FIELD OF THE INVENTION

Aspects of the present invention relate to pharmaceutical compositions comprising proteasome inhibitors. Further aspects of the invention relate to process for preparing pharmaceutical compositions comprising proteasome inhibitors.

BACK GROUND OF THE INVENTION

Proteasome inhibitors are drugs that block the action of proteasomes, cellular complexes that break down proteins, like the p53 protein. Proteasome inhibitors are being studied in the treatment of cancer more prominently since last decade, especially for multiple myeloma.

In normal course of cellular functioning, it requires processing of proteins regulating Cell cycle, Growth, and Apoptosis. The ubiquitin-proteasome pathway (UBP) modulates intracellular protein degradation. Specifically, the 26S proteasome is a multi-enzyme protease that degrades misfolded or redundant proteins; conversely, blockade of the proteasomal degradation pathways results in accumulation of unwanted proteins and cell death.

Cancer cells are more highly proliferative than normal cells and their rate of protein translation and degradation is also faster. This typical behavior led to the development of various proteasome inhibitors as useful therapeutics in cancer. The FDA approved the first proteasome inhibitor bortezomib (Velcade) for the treatment of newly diagnosed and relapsed/refractory multiple myeloma. Other improved and II generation proteasome inhibitor approved recently includes Carfilzomib. Further on-going studies are examining other novel proteasome inhibitors, in addition to bortezomib, for the treatment of multiple myeloma and other cancers. Well known Proteasome inhibitors known today are Bortezomib (A), Carfilzomib(B), Marizomib(C)

Bortezomib -chemically known as ((N-(2-pyrazine) carbonyl-L-phenylalanine-L-leucine boronic acid) is a 26S proteasome inhibitor that is approved for use in treatment of relapsed multiple myeloma and mantle cell lymphoma. It is believed that the boron atom in bortezomib binds to the catalytic site of the proteasome, ultimately leading to proteasome inhibition and reduced degradation of pro-apoptotic factors, which in turn triggers apoptosis in treated cells.

Stability of aminoalkylboronic acids (including bortezomib) has remained a concern as they often undergo a spontaneous 1,3-rearrangement to give the homologous amines, owing to the instability of free a-amino groups. These compounds yield boric acids and alcohols by degradation and undergo oxidative reactions that easily destroy the C-B bond which is longer and weaker than the corresponding C-C bond (see e.g., Adele Bolognese, Anna Esposito, MicheleManfra, Lucio Catalano, Fara Petruzziello, Maria CarmenMartorelli, Raffaella Pagliuca, VittoriaMazzarelli, Maria Ottiero, Melania Scalfaro, and Bruno Rotoli. Advances in Hematology, 2009 (2009) 1-5). Such instability is borne out in stress testing and accelerated stability studies of bortezomib that has established that bortezomib in aqueous solution for injection is intrinsically unstable. For example, in an ethanol:normal saline solution (2:98, pH 2.8), Bortezomib (0.5 mg/mL) degraded 20% at 25°C in 1 month, and in propylene glycol: ethanol: water (50:10:40), the stability of the compound improved, but still degraded 20% in 8 months when stored at 25.degree. C. Among other factors, it was speculated that the degradation of Bortezomib observed in PEG300:EtOH:H2O (40:10:50) solvent might be due to the presence of peroxides, as PEG300 is known to undergo auto-oxidation with concomitant peroxide generation. (Journal of Pharmaceutical Sciences, 89,2000 758-765).

In other studies, bortezomib was reported to be susceptible to oxidative degradation under a number of experimental conditions, and that the oxidation of alkyl boranes (which yields the ester of boric acid) can also be due to reaction with alkyl peracids, alkyl peroxides, or oxygen radical species. (Brown H C. 1972. Boranes in organic chemistry. Ithaca, N.Y.: Cornell University Press.). The initial oxidation can be attributed to peroxides or molecular oxygen and its radicals and as light, metal ions, and alkaline conditions normally facilitate oxidation. These conditions are therefore not considered favorable to the stability of bortezomib or any other alkyl boronic acid derivative. (Hussain M A, Knabb R, Aungust B J, Kettner C.1991. Anticoagulant activity of a peptide boronic acid thrombin inhibitor by various routes of administration in rats. Peptides 12:1153-1154).

