC-2 (KF). If the IPC-2 criterion is met, the mixture is warmed to 45-60° C. and 25% sodium methoxide solution in methanol is slowly added. The reaction mixture is stirred and held for 30-60 minutes at 45-55° C. The reaction progress is determined by IPC-3 (HPLC). The reaction mixture may be held at a lower temperature during the IPC analysis. If the IPC-3 criterion is met, the process is continued to Unit Operation 1.3.
While stirring, the cool reaction mixture is quenched by addition of hydrogen chloride gas. A precipitate forms, and residual hydrogen chloride is removed from the suspension by a nitrogen purge. Tetrahydrofuran (THF) is replaced with toluene by an azeotropic distillation under reduced pressure. The resulting warm slurry is filtered in an agitated filter dryer and the filter cake is triturated and washed with warm toluene. The content of process impurity AP29116 is determined by IPC-4 (H PLC). If the IPC-4 criterion is met, the wet filter cake is dried with agitation under a flow of nitrogen and reduced pressure at 35-45° C. (jacket temperature). The drying is monitored by IPC-5 (LOD, gravimetric). If the IPC-5 criterion is met, the crude AP25047 HCl is discharged and packaged in FEP bags in a plastic container. The isolated AP25047 HCl can be held for up to 7 days prior to forward processing.
The crude AP25047 HCl solid is charged to a reactor with dichloromethane (DCM) and washed with aqueous ammonia. The aqueous phase is back extracted with DCM for yield recovery purposes and the combined organic phase is washed a second time with aqueous ammonia. The organic layer is then washed with aqueous hydrochloric acid until the aqueous phase reaches a pH of 1-2, as indicated by IPC-6 (pH strips). If the IPC-6 criterion is met, the organic phase is treated with aqueous sodium bicarbonate until the aqueous wash reaches a pH of NLT 7, as indicated by IPC-7 (pH strips). The organic phase is briefly concentrated followed by the addition of fresh dichloromethane. The organic solution is passed through a silica gel pad, which is then rinsed with additional fresh dichloromethane for increased product recovery.
The dichloromethane solution is concentrated under reduced pressure, and the dichloromethane is replaced with 2-propanol by azeotropic distillation under reduced pressure to the targeted final volume range. The resulting suspension is then cooled and further aged with agitation.
The precipitated product is isolated in an agitated filter dryer under a flow of nitrogen, and the filter cake is rinsed with 2-propanol. The wet filter cake is dried with agitation under a flow of nitrogen and reduced pressure at 45-55° C. (jacket temperature). The drying is monitored by IPC-8 (LOD, gravimetric). If the IPC-8 criterion is met, the product is sampled and packaged into polyethylene bags and placed within a heat sealed mylar coated aluminum foil bag, within an HDPE shipping container (Expected yield range, 65-89%).
Step 2 of the ponatinib HCl process is the synthesis of the aniline intermediate, AP24592, by catalytic hydrogenation of the nitro-aromatic starting material AP29089, as depicted below. The reaction is carried out in ethyl acetate, a solvent in which the starting material and product are highly soluble. The catalyst for this reaction is palladium on carbon, and hydrogen is introduced as a gas directly into the reaction mixture. At the completion of the reaction, a solvent exchange from ethyl acetate to n-heptane via distillation prompts the spontaneous crystallization of AP24592, resulting in material with high purity. This crystallization has been shown to have a significant purification effect, as most of the process impurities remain solubilized in n-heptane.
The three in-process controls in Step 2 are an HPLC of the reaction mixture to confirm consumption of starting material, a GC measurement of ethyl acetate following the azeotropic solvent exchange to n-heptane, and a gravimetric determination of solvent loss on drying.
AP29089, 10% palladium on carbon, and ethyl acetate are charged to a reactor, and the suspension is stirred under hydrogen pressure.
The reactor is pressurized with hydrogen until a stable pressure range is achieved and the mixture is then stirred under hydrogen atmosphere for at least 4 additional hours. The reactor is depressurized and a sample taken to assess reaction completion (IPC-1). If the IPC-1 criterion is met, the process is continued to Unit Operation 2.3
The reaction mixture is passed through a filter cartridge to remove the catalyst, and the cartridge is washed with additional ethyl acetate. The combined filtrate and wash solution is concentrated under vacuum to remove a target volume of ethyl acetate. n-Heptane is charged, and the distillation is continued under vacuum to a target volume. The ethyl acetate content is determined by IPC-2 (GC). If the IPC-2 criterion is met, the process is continued to Unit Operation 2.4.
The solid product is dried under vacuum at a target temperature range. The end of drying is determined by IPC-3 (LOD, gravimetric). AP24592 is obtained as a white to yellow solid in a range of 80-97% (based on AP29089 input).
Step 3 is the synthesis of the free base of ponatinib by the base-catalyzed reaction of AP25047 and AP24592, presented in Scheme 4. The reaction is carried out in the presence of a strong base, potassium tert-butoxide, under essentially water-free conditions to minimize the undesired hydrolysis of the methyl ester of AP25047 to the corresponding unreactive carboxylic acid. The presence of this by-product results in not only loss of yield, but in complications in downstream processing during the reaction workup. Drying of the reaction mixture by a series of azeotropic distillations, controlled by an in-process test for water, ensures a robust reaction and nearly quantitative consumption of starting materials. The parameters of the reaction conditions and crystallization, in which process impurities are robustly rejected, are well understood on the basis of DoE studies.
