Phospholipid-coated microcrystals for the sustained release of pharmacologically active compounds and methods of their manufacture and use

Abstract

The present invention relates to pharmaceutical compositions for the sustained release of pharmacologically active compounds and methods of their manufacture and use. Sustained release times of 10-12 days have been achieved with the present invention. The present invention provides microcrystal compositions. The microcrystals comprise pharmacologically active compounds and are contained within a phospholipid layer which contains a unique combination of phospholipids. The present invention may be applied to a wide range of pharmaceutical compositions which may be rendered suitable for injection. The microcrystals are of varying sizes. At least 50 percent of the microcrystals are from 0.5 &mgr;m to about 3.0 &mgr;m in diameter, at least ten percent of the microcrystals are from about 3.0 &mgr;m to about 10 &mgr;m in diameter, and the composition contains microcrystals which are greater than 10 &mgr;m in diameter. In preferred embodiments, at least about 1% of the microcrystals are greater than 10 &mgr;m in diameter. The compositions and methods are useful for treating respiratory diseases, infections, inflammation, and pain in a variety of mammals. The compounds and methods are also able to sharply reduce the toxicity of drug compounds.