WO2005074889A1

WO2005074889A1 - Novel compositions of taxol derivatives and the process for the manufacture thereof

Info

Publication number: WO2005074889A1
Application number: PCT/IN2004/000037
Authority: WO
Inventors: Dinesh Shantilal Patel; Sachin Dinesh Patel; Shashikant Prabhudas Kurani
Original assignee: Dinesh Shantilal Patel; Sachin Dinesh Patel; Shashikant Prabhudas Kurani
Priority date: 2004-02-03
Filing date: 2004-02-03
Publication date: 2005-08-18

Abstract

Novel and stable formulation of Paclitaxel in a system comprising Paclitaxel or its derivatives and 2,5 di-0-methyl 1:3:4:6 dianhydroglucitol or its analogs thereof Paclitaxel or derivatives thereof may be suitably dissolved in 2,5 di-0-methyl 1:3:4:6 dianhydroglucitol or its analogs thereof and prepared in the concentration range of 0.2 mg/ml to 50 mg/ml yielding clear stable solution which can be administered as a slow bolus injection or through infusion pump or by parenteral administration admixing simultaneously online with saline or glucose.

Description

NOVEL COMPOSITIONS OF TAXOL DERIVATIVES AND THE PROCESS FOR THE MANUFACTURE THEREOF

Field of invention:

This present invention relates to novel composition of taxol derivatives and the process to manufacture thereof.

Background of the Invention:

Various plant alkaloids have been tested for and are seen to have activity against tumor cells.

Vinca alkaloids, for example, isolated from periwinkle plant Catharanthus roseus are known for the source of vincristine and vinblastine. Their activity against the tumor cells is because of their specific interaction with tubulin by preventing assembly of tubulin into microtubules and arresting the cell division. These alkaloids are useful for Hodgkins disease and metastatic testicular tumors.

The alkaloid camptothecin, isolated from the tree Camptotheca acmninata and the derivatives of the same have been used for the various type of cancers.

Podophyllin, derived from Podophyllum ?e/tαt«m and the derivative of the same has also been used as an anticancer agent.

Members of the taxene family like Paclitaxel and Docetaxel are also recognized as potent anticancer agents. Paclitaxel is isolated from pacific yew (Taxus brevifolia) whereas Docetaxel is synthesized from noncytotoxic precursor, isolated from more readily accessible European yew (Taxus baccata).

Paclitaxel also termed as taxol, functions by stabilizing microtubules and preventing their disassembly. With its unique mechanism of action, tubulin stabilization, it prevents cell division by promoting the assembly of and inhibiting the disassembly of microtubules - skeletal structures that assemble and divide throughout the life of a cell.

Chemically taxol is classified as a taxane diterpenoid or taxoid. Diterpenoids are natural products with a C-20 carbon skeleton derived biogenetically from geranyl geraniol pyrophosphate. taxol is the most famous and most studied member of the large family of taxene diterpenoids. There are over 200 cousins of taxol in this family, and almost all of them have the basic pentadecene ring system.

The basic skeleton of taxol is:

All known taxoids to date with one exception have been isolated from plants of the Taxaceae family and most from various Taxus species, taxol differs from most other taxoids in two respects. First, its taxane skeleton is esterified at the C-13 position with a complex N-benzoylphenylisoserine ester group, which is known as the taxol side-chain. The C13 side chain is highly flexible and rapidly achieves different alternative conformations depending upon the solvents used during the preparation. Secondly it also has an oxetane ring attached to C 4 & 5 position. These are the essential features for the biological activity.

The structures of Paclitaxel and Docetaxel can be elucidated as below: Structure of Paclitaxel Structure of Docetaxel

Paclitaxel Docetaxel

Commercial production of Paclitaxel is considered as tedious, time consuming and expensive since it is found that the source for this agent Taxus brevifolia yields very small amount of Paclitaxel and huge amount of plant material is required for the extraction of few mg of the drug material.

An alternative source available for the extraction of Paclitaxel, as known from the literature survey is by harvesting the needles of the plant Taxus canadansis.

It was thus observed that due to the limited supply of Paclitaxel its formulation was always an issue of concern. Additionally the poor aqueous solubility of Paclitaxel leads to several difficulties in the formulations.

