Second, it’s expensive. CAB-LA is priced at over $22,000 per person per year in the US. It could be covered to some extent by health insurance companies, but not everyone has health insurance.

The drug manufacturer will lower the price for the markets in low- and middle-income countries, but the exact cost is not yet known. Some estimates are around $250 per person per year. That’s still about five times as much as oral PrEP costs. The increased effectiveness may be worth it for people at high risk of getting HIV, but getting it to those people will be challenging for ministries of health.

Third, logistical issues complicate delivery of injectable PrEP, including the need for refrigerators to store the drug and nurses to give the injections. Clinics may not be set up to provide many injections in a given day, and limited availability may mean people can’t get the shots when they need them.

Finally, continuing to get injections over time is still likely to be a problem. The experience with injectable contraception has taught us that up to half of people who select that form of family planning stop it within a year. Injectable PrEP does not solve the other barriers people face, like transport to clinic and prioritisation of HIV prevention.

The lack of access raises important ethical concerns. Most of the thousands of people in the CAB-LA trials live in countries without access to it, including Botswana, Eswatini, Kenya, Malawi, South Africa, Uganda, and Zimbabwe among others. Processes to enable access are unacceptably slow, although the drug is available in the US (and just recently Zimbabwe).

Where to go from here?

Despite these challenges, injectable PrEP is a huge advantage for the HIV prevention toolbox. Choice is critical for most interventions to work, and HIV prevention is no different. PrEP use increases when people are given effective options and can choose what works best for them.

PrEP needs to be easier for people to take, for instance by making it more convenient and less medical. Programmes are starting to do this through community delivery. That approach may be more challenging with injections, but it may get easier with time and with injections in the skin, like lenacapavir. Advocacy will be critical for expediting the regulatory process and negotiating with pharmaceutical companies to license other companies to produce more affordable generics. (The Conversation)

*Jessica Haberer, Director of Research, Massachusetts General Hospital Centre for Global Health and Professor of Medicine, Harvard Medical School, Harvard University