Injectable medicinal compositions

Claim 1

A biodegradable injection or implantation carrier readily hydrolized by body fluids and thereby gradually releasing a steroid on administration of the compound, comprising a steroid compound entrapped within at least about an equal weight of a polymeric matrix composed of a cross-linked copolymer of stoichiometric amounts of each of a compound containing two or more groups selected from the group glycerol, sorbitol, erythritol, inositol, glycols based on polyethylene oxide, 4,4'-dihydroxyphenyl-2,2-propane, 1,2--dihydroxybenzene, 1,3-dihydroxy-benzene, 1,4-dihydroxy-benzene, 1,2,3-trihydroxy-benzene, 1,2,4-trihydroxy-benzene, 1,3,5--trihydroxy-benzene, lactic acid, malic acid, 2-hydroxy-isobutyric acid, 10-hydroxydecanoic acid, 12-hydroxyoctadecanoic acid, 12-hydroxy(cis)-9-octadecenoic acid, 2-hydroxycyclo-hexanecarboxylic acid (hexahydrosalicyclic acid), 2-hydroxy-2--phenyl-(D)-propionic acid, diphenylhydroxyacetic acid, ascorbic acid, citric acid, tartaric acid, 2-hydroxy-3-methyl-(D)--succinic acid, 2-hydroxybenzoic acid, 3-hydroxybenzoic acid, 4-hydroxybenzoic acid, 2,3-dihydroxybenzoic acid, 2,4-dihydroxybenzoic acid, 2,5-dihydroxybenzoic acid, 2,6-dihydroxybenzoic acid, 2,3,4-trihydroxybenzoic acid, 2,4,5-trihydroxybenzoic acid, 2,4,6-trihydroxybenzoic acid, 3,4,5-trihydroxybenzoic acid, oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, 1,2-cyclohexanedicarboxylic acid, 1,3-cyclohexane-dicarboxylic acid, 1,4-cyclohexanedicarboxylic acid, phthalic acid, isophthalic acid, teraphthalic acid, and mixtures thereof, consisting of --OH and --COOH groups and a bisdihydropyran of general formula I. ##STR9## wherein R is an organic bridging group which is unreactive to the --OH or --COOH groups selected from the group consisting of: ##STR10##