Prior art shows that several derivatives, semi synthetic in nature were prepared with modification in C13 side chain leading to better solubility. This was expected to give better potency. Due to its limited solubility in water, Paclitaxel is usually prepared and administered in a vehicle containing Cremophor EL (Source: CremophorEL: Badische Anilin und Soda Fabrik AG [BASF]. Ludwigshafen. Federal Republic of Germany) a polyethoxylated caster oil which acts as a solubilizer and ethanol.

In 1983 first clinical trial for taxol was initiated and got vitiated because of the formulation contained a very high level of lipid based adjuvants i.e. hydrogenated castor oil which lead to severe allergic reactions in many human volunteers and systemic side effects like neutropenia, peripheral neuropathy and hypersensitivity reactions.

Subsequent trial in 1985 with the improved formulation showed some benefit in the refractory ovarian cancer and hence, first approval by FDA was given in 1993 for the treatment of metastatic breast cancer. However this formulation still had Cremophor as excipient, which thus was not devoid of side effects.

It was thus evident that the formulation of taxol for antineoplastic testing is difficult due to its extremely low aqueous solubility.

The present approved and marketed formulation contains Cremophor and ethyl alcohol as the solvent for solubilizing the same.

It was observed that administration of taxol formulation during clinical trials has led to hypersensitivity reactions due to the presence of Cremophor EL. To overcome such anaphylactoid reactions, patients are treated by administering corticosteroids and H2 receptor antagonist as premedication.

These injections have to be further diluted before administration and it was noted that the injections containing Cremophor lead to precipitation of adjuvant and Paclitaxel after dilution with physiological saline / 5% glucose thereby requiring additional assembly of filtration (through 0.22μ filter) to assure safety during administration. The use of alcohol in the formulation and its use during the administration also causes the acute intoxication (348 mg/m2 body surface) which supplies 50 ml of alcohol or equivalent of about 3 drinks to the body (half a bottle of wine) (Ref: Willson DB, et al. Paclitaxel formulation as a cause of ethanol intoxication. Ann Pharmacother 1997; 31: 873-5, Martindale, 33^rd Edition)

Further in few patients the use of steroids is also known to cause optic neuritis and glaucoma during the premedication in the use of above marketed formulation of steroids. (Ref .Fabre-Guillevin E, et al. Taxen-induced glaucoma. Lancet 1999; 354:1181-2, Martindale 33^rd Edition).

There are various prior art patents disclosing means of overcoming hypersensitivity reactions and toxicity caused to humans.

Patent AU651307 describes the method of administration of taxol and cites how critical is the problem of hypersensitivity reaction (kris et al) and dosage ranging from 15 - 230 mg/m when administered as infusion for 3 hrs, every 21 days in escalating steps (Cancer Treat. Rep. Vol. 70, No.5 May 1986.

Weiss et al describes hypersensitivity reactions from taxol, "Journal of Clinical Oncology Vol. 8, No. 7, July 1990 pp. 1263 - 1268.

This literature expresses how difficult it is to presume hypersensitivity reaction during the administration because of variation in doses of taxol at different time schedules and unknown physiological influence of the individuals. The regimen also required long duration of infusion and premedication of the drugs reducing the hypersensitivity reactions occurring due to the presence of Cremophor EL with continuous monitoring of the patient.

AU651307 also claims method of administration of effective amount of taxol in the concentration of 135 mg/m to 175mg/m along with sufficient premedication to prevent anaphylactic like reactions. This formulation is also packed in separate chambers for the sequential or simultaneous therapeutic use for the treatment of ovarian cancer over a period of about 24 hrs or less, which is inconvenient for the doctors.

WO9412198 describes the injectable composition of taxol showing the improved stability using the adjustment of pH with acids at pH less than 8.1. This document however, still describes the use of Cremophor EL™ with citric acid and ethanol.

WO9904787 describes Vitamin E as a solubilizer for Paclitaxel, however, it also describes methanol as a solvent during solubilization stage. This type of solution has its own potential limitation because of the toxicity related to use of methanol. Even the traces of methanol can cause side effect of retinopathy and loss of renal function if the level of methanol in the formulation is not monitored. Further this document also hints at regularization of the particle size of Paclitaxel in the formulation. Additionally use of costly material like Vitamin E for solubilization limits the commercial feasibility of this method.

