WO1995003063A1

WO1995003063A1 - Oral pharmaceutical compositions comprising reduced glutathion

Info

Publication number: WO1995003063A1
Application number: PCT/EP1993/001947
Authority: WO
Inventors: Ferdinando Ventra
Original assignee: Esseti S.A.S. Laboratorio Chimico Farmaco Biologico Di A. Ievoli & C.
Priority date: 1993-07-22
Filing date: 1993-07-22
Publication date: 1995-02-02
Also published as: AU4701593A

Abstract

Oral pharmaceutical compositions comprising an effective amount of GSH and a gastroresistant and enterosoluble material optionally in admixture with other conventional excipients are described.

Description

ORAL PHARMACEUTICAL COMPOSITIONS COMPRISING REDUCED GLUTATHION

The present invention refers to oral pharmaceutical compositions containing as the active principle the tripeptide N-(N-l-V^-glutamyl-l- cisteinyDglycine, known as reduced glutathion (GSH) .

GSH is a physiological substance widespread in the living body where it is involved in a number of biological processes. Its pharmacological use has been througly investigated and it is presently available in parenteral pharmaceutical compositions for the treatment of ethanol intoxication or for the prevention or treatment of toxic effects induced by some drugs (chemotherapeutic agents, antitubercolar agents, neuroleptics, paracetamol, antidepressants) as well as for the prophylaxis and treatment of damages induced by ionizing radiations.

These therapeutic activities may be due to the anti-oxidizing activity of GSH. It is in fact known that lipoperoxidative processes, responsible for cellular necrosis, are made easier in case of GSH deficit.

The peptide nature of GSH and the presence of the free SH group, which can be easily oxidized to disulfide, have until now limited the administration routes only to the parenteral one. It has been reported that, by oral administration, it is not possible to increase the serum concentration of GSH.

We have now surprisingly found that GSH serum levels not only comparable to that obtainable after parenteral administration but even more prolonged in time, can be obtained by means of oral pharmaceutical compositions comprising suitable excipients, which can protect GSH during the passage through the stomach making it available for absorption in the first tract of bowel (proximal intestine), where GSH is rapidly absorbed before being inactivated by oxidizing agents and/or proteolytic enzymes.

The compositions of the invention comprise an effective amount of GSH, and a gastroresistant and enterosoluble material optionally in admixture with other conventional excipients.

According to a preferred embodiment of the invention, the compositions also include a pharmaceutically acceptable anti-oxidizing agent and/or a pharmaceutically acceptable ionic or non-ionic surfactant.

The presence of at least one surfactant increases the already remarkable bioavailability and pharmacokinetic characteristics of the compositions of the invention, characterized by serum concentrations prolonged up to 24 hours after single administration. Preferred surfactants are non-ionic surfactants such as polyoxyalkylene ethers of higher alcohols, particularly those corresponding to the general formula I

R0((CH₂)_n0)_χH (I) wherein RO represents the residue of an higher alcohol, particularly an higher alkanol or an alkylphenol such as lauric or cetyl alcohol, or a sterolic residue, particularly lanosterol, dihydrocholesterol or cholesterol, as well as mixtures thereof. The preferred polyoxyalkylene ethers are polyoxyethylene and polyoxypropylene ethers (n = 2 or 3), particularly lauric, cetyl or cholesteryl ethers or mixtures thereof. The hydroxy group at the end of the polyoxyalkylene chain can be partially or completely acylated for instance with acyl residues of aliphatic carboxylic acids such as acetic acid. The preferred ethers have an HLB value (hydrophilic/lipophilic balance) ranging from about 10 to about 20, especially from about 12 to about 16. The particularly suitable ethers are those wherein the average number of the sequences in the polyoxyalkylene residue (x in the above formula) ranges from 4 and 75, advantageously from 8 and 30, more particularly from 16 and 26. Said ethers are commercially available under the trade-marks Solulan (KAO Soap), Emalex, Brij, Laureth, Cetomacrogol, or they can be obtained by known methods. Alternatively, ionic surfactants may also be used, such as quaternary ammonium salts (e.g. benzalkonium chloride), betaines, alkylbetaines, alkylamido propylbetaines, sodium dodecylsulfate.

Particularly preferred are natural surfactants such as lecithins (from soy-bean or egg) which are particularly effective in promoting the absorption of the active principle.

