Cabotegravir is an investigational drug that is being studied for the treatment and prevention of HIV infection. Cabotegravir belongs to a class (group) of HIV drugs called integrase inhibitors. Integrase inhibitors block an HIV enzyme called integrase. (An enzyme is a protein that starts or increases the speed of a chemical reaction.) By blocking integrase, integrase inhibitors prevent HIV from multiplying and can reduce the amount of HIV in the body. Cabotegravir does not require boosting with an additional drug. Two forms of cabotegravir are being studied: tablets that are taken by mouth (known as oral cabotegravir or oral CAB) and a long-acting injectable form that is injected into the muscle (known as cabotegravir LA or CAB LA; LA stands for "long-acting"). (A long-acting drug formulation works over a long period of time. Using this type of drug might mean that the drug could be taken less often, making a treatment or prevention regimen simpler to take.) Cabotegravir is in Phase-III clinical trials for HIV infections.