WO94/12198 describes the stability of taxol using citric acid for the adjustment of pH in the formulation. This however still hints the use of Cremophor EL /ethanol.

This document aims to stabilize Paclitaxel solution by adjusting the pH of the solution. The marketed formulation has a pH of 9.0 and the pH of the solution in this document is said to be adjusted in the range of 5.0 to 7.5 and preferably 6.1 for improved stability. Furthermore, it claims preferred use of anhydrous citric acid for the adjustment of the pH.

This document however teaches only the chemical stability of the formulation but does not hint for resolving the issues of Hypersensitivity related to use of Cremophor EL in the formulation. Thus the issue related to anaphylactoid type reaction remains an impending and unresolved issue.

EP0473326 Al equivalent to US573731 hints at use of various aqueous soluble taxol derivatives. However, one may appreciate that this requires synthetic steps to produce such a derivative from the existing scarce material and requiring many investigations including physical, chemical stability & clinical use. Presently no such derivatives are in the market for the treatment of cancer.

WO9318751 describes liposomal-based formulation of taxol for the treatment of Cancer and is used in conjunction with treatment of patient with hyperthermia. It has been claimed to be a stable formulation. However, liposomal-based formulations are seen to have inherent problems related to stability and cause an increase in bioburden. An additional disadvantage of this preparation is that it describes the use of chloroform and hexane during the preparation of liposomes which if remains as a residue may cause toxic effects including inducement of cancer. Thereby it would be difficult to identify if the cause of toxicity is related to Paclitaxel or due to the solvent residue used during the intravenous administration.

EP1332755 Al describes liposomal-based formulations for the treatment of Cancer and preparation thereof. This invention again describes the use of organic solvents, amino acids, sugar and phosphatide derived from egg yolk or soyabean. The use of such substances is known to increase the bio burden to the formulations and increase toxicity.

Recent clipping from New York Times of December 08,2003 hints for the preparation of Paclitaxel formulation using albumin which is a substance derived from animal origin. However it is known that albumin causes antigenic reactions when administered parenterally. Though this evidently avoids use of Cremophor, the amount of albumin which is used for such attachment of Paclitaxel is more than 10% and still requires investigation about antigenicity unless proved otherwise

Thus a review of prior art shows that the formulations of Paclitaxel disclosed and the present marketed formulation are shown to cause anaphylactoid reactions, dyspnea, hypertension and flushing and cardiac toxicity due to the presence of castor oil derivative i.e. Cremophor and alcohol. These further deteriorate the already morbid state of the patient. These are thus the limiting factors for the present treatment of cancer using taxol derivatives, which require hospitalization of the patient.

Furthermore the stability of the solution is also a cause of the concern and hence the management of the dosage is difficult to handle. Presently the marketed formulation of taxol is available as stock solution of 6 mg/ml in 5 ml pack or multiple thereof and is administered through saline by directly pouring in saline or glucose by administrating intravenously. This procedure of mixing degrades the taxol and also precipitates the material formulated in the preparation.

From all above prior arts and the existing formulation available in the market there still seems to be a need of a Paclitaxel formulation which is devoid of anaphylactoid reactions which is also a stable solution, economic to prepare and easy to administer avoiding the use of extraneous biological materials like ethanol, albumin and phospolipids.

Thus there is a long felt consistent need to formulate Paclitaxel formulation that b the above limitations and minimizes the impact of toxicity.

The present inventors have addressed this need by formulating an easy to administer clear solution of Paclitaxel with a better bioavailability and stability using an inexpensive and non-toxic solvent.

Objects of the invention:

It is thus an object of the invention to provide a composition of Paclitaxel that overcomes the solubility and stability problems existing with the prior art.

It is a further object of the invention to provide a stable Paclitaxel composition.

Yet another object of the invention is to provide an easy to administer clear composition of Paclitaxel with a better bioavailability and stability using an inexpensive and non-toxic solvent. A further object of the invention is to provide a non-toxic composition of Paclitaxel that eliminates the anaphylactoid or hypersensitivity reactions or cardio-toxic indications during its administration associated due to the presence of toxic adjuvants.

A further object of the invention is to provide a non-toxic composition of Paclitaxel that eliminates the use toxic adjuvants like liposomes, derivatives of emulsifying agents, amino acids that have known toxicity.

