Long-Acting Cabotegravir Protects Macaques Against Repeated Penile Simian-Human Immunodeficiency Virus Exposures

We used a novel penile simian-human immunodeficiency virus (SHIV) transmission model to investigate whether long-acting cabotegravir (CAB LA) prevents penile SHIV acquisition in macaques. Twenty-two macaques were exposed to SHIV via the foreskin and urethra once weekly for 12 weeks. Of these, 6 received human-equivalent doses of CAB LA, 6 received oral emtricitabine/tenofovir disoproxil fumarate, and 10 were untreated. The efficacy of CAB LA was high (94.4%; 95% confidence interval, 58.2%-99.3%) and similar to that seen with oral emtricitabine/tenofovir disoproxil fumarate (94.0%; 55.1%-99.2%). The high efficacy of CAB LA in the penile transmission model supports extending the clinical advancement of CAB LA preexposure prophylaxis to heterosexual men.