Formation of boronic esters from diol and polyols was reported by Kuivila et al. reporting the preparation of several esters of phenylboronic acid by reaction with sugars like mannitol and sorbitol, and 1,2-diols like catechol and pinacal. (J. Org. Chem. 1954, 8, 780-783), and reversible formation of boronic ester by the interaction of boronic acids and polyols in water was first noted by Lorand and Edwards. (J. Org. Chem. 1959, 24, 769-774).

Adams et al in US5780454 discloses Bortezomib, its pharmaceutically acceptable salts, pharmaceutical composition and use in inhibiting the proteosome function in a mammal.

Further, it discloses a process for the preparation of Bortezomib and its analogues.
Gupta et al in US6713446 discloses lyophilized formulation of Bortezomib esters. This patent mentions that Bortezomib prepared by the process as described in US5780454 is white amorphous powder.

Attempts to form the ester of boronic acid with alpha-hydroxy and beta-carboxylic acids like citric acid and with buffers were disclosed in WO 2009/154737.

Namdeo et al in WO2010089768 discloses parenteral pharmaceutical composition comprising therapeutically effective amounts of N-(2-pyrazine) carbonyl-L-phenylalanine-L-leucine boronic acid or its salts or its derivatives and tromethamine wherein the composition is stable.

Kocherlakota et al in WO2010039762 disclose pharmaceutical compositions comprising bortezomib for oral or parenteral administration. Specific aspects relate to stable, sugar free pharmaceutical compositions of bortezomib, including its pharmaceutically acceptable salts or solvates, in the form of ready-to-use solutions, lyophilized forms, or physical admixtures, and the preparation thereof.

Bricout et al in WO2010114982 disclose a lyophilized cake comprising bortezomib or a pharmaceutically acceptable salt or ester thereof, a cyclodextrin and atleast one member selected from the group of bulking agents and surfactants.

Soppimath et al in US8263578 disclose a storage-stable liquid pharmaceutical composition that includes bortezomib in a therapeutically effective amount, the composition comprising: a

single-phase liquid formulation comprising a substantially non-aqueous solvent system suitable for injection, an aqueous acetate buffer, and bortezomib, wherein the bortezomib is present in the formulation at a therapeutically effective concentration; wherein the solvent system comprises as a predominant component propylene glycol, and wherein the buffer has a pH of 3; and wherein the solvent system, the buffer, and the pH are selected such as to be effective to suppress formation of at least one of an amide degradation product, a first carbinolamide degradation product, and a second carbinolamide degradation product when the liquid formulation is stored under storage conditions.

Usayapant et al in WO2012047845 disclose a bortezomib composition includes bortezomib and boric acid in a mass ratio of boric acid to bortezomib is from 1:1 to 10:1.
Anderson et al in WO2012148799 disclose a non-aqueous, homogeneous solution comprising a solubilized lipophilic pharmaceutical agent and an amphiphilic liquid polymeric solvent, the formulation being essentially free of non-polymeric organic solvents, water and non-solubilized particles, wherein the solubilized lipophilic pharmaceutical agent has a concentration of at least about 0.5 mg/mL, and further wherein the solution remains stable and essentially free of non-solubilized particles for at least 40 days when stored at room temperature.

Further known disclosures for Bortezomib include- WO2008075376, WO2011099018, WO2011107912 and WO2012131707.

Hence, despite disclosure of many formulations for bortezomib known in the art, almost all of them suffer from the concern of limited stability when bortezomib or similar proteasome inhibitor is in solution, particularly over extended periods. Thus, there still appears a need to provide improved formulation approach for the proteasome inhibitors of interest to possess improved stability.

