Gastroretentive drug-delivery systems have the potential to prolong the gastric retention time and provide controlled/sustained release of a drug at the absorption site, thereby improving the bioavailability. Advantageous features include reduction in dose, side effects and dosing frequency. Research inputs have led to exploration of novel gastroretentive systems. The present review explores various patents issued on gastroretentive drug delivery on the basis of the therapeutic category of drugs. It traces US, EP and WIPO patents issued in the last 10 years. Various patents have revealed that gastrocarriers can effectively enhance therapeutic activity of a drug. Drugs acting on the CNS have been prominently investigated, followed by antimicrobials and locally acting drugs. Areas of future research can be drugs acting on the cardiovascular system.
Keywords: EP and WIPO patents; US; bioavailability; gastrorentive carrier systems (GRCS); in vitro release; patents; plasma concentration; polymers; therapeutic effect.