COMPLEXES OF SIROLIMUS AND ITS DERIVATIVES, PROCESS FOR THE PREPARATION THEREOF AND PHARMACEUTICAL COMPOSITIONS CONTAINING THEM

Abstract

The invention is directed to a stable complex with controlled particle size, increased apparent solubility and increased dissolution rate comprising as active compound Sirolimus or derivatives thereof, which is useful in the prophylaxis of organ rejection in patients receiving renal transplants, in the treatment of psoriasis, facial angiofibromas associated with tuberous sclerosis, fibrofolliculomas found in Birt-Hogg-Dub Syndrome, chronic erosive oral lichen planus, Early Stage Cutaneous T-cell Lymphoma, Treatment of Autoimmune Active Anterior Uveitis, dry eye syndrome, age-related macular degeneration, diabetic macular edema, noninfectious uveitis, telangiectasia, inflammatory skin diseases (dermatitis, including psoriasis and lichen ruber planus), Pachyonychia Congenita and in the suppression of angiogenesis pathways. More specifically, the complex of the present invention possesses increased apparent solubility, permeability and enhanced biological performance including significantly improved exposure, earlier tmax, higher Cmax and higher trough concentrations at 24 hours which will allow the reduction of the dose.

Claims

1. A stable complex comprising as active compound selected from the group of Sirolimus, its salts or derivatives thereof; and at least one complexing agent selected from the group of polyvinylcaprolactam-polyvinyl acetate-polyethylene-glycol graft copolymers; poloxamers; polyvinylpyrrolidone; copolymers of vinylpyrrolidone and vinyl-acetate; and poly(maleic acid-co-methyl-vinyl-ether); said complex characterized in that it possesses at least one of the following properties: a) has a particle size in the range between 50 nm and 600 nm, preferably 50 nm and 200 nm b) is instantaneously redispersable in physiological relevant media; c) has increased dissolution rate; d) is stable in solid form and in colloid solution and/or dispersion; e) has a PAMPA permeability of at least 2.0*10.sup.6 cm/s, which does not decrease in time at least for 1 month; f) has characteristic infrared (ATR) and or Raman absorption peaks/bands; g) said complex has decreased fed/fasted effect; h) said complex has significantly improved exposure, earlier t.sub.max, higher C.sub.max and higher trough concentrations at 24 hours which will allow the reduction of the dose, i) said complex faster onset of action; and j) said complex possibility of the development of liquid based formulation for transdermal and other topical applications based on stability of the formula in liquid form.

2. The complex according to claim 1, wherein said complexing agent is selected from the group of polyethylene glycol glycerides composed of mono-, di- and triglycerides and mono- and diesters of polyethylene glycol, hydroxypropylcellulose, poloxamers (copolymers of ethylene oxide and propylene oxide blocks), vinylpyrrolidone/vinyl acetate copolymer, Polyethylene glycol, poly(2-ethyl-2-oxazoline), polyvinylpyrrolidone, block copolymers based on ethylene oxide and propylene oxide, poly(maleic acid/methyl vinyl ether), (polyvinyl caprolactam-polyvinyl acetate-polyethylene glycol graft copolymer, polyoxyl 15 hydroxystearate, ethylene oxide/propylene oxide block copolymer, and d-alpha tocopheryl polyethylene glycol 1000 succinate, preferable the complexing agent is a polyvinylpyrrolidone.

3. The complex according to claims 1 or 2, wherein said complex further comprises at least one pharmaceutically acceptable excipient selected from the group of sodium-lauryl-sulfate and sodium-acetate, preferable the pharmaceutically acceptable excipient is sodium-lauryl-sulfate.

4. The complex according to any of claims 1 to 3, wherein said complex further comprises one or more additional active agents, preferable the additional active agent is selected from the group of agents useful for the prophylaxis of organ rejection in patients receiving renal transplants, for the treatment of psoriasis, facial angiofibromas associated with tuberous sclerosis, fibrofolliculomas found in Birt-Hogg-Dub Syndrome, chronic erosive oral lichen planus, Early Stage Cutaneous T-cell Lymphoma, Treatment of Autoimmune Active Anterior Uveitis, dry eye syndrome, age-related macular degeneration, diabetic macular edema, noninfectious uveitis, telangiectasia, inflammatory skin diseases (dermatitis, including psoriasis and lichen ruber planus), Pachyonychia Congenita and for the suppression angiogenesis pathways.