SUMMARY OF THE INVENTION

Aspects of the present invention relate to a pharmaceutical composition comprising Bortezomib (I) as monohydrate Form-SB devoid of any pharmaceutically acceptable excipient, wherein said composition is having moisture content in the range of 3.5%-6.5%w/w.
Aspects of the present invention relate to a lyophilized composition comprising Bortezomib (I) as monohydrate Form-SB.

Aspects of the present invention relate to a pharmaceutical composition comprising for parenteral administration about 0.1 mg/ml to about 10 mg/ml Bortezomib, calculated as Bortezomib monohydrate (I).

Aspects of the present invention relate to a lyophilized composition; wherein in amount of solvent vehicle comprising organic solvent and water is in the ratio of 20:80 (v/v) to 30:70 (v/v).

Aspects of the present invention relate to a pharmaceutical composition comprising Bortezomib (I) as monohydrate Form-SB, wherein the composition before lyophilization has a pH value of 5.0 to about 7.

Aspects of the present invention relate to a lyophilized powder comprising Bortezomib (I) as monohydrate Form-SB, being suitable for reconstitution to form a liquid composition, with aqueous solution for parenteral administration, wherein the lyophilized powder is having moisture content in the range of 3.5%-6.5%w/w.

Aspects of the present invention relate to a method of using a pharmaceutical composition for the manufacture of a medicament for the treatment of cancer in a mammal, wherein the pharmaceutical composition comprises Bortezomib monohydrate (I) form-SB, devoid of any pharmaceutically acceptable excipient, to form a lyophilized cake, wherein the composition is having moisture content in the range of 3.5%-6.5%w/w, the method comprising forming the medicament from the pharmaceutical composition.

Aspects of the present invention relate to a process for preparing a
pharmaceutical composition containing a Bortezomib (I) as monohydrate Form-SB, which process comprises the steps of:

i) Preparing water of injection solution containing dissolved oxygen content of less than 5ppm by nitrogen purging.

ii) dissolving Bortezomib (I) monohydrate Form-SB in tertiary butanol to form a uniform white suspension;

iii) Mix the suspension of step (ii) with (i) under stirring.

iv) filtering the solution obtained in step (iii) to obtain a filtered solution;

v) lyophilizing the filtered solution of step (iv), wherein the lyophilized composition is having moisture content in the range of 3.5%-6.5%w/w.

Aspects of the present invention relate to a method of treating a patient for cancer comprising: reconstituting a pharmaceutical composition by combining a lyophilizedpowder comprising Bortezomib (I) as monohydrate Form-SB, with an aqueous solution to form the reconstituted pharmaceutical composition that is free of visual particles; and injecting the reconstituted pharmaceutical composition intravenously or subcutaneously, into a patient.

Aspects of the present invention relate to a reconstituted pharmaceutical composition comprising Bortezomib (I) as monohydrate Form-SB, wherein the aqueous solution comprises saline or physiological saline.

BRIEF DESCRIPTION OF THE DRAWING

Fig. l is Illustration of X-ray powder diffraction (XRPD) pattern of Bortezomib (I) as monohydrate Form-SB.

Fig.2 is Illustration of DSC thermogram of Bortezomib (I) as monohydrate Form-SB.

Fig.3 is Illustration of IR spectra of Bortezomib (I) as monohydrate Form-SB.

DETAILED DESCRIPTION OF THE INVENTION

In embodiment of the present invention, provides a pharmaceutical composition comprising Bortezomib (I) as monohydrate Form-SB devoid of any pharmaceutically acceptable excipient, wherein said composition is having moisture content in the range of 3.5%-6.5%w/w.

In a particular embodiment of the present invention, it provides a pharmaceutical composition comprising Bortezomib (I) as monohydrate Form-SB
V7J devoid of any pharmaceutically acceptable excipient, wherein said composition is having moisture content in the range of 4.0%-5.0%w/w.

