Long acting HIV therapies are designed to maintain effective concentrations of antiretroviral medicines in the body for extended periods, reducing the need for daily oral dosing in certain circumstances. Cabotegravir is an integrase strand transfer inhibitor that has been developed in a long acting injectable formulation. For HIV prevention, long acting injectable cabotegravir is known as CAB LA and is used as pre exposure prophylaxis or PrEP for people who are HIV negative and at substantial risk of acquiring HIV. The World Health Organization recommends CAB LA as an additional HIV prevention choice within comprehensive prevention approaches.
CAB LA is administered by intramuscular injection rather than being taken as a daily tablet. WHO guidance describes an initial injection schedule followed by injections at eight week intervals. HIV testing is an important part of the process because antiretroviral medicines used as PrEP are intended for people who do not have HIV infection. Current WHO guidance also emphasizes HIV testing when providing long acting injectable PrEP.
Key aspects of long acting cabotegravir include:
Major clinical research has evaluated CAB LA in different populations. HPTN 083 studied cisgender men who have sex with men and transgender women who have sex with men, while HPTN 084 evaluated cisgender women in several countries in sub Saharan Africa. WHO reported that these randomized controlled trials found CAB LA to be highly effective in preventing HIV acquisition compared with daily oral tenofovir disoproxil fumarate and emtricitabine.
The HPTN 084 study enrolled 3,223 women aged 18 to 45 years across 20 sites in seven countries. During the study, four participants receiving long acting cabotegravir acquired HIV compared with 34 participants receiving daily oral FTC/TDF. The reported analysis found an 89 percent reduction in HIV acquisition with CAB LA compared with daily oral FTC/TDF. Both approaches were generally well tolerated, although injection site reactions occurred more frequently in the cabotegravir group.
These studies contributed to WHO guidance recommending long acting injectable cabotegravir as an additional prevention option. However, WHO also identifies areas requiring continued research, including HIV drug resistance, testing procedures, service delivery, resource requirements, and use in populations or settings not represented in the original trials.
Long acting cabotegravir is different from long acting treatment approaches for people already living with HIV, so the intended use of a particular formulation should be confirmed with a qualified healthcare professional. HIV prevention medicines do not replace testing, and people with possible HIV exposure should receive appropriate medical guidance about testing and prevention options.