Injections of cabotegravir administered every two months prevent HIV at least as well as daily Truvada (tenofovir disoproxil fumarate/emtricitabine). Study HPTN 083, launched in 2016, enrolled 4,570 men and transgender women who have sex with men. They were randomized to receive either long-acting injections of the experimental integrase inhibitor every eight weeks plus daily placebo pills or placebo injections plus daily Truvada pills. Of the 50 people who acquired HIV, 12 were taking cabotegravir and 38 were taking Truvada. The HIV incidence rate was 0.38% in the cabotegravir group versus 1.21% in the Truvada group, showing that the injections were 69% more effective. Although Truvada works very well if taken consistently, the researchers suggest cabotegravir’s advantage is likely due to better adherence. Because of trial disruptions related to COVID-19, the study was stopped early, and all participants were offered cabotegravir. A companion trial of long-acting cabotegravir for women is currently underway in Africa.
Prevention: Long-Acting PrEP
The injectable cabotegravir, given every eight weeks, is just as effective as daily Truvada for HIV prevention.