In embodiment of the present invention, it provides a pharmaceutical composition prepared using Bortezomib (I) as monohydrate Form-SB having moisture content in the range of 5% -8.0% w/w. Said Bortezomib monohydrate Form-SB is further characterized by X-ray powder diffraction pattern comprising the characteristic 29°peaks of 5.6, 7.5, 9.8, 10.2,11.3, 15.1, 18.0, 20.5, 21.5 and 23.6 ± 0.20 20° (according to Fig-I), DSC isotherm comprising the endothermic peaks ranging between 45 to 60 °C (Peak -1) and 175 to 185°C (Peak -2) (according to Fig-II) and IR absorption characteristic peaks at approximately at 3387 cm"1, 3304 cm"1, 2953 cm"1, 2927 cm"1, 2868 cm"1, 1627 cm"1, 1455 cm"1, 1400 cm1, 1201cm"1, 1150cm"1, 1020 cm"1, 747 cm"1 and 702 cm"1 (according to Fig-III).

In the pharmaceutical composition of the present invention, Bortezomib other forms may also be utilized to prepare the said compositions which may be devoid of any pharmaceutically acceptable excipient, wherein said composition is having moisture content in the range of 3.5%-6.5%w/w.

The compositions according to the present invention for proteasome inhibitors including Bortezomib, Carfilzomib, Marizomib or the like may be derived from the same approach which may be devoid of any pharmaceutically acceptable excipient/s however, excepting the use of any sugar based esterified compounds in the said composition.

In embodiment of the present invention, it provides a lyophilized composition comprising Bortezomib (I) as monohydrate Form-SB.

In embodiment of the present invention, it provides a pharmaceutical composition comprising for parenteral administration about 0.1 mg/ml to about 10 mg/ml Bortezomib, calculated as Bortezomib monohydrate (I).

amount of solvent vehicle comprising organic solvent and water is in the ratio of 20:80 (v/v) to 30:70 (v/v).

In preferred embodiment of the present invention, it provides a lyophilized composition; wherein in amount of solvent vehicle comprising organic solvent and water is in the ratio of 30:70 (v/v).

In embodiment of the present invention, it provides a pharmaceutical composition comprising Bortezomib (I) as monohydrate Form-SB, wherein the composition before lyophilization has a pH value of 5.0 to about 7.

In embodiment of the present invention, it provides a lyophilized powder comprising Bortezomib (I) as monohydrate Form-SB, being suitable for reconstitution to form a liquid composition, with aqueous solution for parenteral administration, wherein the lyophilizedpowder is having moisture content in the range of 3.5%-6.5 %w/w.

In embodiment of the present invention, it provides a method of using a pharmaceutical composition for the manufacture of a medicament for the treatment of cancer in a mammal, wherein the pharmaceutical composition comprises Bortezomib monohydrate (I) form-SB, devoid of any pharmaceutically acceptable excipient, to form a lyophilized cake, wherein the composition is having moisture content in the range of 3.5% - 6.5 %w/w, the method comprising forming the medicament from the pharmaceutical composition.

In embodiment of the present invention, provides a process for preparing pharmaceutical composition containing a Bortezomib (I) as monohydrate Form-SB, which process comprises the steps of:

i) Preparing water of injection solution containing dissolved oxygen content of less than 5ppm by nitrogen purging.

ii) dissolving Bortezomib (I) monohydrate Form-SB in tertiary butanol to form a uniform white suspension;

iii) Mix the suspension of step (ii) with (i) under stirring.

iv) filtering the solution obtained in step (iii) to obtain a filtered solution;

v) lyophilizing the filtered solution of step (iv), wherein the lyophilized composition is having moisture content of 3.5%-6.5 % w/w; wherein the lyophilization cycle involves following steps:

a. Precoolingofshelfat-5°to5°C

b. Freezing at -40 ± 5° C for 4 to 6 hours.

c. Primary drying at -45° C for 2 to 3 hours at 0.06-0.5 mbar.

d. Primary drying at -35± 3° C for 16 to 20 hours at 0.2 mbar.

e. Primary drying at -15± 5°C for 4 to 6 hours at 0.2 mbar.

f. Primary drying at 0° C for 4 to 6 hours at 0.2 mbar.

g. Primary drying at 25° C for 10 to 14 hours at 0.06 mbar.

h. Secondary drying at 40° C for 6 to 10 hours at 0.06 mbar.

vi) After the completion of lyophilization, completely stopper the vials under Nitrogen, unload and seal with flip off aluminium seals.

