Landovitz RJ, Donnell D, Clement ME, et al. - Relative to providing daily oral tenofovir disoproxil fumarate–emtricitabine (TDF–FTC), long-acting injectable cabotegravir (CAB-LA, an integrase strand-transfer inhibitor [INSTI]) was identified as superior in preventing HIV infection among men who have sex with men (MSM) and transgender women.

• A randomized, double-blind, double-dummy, noninferiority trial.

• At-risk cisgender MSM and at-risk transgender women who have sex with men were administered CAB-LA at a dose of 600 mg, intramuscularly every 8 weeks, with daily oral TDF–FTC.

• The intention-to-treat population included 4,566 participants.

• From the United States, there were 1,698 participants, 845 of whom (49.8%) were identified as Black.

• Fifty-two participants had occurrence of incident HIV infection: 13 in the cabotegravir group (incidence, 0.41 per 100 person-years) and 39 in the TDF–FTC group (incidence, 1.22 per 100 person-years).

• 81.4% of the participants in the cabotegravir group and 31.3% of those in the TDF–FTC group reported injection-site reactions.

• Researchers identified INSTI resistance and delays in the detection of HIV infection in the participants in whom HIV infection was diagnosed following exposure to CAB-LA.