Claims
- 1. A solid pharmaceutical composition for release of a biologically active substance into a desired aqueous environment, containing a core and an outer layer coated thereon,
- said core consisting essentially of between 17 and 93% by weight of the biologically active substance, between 0.01 and 7% by weight of a water swellable polymer material and between 0 and 83% of one or more accessory ingredients, relative to the total weight of the core; and
- the outer layer consisting essentially of between 25 and 75% by weight of the biologically active substance, between 25 and 75% by weight of a material for enabling rapid dispersion of the outer layer into the aqueous environment and 0 to 50% by weight of one or more accessory ingredients, relative to the total weight of the outer layer.
- 2. A pharmaceutical composition according to claim 1, in unit dose form.
- 3. A pharmaceutical composition according to claim 1 for oral administration.
- 4. A pharmaceutical composition according to claim 1 for veterinary use.
- 5. A pharmaceutical composition according to claim 4 adapted for oral administration to the rumen of an animal.
- 6. A pharmaceutical composition according to claim 5 which is an intra-rumenal bolus provided with a means to inhibit regurgitation.
- 7. A pharmaceutical composition according to claim 1 wherein the material for enabling rapid dispersion of the outer layer is a water-swellable polymer.
- 8. A pharmaceutical composition according to claim 1 wherein the core contains between 0.01 and 2.0% by weight of a water swellable polymer.
- 9. A pharmaceutical composition according to claim 1 wherein the biologically active substance is an antibacterial or anthelmintic agent.
- 10. A pharmaceutical composition according to claim 9 wherein the antibacterial agent comprises a sulphonamide or a salt thereof and/or a 2,4-diaminopyrimidine or a salt thereof.
- 11. A pharmaceutical composition according to claim 9 wherein the antibacterial agent comprises 2,4-diamino-5-(8-dimethylamino-7-methyl-5-quinolymethyl)pyrimidine or a salt thereof together with sulphadimidine or a salt thereof.
- 12. A pharmaceutical composition according to claim 11 wherein the core contains from 1 to 5% of the pyrimidine and from 16 to 80% of the sulphonamide and the coating contains from 10 to 20% of the pyrimidine and 30 to 40% of the sulphonamide.
- 13. A pharmaceutical composition according to claim 12 which provides a dose of 2,4-diamino-5-(8-dimethylamino-7-methyl-5-quinolylmethyl)pyrimidine in the range 1 to 24 mg/kg and a dose of sulphadimidine in the range 9 to 216 mg/kg.
- 14. A method of treating a bacterial or helminthic infection which comprises administering to an animal in need thereof, a composition as defined in claim 1.
Priority Claims (1)
Number |
Date |
Country |
Kind |
8915716 |
Jul 1989 |
GBX |
|
Parent Case Info
This is a continuation of application Ser. No. 07/548,712, filed Jul. 6, 1990, now abandoned.
US Referenced Citations (7)
Foreign Referenced Citations (5)
Number |
Date |
Country |
838506 |
Feb 1976 |
BEX |
0236002 |
Feb 1987 |
EPX |
0238207 |
Sep 1987 |
EPX |
1330829 |
Sep 1973 |
GBX |
1499672 |
Feb 1978 |
GBX |
Continuations (1)
|
Number |
Date |
Country |
Parent |
548712 |
Jul 1990 |
|