Used in HIV prevention, dapivirine is a non-nucleoside reverse transcriptase inhibitor that works by blocking the reverse transcriptase enzyme needed for HIV replication. It is primarily formulated in a vaginal ring for long-acting, sustained release to reduce the risk of HIV-1 infection in women. The ring, designed to be replaced monthly, provides a discreet and user-controlled method for pre-exposure prophylaxis (PrEP) in regions with high HIV incidence. Dapivirine is also being studied in other delivery systems, including films and tablets, for both vaginal and rectal use, aiming to expand prevention options and improve adherence.