Strategies of microspheres and in situ forming gel implants in long-acting and research progress in controlling burst release

Long-acting injectables(LAIs) play an important role in the field of drug preparation research because they can control drug release for a long time and decrease dosing frequency. In this review, two types of LAIs, including injectable microspheres and in situ forming gel implants, were used as the breakthrough point to analyze the strategies and technologies used in the formulation and process to achieve long-acting drug release.At the same time, in view of the common burst release phenomenon, the relevant coping strategies in the current research were summarized, which provides some reference for the design, development and optimization of such long-acting preparations.