The surfactants are comprised in the compositions of the invention in ratios ranging from 0.01 to 50 parts of surfactant per 100 parts of GSH. Any known substance imparting gastro-resistance may be conveniently used in the formulations of the invention: typical examples include cellulose acetophthalate, Eudragit'^R' L and S; polymethacrylic acid (38%) polyvinylacetate (46,7%) - stearic acid (7,6%) tetrahydrofuryl oleate (7,7%) mixture; lac gum and the like. These substance may be applied by means of known coating techniques according to the different dosage forms, such as tablets, sugar-coated tablets, hard or soft gelatine capsules, granules distributed in sachets or capsules granules in ready-to-use or extemporaneous mono- or multi-dose suspension.

Suitable anti-oxidant agents which may be conveniently used are ascorbic acid, thiopropionic acid, 1-ascorbyl palmitate, tocopherols (alfa, gamma, delta or mixtures), in ratios ranging from 0.01 to 100 parts by weight per 100 parts of GSH.

Other conventional excipients may be used in the formulations of the invention such as lubricants, buffers, flavours, diluents, disgregating agents, etc.

The pH of oral liquid compositions is preferably comprised from 3.5 to 4.5. The liquid carrier is preferably water.

The compositions of the invention contain unit doses ranging from 10 to 5.000 mg of GSH. The following examples further illustrate the invention. Example 1 (reference example)

Non-gastroresistant tablets containing 1200 mg of GSH

Composition

GSH mg 1260.00 (+5%)

Ascorbic acid mg 25.00 Soy lecithin mg 21.50

Lactose mg 25.00 Avicel PH 102 mg 30.00

Maize starch mg 30.00

Mg stearate mg 10.00

Talc mg 15.00 Titanium dioxide mg 2.50

Preparation of 1000 tablets

1200 g of GSH, 25 g of ascorbic acid, 21.5 g of soy lecithin, 25 g of lactose, 30 g of Avicel PH 102,

30 g of maize starch, 15 g of talc and 2,50 g of titanium dioxide are mixed in a dehumidified room (max

35% relative humidity) until complete homogenization.

10 g of Mg stearate are added and mixing is continued for further 10 minutes. The powder mixture is tabletted to give tablets weighting 1400 g. Example 2

Capsules containing gastroresistant granules

Composition

GSH mg 600.00

Tocopherols mg 18.00 Lanoline alcohol ethers mg 18.00

Sucrose mg 50.00

Polyvinylpyrrolidone mg 10.00

Magnesium stearate mg 15.00

Titanium dioxide mg 1.50 Lac gum mg 40.00

Preparation of 1000 capsules

600 g of GSH, 18 g of tocopherols (mixture), 18 g of lanoline alcohol ethers, 50 g of finely ground sucrose, 10 g of PVP and 15 g of Mg stearate are thoroughly mixed. The mixture is then tableted to give small 15 mg tablets which are then coated in fluid bed with a solution of lac gum in 100 ml of ethanol.

The small tablets, after coating with a layer of titanium dioxide until constant weight, are distributed in hard gelatine capsules type N. 0 at the dose of 755 mg + 5%. Gastroresistance was measured according to standard Pharmacopeia tests: resistance in 0.10 N HC1:

> 2 h. Complete dissolution in phosphate buffer pH 6.80 10 minutes.

Example 3 Sugar coated tablets

Composition

GSH mg 300.00

Maize starch mg 98.80

Lactose mg 81.50 Microgranular cellulose mg 45.00

Precipitated silica mg 25.00

Ascorbic acid mg 15.00

Soy lecithin mg 10.00

Magnesium stearate mg 5.00 PVP mg 15.00

Sucrose mg 120.00

Cellulose acetate phthalate mg 26.00

Titanium dioxide (E 131) mg 5.30

Polyethylenglycol 6000 mg 0.30 Quinoline yellow (E 104) mg 0.50

White wax mg 0.075

Carnauba wax mg 0.075

Process

Soy lecithin, ascorbic acid and GSH are added to wet silica; the mixture is kneaded and granulated through 2 mm sieve. After drying at 50°C for 30 min., the granulate is sieved through 1 mm sieve. Similarly, a granulate is obtained from maize starch and lactose, by dispersing maize starch in water at 95°C. The two granulates are mixed together with Mg stearate and microgranular cellulose and then tabletted to give tablets weighing 570 mg + 5%. The tablets are then coated with:

PVP in ethanol and talc, up to 590 mg; sucrose, talc, maize starch, titanium dioxide in water up to 628 mg;

- cellulose acetophthalate and butyl phthalate in

CH₂C1₂ and ethanol, dusting with Mg stearate, up to 670 mg;

PVP in CH₂ci₂ and ethanol, dusting with talc, up to 685 mg; sucrose, talc, maize starch, titanium dioxide and yellow quinoline up to 730 mg; sucrose and PEG in ethanol up to 739 mg; white wax and carnauba wax in CH₂C1₂ to the final weight of 745 mg.

