During the past three decades of pharma industry, drug delivery systems has made significant advances. The sustained release pellets are used as core for the manufacture of capsule pharmaceutical dosage form, in particular for oral controlled drug release formulations. Drug delivery has now came to be recognized as a means of optimizing therapy with established drugs through better understanding of their pharmacokinetics & toxicity. By the use of new Drug Delivery systems, the bioavailability can be enhanced the therapeutic index of drugs by site specific targeting can be increased. And facilitates to reduce and excellent patient compliance can be obtained.