THURSDAY, Aug. 12, 2021 (HealthDay News) -- For men who have sex with men (MSM) and transgender women, long-acting injectable cabotegravir (CAB-LA, an integrase strand-transfer inhibitor [INSTI]) is superior to tenofovir disoproxil fumarate-emtricitabine (TDF-FTC) for preventing HIV infection, according to a study published in the Aug. 12 issue of the New England Journal of Medicine.
Raphael J. Landovitz, M.D., from the David Geffen School of Medicine at the University of California in Los Angeles, and colleagues conducted a randomized, double-blind, double-dummy, noninferiority trial to compare CAB-LA to daily oral TDF-FTC for the prevention of HIV infection. A total of 4,566 at-risk cisgender MSM and at-risk transgender women who have sex with men were included as the intention-to-treat population.
On review of the results from the first preplanned interim end point analysis, the trial was stopped early for efficacy. The researchers found that incident HIV infection occurred in 52 participants: 13 and 39 in the CAB-LA and TDF-FTC groups, respectively (incidence, 0.41 and 1.22 per 100 person-years, respectively; hazard ratio, 0.34). Across prespecified subgroups, the effect was consistent. Injection-site reactions were reported in 81.4 and 31.3 percent of those in the CAB-LA and TDF-FTC groups, respectively. INSTI resistance and delays in the detection of HIV infection were noted in participants in whom HIV was diagnosed after exposure to CAB-LA.
"The logistics involved in implementation of the use of CAB-LA for preexposure prophylaxis will require new consideration," the authors write. "CAB-LA is an effective strategy for the prevention of HIV infection that will expand preexposure prophylaxis options."
ViiV Healthcare and Gilead Sciences donated trial medications and matching placebos, and ViiV Healthcare provided additional funding.