Example 4 Extemporaneous suspension

3 g of GSH in 60,4 g of powder for the preparation of 100 ml of oral suspension. Preparation for 100 bottles

300 g of GSH are coated in fluid bed with 300 ml of a solution having the following composition under nitrogen atmosphere:

1-ascorbyl palmitate mg 0.90 Lauryl alcohol ether (Brij^(R)35) mg 0.90

Diethylphthalate mg 15.00 Cellulose acetophthalate mg 50.00

Methylene chloride q.s. to mg 300.00

The obtained homogeneously coated GSH particles are then mixed with 200 g of sucrose, 100 g of carboxymethylcellulose, 1 g of flavour, 8 g of citric acid, 0,5 of glycamyl and 0.010 g of antifoam. The mixture is distributed into 100 ml bottles in amount of 60.4 g/bottle.

Example 5 Ready-to-use suspension containing 300 mg of GSH in 10 ml Preparation of 100 bottles

383 g of GSH coated as in Example 4, equivalent to 300 g of GSH are mixed with a suspension of 5 g of CMC, 2.8 of methylparaoxybenzoate, 1.20 g of propylparaoxybenzoate, 10 g of citric acid and 10 g of cherry flavour in 5 1 of sucrose syrup. After strong agitation, the final volume is adjusted to 1 10 with sucrose syrup.

Example 6 GSH gastroresistant microgranules A. Granulation 10 kg of finely ground GSH are coated with a mixture having the following composition:

Eudragit^(R) L 30 D g 2160

Talc g 324

Triethyl citrate g 64

Soy lecithin g 32 Ascorbyl palmitate g 32

Tween 80 g 32 Water g 3026

B. Coating

The homogeneous granulate obtained in A is coated with the following mixture: Eudragit^(R) g 6500

Talc g 175

Triethyl citrate g 195

Water g 7930

The coated granulate gives the following results at the gastro-resistance and enterosolubility tests:

Resistance in 0.10 NHC1: > 2 h

Complete dissolution in phosphate buffer pH 6.80: <_ 10 min.

Example 7 Sachets containing 1200 mg of GSH

Composition

Each 6 g sachet contains:

Coated GSH mg 1467.20 equivalent to 1200 mg GSH

1-ascorbyl palmitate mg 3.60 Methacrylic acid copolymer (Eudragit L 30 D) mg 200.00

Talc mg 60.00

Triethyl citrate mg 3.60;

SDS (sodium dodecylsulfate) mg 5.00

Glycamyl mg 50.00 Carboxymethylcellulosa sodium mg 500.00

Anhydrous citric acid mg 150.00

Flavour mg 500

Laevulose mg 2883

Preparation of 5000 sachets 250 g of glycamyl, 2.5 kg of CMC, 750 g of citric acid and 14.415 kg of Laevulose are mixed in a dehumidified environment in stainless steel mixer.

The mixture is then kneaded with ethanol containing the flavour. The granulate is made homogeneous, dried, sieved and mixed with 7.336 kg of coated GSH continuing mixing for at least 35-40' until complete homogenization.

Example 8

Unit-dose oral liquid formulation (600 mg GSM; bottle with reservoir cap) Composition

Each cap contains:

GSH mg 600

1-ascorbyl palmitate mg 1.80

Glycamyl mg 4.00 Eudragit L30 D mg 60.00

Soy lecithin mg 2.55

Talc mg 30.00

Triethyl citrate mg 6.00

Na carboxymethylcellulose mg 60.00 Each 15 ml bottle contains:

Na methylparabenzoate mg 2.80

Na propylparabenzoate mg 1.20

Laevulose g 4.00

Citric acid mg 1.50 Rhubarb extract mg 375.00

Sweet orange tincture mg 90.00

Artichoke extract mg 15.00

Purified water q.s. to 15 ml

Preparation Laevulose, antibacterial agents, citric acid and flavours are dissolved in about 70% of water. After adjusting to the final volume with water, the syrup is filtered and distributed into the bottles. The GSH microgranules obtained in the previous examples are mixed with Na CMC and distributed into the caps at the dose of 792 mg ± 20%. The final dosage form is obtained by conventional methods and apparatuses.

