The future of HIV prevention is here. Injectable cabotegravir (CAB) is the most effective, longest-acting option for avoiding the virus. Until now, pre-exposure prophylaxis (or PrEP) medicine taken to prevent HIV has only been available as an oral pill that must be taken daily. CAB needs to be injected only once every two months.
Our organizations, FHI 360 and Pangaea Zimbabwe AIDS Trust (PZAT), are working together with a consortium of partners under the MOSAIC project to support the market introduction of injectable CAB for PrEP and other new prevention products. Two clinical trials conducted by the HIV Prevention Trials Network (HPTN-083 and HPTN-084) found injectable CAB to be safe and highly efficacious — more effective than daily oral PrEP in reducing HIV in populations who are at high risk. Following the trials, in December 2021, the U.S. Food and Drug Administration (FDA) approved the medication for use in the United States. The World Health Organization (WHO) is expected to release global guidance on injectable CAB for PrEP soon.
The power of choice
This prevention product is a major milestone in the fight against HIV and will give people more choice in how they protect their health. The introduction of CAB for PrEP expands the range of methods for HIV prevention, similar to the multiple methods available for contraception. People will be able to choose which option best meets their needs and can change their choice over time.
Injectable CAB is an empowering option for anyone who may have avoided taking preventative measures for fear of disrupting trust in their relationships. We see this in our work in Africa, where some women feel pressured to choose between protecting their relationship or preventing HIV. Now, they will be able to get their preventative shot and not have to disclose that choice if they prefer not to.
Going from research to rollout
We know that CAB for PrEP is an option that can transform HIV prevention, but there are still many things to learn and take into consideration as we move this product from research to rollout.
In the U.S., the FDA requires people to take a viral load test before starting CAB injections to make sure they do not already have HIV. This is because the standard rapid tests do not show a positive result right away, and CAB is so suppressive once started that acute HIV could go undetected for weeks or months. But viral load tests are expensive and in short supply. In many African countries, these tests are used to see if treatment is working, so using tests for prevention would mean taking away from the already limited supply of tests available for treatment.
Then there is the issue of the drug “tail.” CAB stays in the body a long time — at least a year. Without repeat injections every two months, the medication will become less effective over time. People will need to protect themselves with another shot or another form of prevention. If they are exposed to HIV with a low level of CAB in their body, they may be more likely to develop a drug-resistant strain of the virus. This is a challenge for health providers and community organizations to navigate as we learn how people use CAB. Will people come back for their CAB injections every two months until they are no longer exposed to HIV, or will they cycle off CAB injections, as we see with contraception use? If they cycle off and continue to be exposed to HIV, will we see increasing rates of drug-resistant HIV, and if so, will that threaten treatment?
FHI 360, PZAT and our MOSAIC partners are activating our global and local communities of program implementers, managers, policymakers and others to be prepared to respond as soon as shots can be administered. To get there, we need more real-world evidence. This time next year, MOSAIC will be delivering CAB for PrEP in Zimbabwe, Kenya, Uganda, Lesotho and South Africa through an implementation research study called CATALYST. It is likely this will be the first time CAB is made available in Africa outside of clinical trials. We are eager to introduce this game-changing product and see it lead to lower HIV incidence.
We need widespread prevention methods available to everyone to control the HIV epidemic — treatment alone will not suffice. And to help normalize and destigmatize prevention, making it something everyone does and takes responsibility for, we must have more readily available options for people to choose from. Injectable CAB for PrEP is our next and best shot.