5. A stable complex according to any of claims 1 to 4 comprising an active compound selected from the group of Sirolimus, its salt, or derivatives thereof; at least one complexing agent selected from the group of polyvinylcaprolactam-polyvinyl acetate-polyethylene-glycol graft copolymers; poloxamers; polyvinylpyrrolidone; copolymers of vinylpyrrolidone and vinyl-acetate; and poly(maleic acid-co-methyl-vinyl-ether); and at least one pharmaceutically acceptable excipient chosen from sodium-lauryl-sulfate and sodium-acetate; wherein said complex obtained via a mixing process, preferable continuous flow mixing process, more preferable microfluidic flow mixing process.

6. A complex according to any of claims 1 to 5 comprising a complexing agent which is a polyvinylpyrrolidone and a pharmaceutically acceptable excipient which is sodium-acetate, in a total amount ranging from about 1.0 weight % to about 95.0 weight % based on the total weight of the complex.

7. A process for the preparation of the complex according to any of claims 1 to 6, comprising the steps of mixing a solution of Sirolimus, its salt, or derivatives thereof, and at least one complexing agent selected from the group of polyvinylcaprolactam-polyvinyl acetate-polyethylene-glycol graft copolymers; poloxamers; polyvinylpyrrolidone; copolymers of vinylpyrrolidone and vinyl-acetate; and poly(maleic acid-co-methyl-vinyl-ether) in a pharmaceutically acceptable solvent with an aqueous solution containing at least one pharmaceutically accepted excipient chosen from sodium-lauryl-sulfate and sodium-acetate.

8. The process according to claim 7, wherein said process is performed in a continuous flow instrument, preferable in microfluidic instrument.

9. The process according to claims 7 or 8, wherein said pharmaceutically acceptable solvent is selected from the group of methanol, ethanol, isopropanol, n-propanol, acetone, acetonitrile, dimethyl-sulfoxide, tetrahydrofuran, and combinations thereof, preferable the solvent is methanol.

10. The process according to any of claims 7 to 9, wherein the solvent and the aqueous solvent are miscible with each other and the aqueous solvent comprises 0.1 to 99.9% weight of the final solution.

11. A pharmaceutical composition comprising the complex according to any of claims 1 to 6 together with pharmaceutically acceptable carrier.

12. A pharmaceutical composition according to claim 11, wherein said composition is suitable for oral, pulmonary, rectal, colonic, parenteral, intracisternal, intravaginal, intraperitoneal, ocular, otic, local, buccal, nasal, or topical administration, preferable the composition is suitable for oral and topical administration.

13. A complex according to any of claims 1 to 6 for use in the manufacture of a medicament for the prophylaxis of organ rejection in patients receiving renal transplants, for the treatment of psoriasis, facial angiofibromas associated with tuberous sclerosis, fibrofolliculomas found in Birt-Hogg-Dub Syndrome, chronic erosive oral lichen planus, Early Stage Cutaneous T-cell Lymphoma, Treatment of Autoimmune Active Anterior Uveitis, dry eye syndrome, age-related macular degeneration, diabetic macular edema, noninfectious uveitis, telangiectasia, inflammatory skin diseases (dermatitis, including psoriasis and lichen ruber planus), Pachyonychia Congenita and for the suppression angiogenesis pathways.

14. The use of the complex according to any of claims 1 to 6 for the prophylaxis of organ rejection in patients receiving renal transplants, for the treatment of psoriasis, facial angiofibromas associated with tuberous sclerosis, fibrofolliculomas found in Birt-Hogg-Dub Syndrome, chronic erosive oral lichen planus, Early Stage Cutaneous T-cell Lymphoma, Treatment of Autoimmune Active Anterior Uveitis, dry eye syndrome, age-related macular degeneration, diabetic macular edema, noninfectious uveitis, telangiectasia, inflammatory skin diseases (dermatitis, including psoriasis and lichen ruber planus), Pachyonychia Congenita and for the suppression angiogenesis pathways.

15. A method of prophylaxis of organ rejection in patients receiving renal transplants, treatment of psoriasis, facial angiofibromas associated with tuberous sclerosis, fibrofolliculomas found in Birt-Hogg-Dub Syndrome, chronic erosive oral lichen planus, Early Stage Cutaneous T-cell Lymphoma, Treatment of Autoimmune Active Anterior Uveitis, dry eye syndrome, age-related macular degeneration, diabetic macular edema, noninfectious uveitis, telangiectasia, inflammatory skin diseases (dermatitis, including psoriasis and lichen ruber planus), Pachyonychia Congenita and for the suppression angiogenesis pathways comprising administration of a therapeutically effective amount of the complex according to any of claims 1 to 6 or the pharmaceutical composition according to claim 11 or 12.