In embodiment of the present invention, it provides a method of treating a patient for cancer comprising: reconstituting a pharmaceutical composition by combining a lyophilized powder comprising Bortezomib (I) as monohydrate Form-SB, with an aqueous solution to form the reconstituted pharmaceutical composition that is free of visual particles; and injecting the reconstituted pharmaceutical composition intravenously or subcutaneously, into a patient.

In embodiment of the present invention, it provides a reconstituted pharmaceutical composition comprising Bortezomib (I) as monohydrate Form-SB, wherein the aqueous solution comprises saline or physiological saline.

In embodiment of the present invention, it provides a lyophilized composition supplied in a vial: l0mL / 20mm Flint Tubular Flat bottom Type-I USP/Ph.Eur.

In embodiment of the present invention, it provides a lyophilized composition supplied in a l0mL vial: with a Stopper: 20mm Dark Grey Bromo butyl rubber stoppers.

In embodiment of the present invention, it provides a lyophilized composition supplied in a l0mL vial: with a Seals: 20 mm Orange flip off aluminium seal.

By "pharmaceutical composition" or "lyophilized composition" is meant any composition having sufficient stability to have utility as a pharmaceutical agent. Preferably, the formulation has sufficient stability to allow storage at a convenient temperature, preferably between 0°C and 40°C, for a reasonable period of time, preferably longer than one month, more preferably longer than three months, even more preferably longer than six months, and most preferably longer than one year. Also, the term "lyophilized composition" as used herein means that the pharmaceutical composition when in the form of a lyophilized cake or powder that is the composition is not reconstituted, remains unaltered in terms of physical and chemical parameters for a prolonged period of time when packed in container which are either protected or unprotected against light, under various storage conditions. For instance, when the containers such as vials are not opened and are stored at controlled room temperature 25°C (77°F) with variation to a range of about 15 to 30°C (59 °F to 86°F) the pharmaceutical composition of the present invention remains stable for 6 months. The pharmaceutical composition when reconstituted with a suitable reconstitution medium such as water for injection or physiological saline, the reconstituted solution is said to be stable when there is no significant chemical degradation for at least 8 hours and there are no signs of precipitation or appearance of particles in the clear solution on storage at room temperature for the said time.

The term "organic solvent" means an organic material, usually a liquid, capable of dissolving other substances. In different aspects of this embodiment, the organic solvent selected from tertiary-butyl alcohol, acetonitrile etc.

The term "pharmaceutically acceptable" refers to an ingredient that is useful in preparing a pharmaceutical composition that is generally safe, non-toxic, and neither biologically nor otherwise undesirable, and includes those acceptable for veterinary use as well as human pharmaceutical use.

Example 1

Bortezomib Lyophilized composition for injection 3.5mg / Vial.

Brief method of preparation:

i) Preparing water of injection solution containing dissolved oxygen content of less than 2 ppm by nitrogen purging.

ii) dissolving Bortezomib (I) monohydrate Form-SB in tertiary butanol to form a uniform white suspension;

iii) Mix the suspension of step (ii) with (i) under stirring.

iv) filtering the solution obtained in step (iii) to obtain a filtered solution;

v) lyophilizing the filtered solution of step (iv), wherein the lyophilized composition is having moisture content of 3.5%-6.5 %w/w; wherein the lyophilization cycle involves following steps:

a. Precoolingofshelfat-5°C.

b. Freezing at -45°C for 4 to 6 hours.

c. Primary drying at -45° C for 2 to 3 hours at 0.1 mbar.

d. Primary drying at -35° C for 16 to 20 hours at 0.2 mbar.

e. Primary drying at -15°C for 4 to 6 hours at 0.2 mbar.

f. Primary drying at 0°C for 4 to 6 hours at 0.2 mbar.

g. Primary drying at 25° C for 10 to 14 hours at 0.06 mbar.

h. Secondary drying at 40°C for 6 to 10 hours at 0.06 mbar.

vi) After the completion of lyophilization, completely stopper the vials under Nitrogen, unload and seal with flip off aluminium seals.