Yet another object of the invention is to provide a stable composition of Paclitaxel that ^' can be administered as bolus or a slow infusion of a free Paclitaxel.

Yet another object of the invention is to provide injectable composition of Paclitaxel that can be dispensed in ampoule or multidose vials, does not involve the use high technology for the preparation of parenterals, can be prepared in an ordinary manufacturing injectable plant and is thus more economical.

Yet another object of the invention is to provide a safer and stable composition of Paclitaxel that is therapeutically efficacious and has reduced chances of multi-dose resistance in the cancer cells.

It is a further object of the invention to provide a safer and stable Paclitaxel composition, which is economical and beneficial to use.

Summary of invention: Thus according to a first aspect of the present invention there is provided a novel stable composition of taxol comprising Paclitaxel and derivatives thereof; and 2,5 di-O-methyl 1 :3:4:6 dianhydroglucitol or analogs thereof.

According to a second aspect of the present invention, there is provided a process of preparing novel stable composition of taxol comprising providing a solvent consisting of 2,5 di-O-methyl 1 :3:4:6 dianhydroglucitol or analogs thereof and adding thereto Paclitaxel and derivatives thereof. Detailed Description:

The present inventors have formulated taxol compositions, which can be easily prepared as a stable formulation of Paclitaxel in a system comprising solubilizing Paclitaxel or its derivatives and 2,5 di-O-methyl 1 :3:4:6 dianhydroglucitol or its analogs thereof.

The present invention discloses preparation of Paclitaxel or derivatives thereof to be dissolved in 2,5 di-O-methyl 1:3:4:6 dianhydroglucitol or its analogs thereof and prepared in the concentration range of 0.2 mg/ml to 50 mg/ml yielding clear stable solution which can be administered as a slow bolus injection or through infusion pump or by parenteral administration admixing simultaneously online with saline or glucose. This is prepared in the concentration for the treatment of cancer at the rate desired by the oncologist.

The process can be executed at the plant scale as it has an advantage of solubility of Paclitaxel, low toxicity and renders better stability to the formulation.

This injection can be administered in the dose of 1 to 3-mg/70 kg to the patient and as advised by the doctor.

The natural pH of such solution would remain at about 4.0 to 5.5 leading to a stable solution requiring no use of extra acids for the adjustment of pH and the so prepared solution can be administered through Infusion pump delivering the consistent dose or as a bolus injection through micro syringe as desired by the oncologist.

The pump used in such administration procedure would be preferably a mechanized pump delivering less than the rate 0.1 ml to 99 ml/hr.

2,5 di-O-methyl 1 :3:4:6 dianhydroglucitol is purely synthetic in nature and hence does not lead to anaphylactic type reactions and has undergone pre-clinical toxicity studies proving its safety and good tolerance. 2,5 di-O-methyl 1:3:4:6 dianhydroglucitol is a liquid with a density of 1.16 and viscosity of about 5cps at 25°C. It is soluble in water and organic solvents in all proportions.

Structure of di-O-methyl 1:3:4:6 dianhydroglucitol is as follows:

wherein Rl and R2 are methyl groups.

The present invention discloses the use of preparation of taxol or derivative thereof which can be prepared in the concentration range of 0.2 mg/ml to 50 mg/ml in 2,5 di-O-methyl 1:3:4:6 dianhydroglucitol and can be administered through Intravenous route by bolus injection / through infusion pump delivering the desired dose and by concomitant administration of normal saline or dextrose normal saline.

The compositions in the dose of 0.2 mg/ml to 50 mg/ml of Paclitaxel can be prepared in 2,5 di-O-methyl 1 :3:4:6 di anhydroglucitol yielding a stable preparation. These are useful for the administration as a infusion/or bolus as desired by the oncologist. These compositions give a very safe, effective, economic and easy to prepare dosage forms of taxol and its derivatives in 2,5 di-O-methyl 1 :3:4:6 dianhydroglucitol or preparations of taxol which can be administered parenterally.

Solutions of Paclitaxel or its derivative may be prepared in the concentration of 0.2 mg to 50 mg/ml by taking the suitable quantities in a flask fitted with a stirrer and facility to flush the Nitrogen. The compound may be dissolved in di-O-methyl 1 :3:4:6 dianhydroglucitol in a suitable proportion by continuous stirring and necessary dilutions can further be made to achieve the final concentration.