16. A method for reducing the therapeutically effective dosage of Sirolimus compared to commercially available oral dosage forms, said method comprising oral administration of a pharmaceutical composition according to claims 11 or 12.

17. A stable complex comprising a) 10-40% by weight of Sirolimus, its salt, or derivatives thereof; b) 20-80% by weight of a polyvinylpyrrolidone; and c) 5-50% by weight of sodium-lauryl-sulfate wherein said complex has a controlled particle size in the range between 50 nm and 600 nm, preferable the particle size is between 50 nm and 200 nm; and wherein said complex is obtained according to any of claims 7 to 10.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0099] FIG. 1. shows the complexing agent screening for formula selection in order to select the formulae having instantaneous redispersibility

[0100] FIG. 2. shows Comparative PAMPA assays of the unformulated compound, complex Sirolimus formula, marketed oral solution and marketed tablet form dispersed in different media

[0101] FIG. 3. shows PAMPA permeability of solid complex Sirolimus formula stored at 4 C., room temperature or 40 C. 75% relative humidity right after redispersion and at different time points (1, 7, 14, 34 and 95 days after the production)

[0102] FIG. 4. shows PAMPA permeability of colloid solution of complex Sirolimus formula stored at 4 C., room temperature or 40 C. 75% relative humidity and at different time points (1, 7, 14, 34 and 95 days after the production)

[0103] FIG. 5. shows plasma concentration of Sirolimus following the oral administration of the marketed drug (Rapamune tablet) and Sirolimus complex to rats under the fasting conditions (n=4, dose: 1.0 mg/kg)

[0104] FIG. 6. shows pharmacokinetic parameters following the oral administration of the marketed drug (Rapamume tablet) and the Sirolimus complex to rats under the fasting conditions (n=4, dose: 1.0 mg/kg)

[0105] FIG. 7. shows dissolution test of capsule containing complex Sirolimus

EXAMPLES

[0106] Several pharmaceutically accepted complexing agents and pharmaceutically accepted excipients and their combinations were tested in order to select the formulae having instantaneous redispersibility as shown in FIG. 1. One of the examples that displayed an acceptable level of redispersibility was selected for further analysis.

[0107] Polyvinylpyrrolidone as complexing agent and sodium-lauryl sulfate as pharmaceutically accepted excipient were selected to form complex Sirolimus formulation having improved material characteristics.

[0108] The ratio of the selected complexing agent and pharmaceutically accepted excipient (polyvinylpyrrolidone and sodium-lauryl sulfate) was optimized making some slight differences in the preparation process to modify some characteristics of the product.

[0109] Colloid solution of Sirolimus complex formula of the present invention was prepared by continuous flow precipitation in a flow instrument. As a starting solution, 100 mg Sirolimus and 300 mg polyvinylpyrrolidone (PVP K90) dissolved in 100 mL methanol was used. The prepared solution was passed into the instrument with 5 mL/min flow rate. Meanwhile, antisolvent containing 250 mg sodium-lauryl sulfate in 500 mL water was passed into the instrument with 20 mL/min flow rate, where Sirolimus was precipitated to form complex Sirolimus composition. The colloid solution of the complex Sirolimus is continuously produced at atmospheric pressure. The produced colloid solution was frozen on dry-ice and then it was lyophilized using Scanvac CoolSafe 110-8 freeze drier equipped with 110 C. ice condenser, with a Vacuubrand RZ6 vacuum pump.

[0110] In order to make the production process industrially feasible, process intensification was performed by increasing the concentrations of the starting solution. A colloid solution of Sirolimus complex formula of the present invention was prepared by continuous flow mixing in a flow instrument using the intensified process parameters. As a starting solution, 1000 mg Sirolimus and 3000 mg polyvinylpyrrolidone (PVP K90) dissolved in 100 mL methanol was used. The prepared solution was passed into the instrument with 10 mL/min flow rate. Meanwhile, aqueous solvent containing 2500 mg sodium-lauryl sulfate in 500 mL water was passed into the instrument with 40 mL/min flow rate, where Sirolimus formed complex Sirolimus composition.

