Towards the development of a longer-acting injectable contraceptive: past research and current trends

Objectives: A longer-acting injectable contraceptive that lasts for 6 months would be a valuable addition to the contraceptive method mix and ideal for women who are interested in spacing births and/or uncertain about their future reproductive plans. Here we review past applications of drug delivery technologies to injectable contraceptives as well as recent advancements in sustained drug delivery technologies that hold promise for the development of a new longer-acting injectable contraceptive product. Study design: A global landscape analysis was conducted, promising sustained drug delivery technologies, and research opportunities and partnershipswereestablishedwithexpertsinthefieldsofcontraceptionanddrugdeliverytoidentifynewapproachesindevelopingalonger-acting injectable contraceptive product. Results: The landscape analysis confirmed that a number of existing polymer systems, such as poly-lactic-co-glycolic acid and poly(epsiloncaprolactone), remain promising candidates for application to a longer-acting injectable product. Novel polymers and materials also hold promise for achieving longer release profiles and/or having other advantages over existing polymer systems, but products using these materials could potentially have longer roads to regulatory approval. Additionally, recent advancements in the manufacturing process of microspheres may benefit the development of a longer-acting injectable contraceptive.