Example 9 Sachets containing 1200 mg of GSH Composition Coated GSH mg 1467.20 equivalent to GSH mg 1200

Soy lecithin mg 3.60

Methacrylic acid copolymer (Eudragit L 30 D) mg 200.00 Talc mg 60.00

Triethyl citrate mg 3.60 Glycamyl mg 50.00

Sodium CMC mg 500.00

Anhydrous citric acid mg 150.00

Flavour mg 500

Laevulose mg 2883 The preparation was carried out as in Example 7.

Example 10 Unit-dose oral liquid formulation (GSH 600 mg; bottle with reservoir cap)

The reservoir contains: GSH mg 600

Ascorbyl palmitate mg 1.80

Glycamyl mg 4.00

Eudragit L 30 D mg 60.00

Talc mg 30.00 Triethyl citrate mg 6.00

Na carboxymethylcellulose mg 60.00 The 15 ml bottle contains: Na methylparabenzoate mg 2.80 Na propylparabenzoate mg 1.20 Laevulose g 4.00 Citric acid mg 1.50

Rhubarb extract mg 375.00 Sweet orange tincture mg 90.00 Artichoke extract mg 15.00 Purified water q.s. to ml 15.00 The preparation was carried out as in Example 8.

Example 11 Sachets containing 1200 mg of GSH Composition

Coated GSH mg 1463.60 equivalent to GSH mg 1200 Methacrylic acid copolymer (Eudragit L 30 D) mg 200.00 Talc mg 60.00

Triethyl citrate mg 5.00

Glycamyl mg 50.00

Sodium CMC mg 500.00 Anhydrous citric acid mg 150.00

Flavour mg 500

Laevulose mg 2883

The preparation was carried out as in Example 7.

Example 12 Pharmacokinetics test

12 Healthy volunteers (6 males and 6 females) were administered with the compositions of Examples 3, 4 and

6 and with injectable vials at the dose of 1200 mg GSH, according to cross-over administration scheme, with a 1 week wash out period between treatments.

Blood samples were taken after 0.05, 1, 1.5, 2, 4, 6, 8, 12 and 24 hours after the single administration. The GSH plasma levels were determined by HPLC according to the method of Reed et al. (Anal. Biochem. 106, 55, 1980). The results obtained, reported in Figure 1, clearly show that the absorption degree, evaluated by the area under the curve in the period 0-24 hours (AUC 0-24 hours) is much higher for the oral compositions of the invention in comparison to that of injectable vials.

Significant blood concentrations were detectable after 24 hours after the administration of the oral compositions. The coated compositions gave slightly better results than non-coated compositions.

Claims

1. Oral pharmaceutical compositions comprising an effective amount of GSH and a gastroresistant and enterosoluble material optionally in admixture with other conventional excipients.

2. Pharmaceutical compositions according to claim 1 further comprising a pharmaceutically acceptable anti- oxidizing agent and/or a pharmaceutically acceptable ionic or non-ionic surfactant.

3. Pharmaceutical compositions according to claim 2 comprising non-ionic surfactants.

4. Pharmaceutical compositions according to claim 3, wherein polyoxyalkylene ethers of higher alcohols are used as non-ionic surfactants.

5. Pharmaceutical compositions according to claim 2 comprising lecithins as surfactants.

6. Pharmaceutical compositions according to any one of claims 1-5, wherein the gastroresistant and enterosoluble material is selected from cellulose acetophthalate, Eudragit'^R' L and S; polymethacrylic acid (38%) - polyvinylacetate (46,7%) - stearic acid (7,6%) - tetrahydrofuryl oleate (7,7%) mixture; lac gum and the like.

7. Pharmaceutical compositions according to any one of claim 2-6, wherein the antioxidant agents are selected from ascorbic acid, thiopropionic acid, 1- ascorbyl palmitate, tocopherols.

8. Pharmaceutical compositions according to any one of claims 1-7 containing from 10 to 5000 mg of GSH per unit dose.

9. Pharmaceutical compositions according to any one of claims 1-8 in form of tablets, sugar-coated tablets, hard or soft gelatine capsules, granules distributed in sachets or capsules granules in ready-to-use or extemporaneous mono- or multi-dose suspension.