Comparative In Vitro PAMPA Assays

[0111] PAMPA permeability measurements were performed as described by M. Kansi et al. (Journal of medicinal chemistry, 41, (1998) pp 1007) with modifications based on S. Bendels et al (Pharmaceutical research, 23 (2006) pp 2525). Sample containing the reference compound or the marketed drug were a suspension of crystals visible by the naked eye, while samples of the novel complex were opalescent colloid solutions. Permeability was measured in a 96-well plate assay across an artificial membrane composed of dodecane with 20% soy lecithin supported by a PVDF membrane (Millipore, USA). The receiver compartment was phosphate buffered saline (pH 7.0) supplemented with 1% sodium dodecyl sulfate. The assay was performed at room temperature; incubation time was 1-24 hours. The concentration in the receiver compartment was determined by UV-VIS spectrophotometry (Thermo Scientific Genesys S10).

[0112] PAMPA permeability of complex Sirolimus formula of the present invention and the marketed drug was in the 2-6*10.sup.6 cm/s range, while marketed Rapamune tablet exhibited at least 50% lower permeability when dispersed in water or in biorelevant media. The oral solution and the reference compound exhibited lower than 1*10.sup.6 cm/s permeability in all dispersing media tested (FIG. 2).

Stability of the Complex Sirolimus

[0113] The solid forms and the redispersed colloid solutions were subjected to stability tests at 4 C., room temperature or 40 C. 75% relative humidity for up to three months. The solids redispersed at the indicated time points exhibited no change in PAMPA permeability under any of the storage conditions (FIG. 3). The redispersed colloids did not show significant change in PAMPA permeability for up to a month under all conditions, while no change was observed at 4 C. or room temperature for up to 3 months (FIG. 4).

In-Vivo Pharmacokinetics

In-Vivo PK Test in Small Animals

[0114] Male Wistar rats (250-270 g) were treated orally with either the test article or the reference article (1.0 mg/kg) one time via esophageal gavage technique following overnight fasting. Whole blood was sampled from the saphenous vein into heparinized tubes (approx. 0.2 mL to each tube) before and at 0.5, 1, 2, 3, 4, 6, 8, 24, and 48 hours after the oral administration of the test or reference articles. Whole blood samples were stored at minus 20 C. until analysis. Sirolimus concentrations were determined from whole blood samples by an LC-MS/MS technique.

[0115] Pharmacokinetic data were expressed as measured values and as normalized values. Measured values were normalized to the extraction recovery of the standard solution from whole blood. Extraction recovery of the standard solution from whole blood varied between 94.0 and 114.7%. Following oral administration of Sirolimus as Sirolimus complex formula, t.sub.max was significantly decreased whilst C.sub.max and AUC values increased when compared to the marketed tablet form, Rapamune. The trough concentrations measured as blood Sirolimus levels at 24 hours were also increased over 2-fold when compared to Rapamune (FIG. 5-6).

Pharmaceutical Development

Production of Intermediate Drug Product of Complex Sirolimus Formula

[0116] Intermediate drug product was produced by mixing solid complex Sirolimus formula and commercially available excipient, Cellactose 80 composing of 75% wt % lactose monohydrate and 25 wt % microcrystalline cellulose in the bracketing range of 0.5 and 2.0 mg strengths. For the production of intermediate drug product with 0.5 mg strength 9.23% wt % solid complex Sirolimus formula and 89.77% wt % Cellactose 80 were mixed, while for 2.0 mg strength 1.67% wt % solid complex Sirolimus formula and 97.33% wt % Cellactose 80 were mixed, respectively. Both powder mixtures were lubricated with 1% wt % magnesium stearate and filled into 1 size hard gelatin capsules. The powder mixture showed good flowability (USP <1174> and Ph. Eur. 2.9.16).

In-Vitro Dissolution Tests

[0117] Dissolution test was performed by paddle method (Vankel VK7000) at 120 rpm and 37 C. Dissolution media was distilled water with 0.4% SLS (recommended by FDA). The concentration of Sirolimus was detected by UV-VIS spectrophotometry after filtration with a 1 m pore size syringe filter at 279 nm wavelength. Complete dissolution of complex Sirolimus from the intermediate drug product was observed within 10 minutes (FIG. 7).

Preparation of Topical Gel Formulation of Complex Sirolimus Formula

[0118] A gel formula for topical administration was developed using the novel complex Sirolimus formula. The gel was prepared by the sequential addition of the following components under continuous stirring: 1.800 g glycerol, 2.250 g 1 mg/ml sorbic acid solution, 3.828 g distilled water, 0.045 g Carbopol CP980 (as solid), 0.180 g 1 M sodium hydroxide solution and 0.900 g of the novel complex Sirolimus formula redispersed in distilled water at 10 mg/g concentration for active content.