Drug delivery system
First Claim
1. A controlled release formulation comprising an adsorbate of a mixture of 1 part by weight of a pharmaceutically useful active ingredient in substantially amorphous form and from 0.1 to 10 parts by weight of an inactive substance adsorbed on a cross-linked polymer in a ratio of 1 part by weight of said mixture to 0.5-20 parts by weight of cross-linked polymer, said inactive substance being selected to modify the dissolution of the active drug from the cross-linked polymer in vivo, wherein the inactive substance is a substance whose solubility in aqueous media is inversely proportional to that of the active ingredient, with the proviso that the active ingredient is not a dihydropyridine when the inactive substance is polyvinylpyrrolidone with an average molecular weight in the range 15,000 to 50,000 and the cross-linked polymer is cross-linked polyvinylpyrrolidone.
1 Assignment
0 Petitions
Accused Products
Abstract
A controlled release formulation comprising an adsorbate of a mixture of a pharmaceutically useful active ingredient and an inactive substance adsorbed on a cross-linked polymer. The inactive substance is selected to modify the dissolution of the active ingredient from the cross-linked polymer in vivo.
-
Citations
12 Claims
- 1. A controlled release formulation comprising an adsorbate of a mixture of 1 part by weight of a pharmaceutically useful active ingredient in substantially amorphous form and from 0.1 to 10 parts by weight of an inactive substance adsorbed on a cross-linked polymer in a ratio of 1 part by weight of said mixture to 0.5-20 parts by weight of cross-linked polymer, said inactive substance being selected to modify the dissolution of the active drug from the cross-linked polymer in vivo, wherein the inactive substance is a substance whose solubility in aqueous media is inversely proportional to that of the active ingredient, with the proviso that the active ingredient is not a dihydropyridine when the inactive substance is polyvinylpyrrolidone with an average molecular weight in the range 15,000 to 50,000 and the cross-linked polymer is cross-linked polyvinylpyrrolidone.
Specification