On December 20, 2021, the US Food and Drug Administration (FDA) approved long-acting cabotegravir, the first injectable medication to prevent HIV. Two randomized clinical trials that together included 7790 study participants demonstrated that long-acting cabotegravir was more likely to prevent HIV acquisition than daily oral medication for people at risk of sexually acquiring HIV, including men who have sex with men, heterosexual women, and transwomen.1 The advantage of the medication was attributed partly to the high efficacy of this and other integrase inhibitors and, in part, to better adherence for an injection compared with a once-daily pill regimen; whether this advantage remains outside of clinical trials remains unknown. It is hoped that this new tool for HIV prevention will accelerate progress toward the US goal of reducing new infections by 90% by 2030. However, the potential for public health benefit is jeopardized by the cost and complexity of the US health care system.