AP25047, AP24592, and 2-methyl tetrahydrofuran (2-Me-THF) are charged to a reactor. The mixture is concentrated at reduced pressure to a target volume. Additional 2-methyl tetrahydrofuran is added and the distillation repeated. Following another charge of 2-methyl tetrahydrofuran and a distillation cycle, the water content of the mixture is determined in IPC-1(KF). If the IPC-1 criterion is met, the process is continued to Unit Operation 3.2.
The suspension is maintained with stirring at a target temperature of 13-23° C. range while potassium tert-butoxide (KOtBu) is charged. After a period of not less than 3 hours, the reaction progress is determined by HPLC (IPC-2). If the IPC criterion is met, the process is continued to Unit Operation 3.3.
The reaction mixture is diluted with 2-methyltetrahydrofuran (2-Me-THF), and quenched by the addition of aqueous sodium chloride solution. The organic layer is separated and the aqueous layer is extracted twice with 2-methyl tetrahydrofuran. The combined organic layers are sequentially washed with aqueous sodium chloride and water. The organic layer is then aged at 15-30° C.
After aging (see Unit Operation 3.3), the mixture is passed through a cartridge filter and concentrated under vacuum to a target volume. 1-Propanol is charged and allowed to stir at elevated temperature to furnish a solution, which is distilled under vacuum to a target volume and then cooled slowly to a temperature range of 20-30° C.
The product solution in 1-propanol is aged with stirring at a temperature of 20-30° C. until the presence of solids is visually observed. Acetonitrile is charged to the suspension with stirring and the resulting suspension is aged for an additional 60-120 minutes at 20-30° C. with agitation prior to isolation in the next Unit Operation.
The slurry generated in Unit Operation 3.5 is isolated under vacuum in a filter/dryer. The solids are washed twice with a mixture of 1-propanol and acetonitrile. The solids are then dried under vacuum and monitored by IPC-3 (LOD, gravimetric). If the IPC criterion is met, the product is discharged as an off-white to yellow solid and packaged in double polyethylene bags for storage at ambient temperatures.
Step 4 of the ponatinib HCl process is the formation of the mono-hydrochloride salt through combination of equimolar quantities of ponatinib free base with hydrochloric acid in ethanol and induction of crystallization through seeding. The parameters of this process have been examined in DoE studies for effects on the generation of the desired solid form and particle size distribution of this process. The synthetic scheme for Step 4 is presented in Scheme 5.
AP24534 free base and absolute ethanol (EtOH) are charged to a reactor and stirred at 60-75° C. to generate a solution. Dissolution is verified by visual observation.
The solution is passed through a filter, which is then washed with ethanol at 60-78° C.
The product solution is concentrated under vacuum to a target volume. With stirring, an initial portion (approximately 25%) of a solution of 1N hydrogen chloride in ethanol is then charged to the reactor. The solution is treated with qualified seed crystals of AP24534 HCl at a temperature of 60-70° C. to initiate crystallization. The process is continued to Unit Operation 4.4.
Once the presence of solids in the reactor is verified by visual observation, the remainder (approximately 75%) of the 1 N hydrogen chloride solution in ethanol is slowly added to the stirred mixture. The mixture is aged for at least 10 minutes and IPC-1 is performed to determine the pH of the solution. If the IPC criterion is met, the mixture is cooled to a temperature of 5-15° C. and aged with stirring.
The solid product is isolated by filtration and washed with ethanol at a temperature of 5-15° C. Excess ethanol is removed from the solid product by slow agitation and nitrogen flow at ambient temperature. The solid is then dried under vacuum at 60-70° C. The drying is monitored by IPC-2 (LOD, gravimetric). If the IPC-2 criterion is met, ponatinib HCl is discharged as an off-white to yellow solid and packaged in double polyethylene bags for storage in plastic drums at 20-30° C.
It is to be understood that the foregoing description is exemplary and explanatory in nature, and is intended to illustrate the presently disclosed general inventive concept and its preferred embodiments. Through routine experimentation, those of skill in the art given the benefit of the instant disclosure may recognize apparent modifications and variations without departing from the spirit and scope of the present disclosure. Thus, the present disclosure is not limited by the above description, but rather by the following claims and their equivalents.
This application is a continuation of U.S. application Ser. No. 16/146,143, filed Sep. 28, 2018, and issued as U.S. Pat. No. 10,066,197, which is a division of U.S. patent application Ser. No. 15/341,898, filed Nov. 2, 2016, and issued as U.S. Pat. No. 10,125,136, which is a division of U.S. patent application Ser. No. 14/651,577, filed Jun. 11, 2015, and issued as U.S. Pat. No. 9,493,470, which is a § 371 national stage entry of International Application No. PCT/US2013/074571, filed Dec. 12, 2013, which claims priority to U.S. Provisional Patent Application No. 61/736,543, filed Dec. 12, 2012; U.S. Provisional Patent Application No. 61/737,007, filed Dec. 13, 2012; and U.S. Provisional Patent Application No. 61/788,208, filed Mar. 15, 2013, which are incorporated herein by reference in their entireties.
| Number | Date | Country | |
|---|---|---|---|
| 61736543 | Dec 2012 | US | |
| 61737007 | Dec 2012 | US | |
| 61788208 | Mar 2013 | US |
| Number | Date | Country | |
|---|---|---|---|
| Parent | 16881790 | May 2020 | US |
| Child | 17318876 | US | |
| Parent | 15341898 | Nov 2016 | US |
| Child | 16146143 | US | |
| Parent | 14651577 | Jun 2015 | US |
| Child | 15341898 | US |
| Number | Date | Country | |
|---|---|---|---|
| Parent | 16146143 | Sep 2018 | US |
| Child | 16881790 | US |