The maximum solubility of Paclitaxel is found to be 50 mg/ml. Such advantage is not offered by any of the cited and searched prior art.

The solution may then be filled in glass ampoules/vials with bromo butylated rubber stopper for the clinical use. This procedure is carried out in hermetic condition aseptically after filtration through Nylon 66 0.22-micron filter.

The details of the invention, its objects and advantages are explained hereunder in greater detail in relation to non-limiting exemplary illustrations.

The examples are. merely illustrative and do not limit the teaching of this invention and it would be obvious to use taxol derivative, its isomers and additional suitable excipients like alcohol, solutol (Solutol HS 15), Polyethylene glycol 660 hydroxystearate, propylene glycol, glycerine or derivatives of Vit. E or Tocopherols and other excipients approved for the parenteral administration.

The miscibility of 2,5 di-O-methyl 1 :3:4:6 dianhydroglucitol for the preparation of such novel composition makes it easier to combine the injection with water and other lipophilic matrices.

Various modifications or changes in the formulations can be made by the persons skilled in the art and are encompassed within the ambit and spirit of this approach and scope thereof.

Examples :

1. 5.8554 mmole of Paclitaxel is taken in a flask filled with mechanism of stirring and attachment of nitrogen flushing. 50 ml of 2,5 di-O-methyl 1:3:4:6 dianhydroglucitol is added slowly and stirred for 30 minutes, further nitrogen is flushed and dissolved completely with additional 2,5 di-O-methyl 1 :3:4:6 dianhydroglucitol to make up to 100 ml. Filter aseptically through nylon 66 filter (0.2μ). The natural pH of the solution is about 5.3.

This is filled in amber ampoules or vials under hermetic condition.

2. 1.76 mmole of Paclitaxel is taken in a flask filled with mechanism of stirring and attachment of nitrogen flushing. 50 ml of 2,5 di-O-methyl 1 :3 :4:6 dianhydroglucitol is added slowly and stirred for 30 minutes, further nitrogen is flushed and the material is dissolved completely with additional 2,5 di-O-methyl 1:3:4:6 dianhydroglucitol to make up to 100 ml. Filter aseptically through nylon 66 filter (0.2μ).

The natural pH of the solution is about 5.3.

This is filled in amber ampoules or vials under hermetic condition.

3. 0.35132 mmole of Paclitaxel is taken in a flask filled with mechanism of stirring and attachment of nitrogen flushing. 50 ml of 2,5 di-O-methyl 1 :3:4:6 dianhydroglucitol is added slowly and stirred for 30 minutes, further nitrogen is flushed and dissolved completely with additional 2,5 di-O-methyl 1 :3:4:6 dianhydroglucitol to make up to 100 ml. Filter aseptically through nylon 66 filter (0.2μ).

The natural pH of the solution is about 5.3 determined potentiometrically. This is filled in amber ampoules or vials under hermetic condition.

4. 0.07026 mmole of Paclitaxel is taken in a flask filled with mechanism of stirring and nitrogen flushing. 50 ml of 2,5 di-O-methyl 1 :3:4:6 dianhydroglucitol is added slowly and stirred for 30 minutes, further nitrogen is flushed and dissolved completely with additional 2,5 di-O-methyl 1:3:4:6 dianhydroglucitol to make up to 100 ml. Filter aseptically through nylon 66 filter (0.2μ).

The above solutions are stable and tested by stability indicating HPLC method with the following parameters:

Column C₁₈ (4.6 mm x 25 cm) reversed phase. Column temperature : 25°C. Mobile phase: water : acetonitrile (11 : 9) Flow rate: 1.5 ml/min Wavelength of detection : 227 nm Injection volume : 10 μl

Composition of the present invention and the marketed preparation are compared for the pH, potency and impurity profile.

Innovative composition under review:

Paclitaxel 6 mg/ml in 2,5 di-O-methyl 1 :3:4:6 dianhydroglucitol

Marketed formulation composition: Paclitaxel 6 mg/ml, Polyoxyl 35 castor oil 527 mg, dehydrated alcohol 49.7% v/v/ml.

