Patent ID: 8236851

Claim:
Polymeric matrix microspherules comprising an active ingredient comprising a compound of formula I, wherein R 1 is vinyl; there is a single bond between carbon atoms 1 and 2; Ra and Rb are H, and T is —CH 2 —S—(CH 2 ) k —N(R 5 )(R 6 ) wherein k is an integer from 2 to 5; and R 5 and R 6 are each independently of the other C 1-6 alkyl; or a physiologically tolerable acid addition salt or quaternary ammonium salt thereof; wherein said microspherules have an average size of from about 1 μm to about 5000 μm, and whereby said compound of formula I, in solid or liquid form, is highly dispersed and embedded therein, wherein said polymeric matrix comprises methacrylic acid butyl ester, (2-dimethylaminoethyl)methacrylate and methyl methacrylate copolymer, and wherein the polymeric matrix microspherules stabilizes the active ingredient so that it withstands pellet preparation and provides storage-stability to the active ingredient, wherein storage-stability means that about 80% of the active ingredient remains present after storage for six months at 40° C.