Example 2

Bortezomib Lyophilized composition for injection 3.5mg/Vial.

Brief method of preparation:

i) Preparing water of injection solution containing dissolved oxygen content of less than 2ppm by nitrogen purging.

ii) dissolving Bortezomib (I) monohydrate Form-SB in tertiary butanol to form a uniform white suspension;

iii) Mix the suspension of step (ii) with (i) under stirring.

iv) filtering the solution obtained in step (iii) to obtain a filtered solution;

v) lyophilizing the filtered solution of step (iv), wherein the lyophilized composition is having moisture content of 3.5%-6.5 %w/w; wherein the lyophilization cycle involves following steps:

Precoolingofshelfat2°C.

Freezing at -45 °C for 4 to 6 hours.

Primary drying at -47° C for 2 to 3 hours at 0.3 mbar.

Primary drying at -36° C for 16 to 20 hours at 0.2 mbar.

Primary drying at -10°C for 4 to 6 hours at 0.2 mbar.

Primary drying at 0°C for 4 to 6 hours at 0.2 mbar.

Primary drying at 25° C for 10 to 12 hours at 0.06 mbar.

Secondary drying at 42°C for 6 to 9 hours at 0.06 mbar.

vi) After the completion of lyophilization, completely stopper the vials under Nitrogen, unload and seal with flip off aluminium seals.

Claims:
1. A pharmaceutical composition comprising Bortezomib (I) as monohydrate Form-SB devoid of any pharmaceutically acceptable excipient, wherein said composition is having moisture content in the range of 3.5%-6.5 %w/w.

2. The pharmaceutical composition of claim 1, wherein the pharmaceutical composition is a lyophilized composition.

3. The pharmaceutical composition of claim 1, comprising for parenteral administration about 0.1 mg/ml to about 10 mg/ml Bortezomib, calculated as Bortezomib monohydrate (I).

4. The pharmaceutical composition of claim 2, wherein the composition before lyophilization has a pH value of 5.0 to about 7.

5. A lyophilized powder formed from the pharmaceutical composition according to
The preceding claims being suitable for reconstitution to form a liquid composition, with aqueous solution for parenteral administration, wherein the lyophilized powder is having moisture content in the range of 3.5%-6.5 %w/w.

6. A method of using a pharmaceutical composition for the manufacture of a medicament for the treatment of cancer in a mammal, wherein the pharmaceutical composition comprises Bortezomib monohydrate (I) form-SB, devoid of any pharmaceutically acceptable excipient, to form a lyophilized cake, wherein the composition is having moisture content in the range of 3.5%-6.5 %w/w, the method comprising forming the medicament from the pharmaceutical composition.

7. A process for preparing a pharmaceutical composition containing a Bortezomib (I) as monohydrate Form-SB, which process comprises the steps of:

i) Preparing water of injection solution containing dissolved oxygen content of less than 5ppm by nitrogen purging.

ii) dissolving Bortezomib (I) monohydrate Form-SB in tertiary butanol to form a uniform white suspension;

iii) Mix the suspension of step (ii) with (i) under stirring.

iv) filtering the solution obtained in step (iii) to obtain a filtered solution;

v) lyophilizing the filtered solution of step (iv), wherein the lyophilized composition is having moisture content in the range of 3.5%-6.5 %w/w.

8. A method of treating a patient for cancer comprising: reconstituting a pharmaceutical composition by combining a lyophilized powder according to claim7 with an aqueous solution to form the reconstituted pharmaceutical composition that is free of visual particles; and injecting the reconstituted pharmaceutical composition intravenously or subcutaneously, into a patient.

9. The reconstituted pharmaceutical composition of claim 8, wherein the aqueous solution comprises saline or physiological saline.