The results are given in the below table. Table- 1

Additionally periodic stability was carried out for the compositions under review and the data is tabulated in the following manner:

PERIODIC STABILITY STUDY

Table-2

Name of the product Paclitaxel Injection, 6 mg/m Batch no. PD-EXP A I Batch size 100 ml, 1 ml ampoules Mfg. Date August, 2003 Storage condition A 8° C

Sr. Test Specification Initial 1 2 3 No. Months Months Months 1 Description Clear, colon rless Complies Complies Complies Complies liquid

2 Assay 90% - 110% 101.55 % 100.82 % 99.99 % 99.78 % PERIODIC STABILITY STUDY

Table-3 Name of the product Paclitaxel Injection , 6 mg/ml Batch no. PD-EXP A II Batch Size 100 ml, 1 ml ampoules Mfg. Date August, 2003 Storage condition At 8° C

PERIODIC STABILITY STUDY Table-4

Name of the product Paclitaxel Injection , 6 mg/ml Batch no. PD-EXP A III Batch Size 100 ml, 1 ml ampoules Mfg. Date August, 2003 Storage condition At 8° C

PERIODIC STABILITY STUDY

Table-5

Name of the product Paclitaxel Injection, 6 mg/ml Batch no. PD-EXP A I Batch size 100 ml, 1 ml ampoules Mfg. Date August, 2003 Storage condition At 25° C ± 2°C /60 ± 5% RH

PERIODIC STABILITY STUDY Table-6 Name of the product Paclitaxel Injection, 6 mg/ml Batch no. PD-EXP A II Batch Size 100 ml, 1 ml ampoules Mfg. Date August, 2003 Storage condition At 25° C ± 2°C /60 ± 5% RH

PERIODIC STABILITY STUDY

Table-7

Name of the product : Paclitaxel Injection, 6 mg/ml Batch no. : PD-EXP A III Batch Size 100 ml, 1 ml ampoules Mfg. Date : August, 2003 Storage condition : At 25° C ± 2°C /60 ± 5% RH

Sr. Test Specification Initial 1 2 3

No. Months Months Months

1 Description Clear, colourless Complies Complies Complies Complies liquid

3 Assay 90% - 110% 101.64 % 101.49 % 101.31 % 100.98 %

ACCELERATED STABILITY STUDY Table-8

Name of the product Paclitaxel Injection, 6 mg/ml Batch no. PD-EXP A I Batch size 100 ml, 1 ml ampoules Mfg. Date August, 2003 Storage condition At 30° C ± 2°C /60 ± 5% RH.

ACCELERATED STABILITY STUDY

Table-9 Name of the product Paclitaxel Injection , 6 mg/ml Batch no. PD-EXP A II Batch Size 100 ml, 1 ml ampoules Mfg. Date August, 2003 Storage condition At 30° C ± 2°C /60 ± 5% RH

ACCELERATED STABILITY STUDY Table- 10 Name of the product : Paclitaxel Injection , 6 mg/ml Batch no. : PD-EXP A III Batch Size 100 ml, 1 ml ampoules Mfg. date : August, 2003 Storage condition : At 30° C ± 2°C 160 ± 5% RH

From the above stability studies it is indicated that the inventive and novel compositions of Paclitaxel in the concentration of 0.2 mg/ml to 50 mg/ml are stable when prepared in 2,5 di-O-methyl 1:3:4:6 dianhydroglucitol or its analogs.

Claims

1. Novel stable composition of taxol comprising Paclitaxel and derivatives thereof; and 2,5 di-O-methyl 1 :3:4:6 dianhydroglucitol or analogs thereof.

2. Novel stable composition of taxol as claimed in claim 1 wherein the composition is in the form of a solution in the concentration range of 0.2mg/ml to 50 mg/ml.

3. Novel stable composition of taxol as claimed in claims 1 and 2 wherein the solution is filled in the ampoules or suitable vials hermetically.

4. Novel stable composition of taxol as claimed in claims 1 to 3 wherein the solution is administered as a bolus injection using micro syringe or through infusion pump.

5. Novel stable composition of taxol as claimed in claim 4 wherein the injection is dispensed in ampoules and vials or suitable administrative device like pre-filled syringes or for the buccal, parenteral, local or through any gastrointestinal route.

6. Process of preparing novel stable composition of taxol as claimed in any of the preceding claims comprising providing a solvent consisting of 2,5 di-O-methyl 1:3:4:6 dianhydroglucitol or analogs thereof and adding thereto Paclitaxel and derivatives thereof.