SPOTLIGHT: Is Aspen right to abandon lenacapavir for an unproven HIV prevention pill?

Aspen Pharmacare has announced that it will not be manufacturing the lenacapavir HIV prevention injection, and that it will instead focus on producing alimatravir, an experimental HIV prevention pill.

At the start of 2020, the only medicine approved to prevent HIV infection in people who are not living with HIV in South Africa was tablets containing the antiretroviral drug tenofovir.

Apart from the tablets, ideally taken daily, HIV transmission could also be prevented by the correct use of condoms and reduced through medical male circumcision. Treating people living with HIV also helps a lot, since most people who are stable on antiretroviral treatment become non-infectious.

Since 2020, three more HIV prevention medicines have been registered in South Africa. Most prominent of these is the lenacapavir injection, which provides almost complete protection for six months at a time. The cabotegravir injection (CAB-LA) provides two months of protection and the dapivirine vaginal ring a month of partial protection. Several more products are in advanced clinical trials – including a new formulation of lenacapavir that may provide 12 months of protection and a tablet that could protect for a month.

Yet, despite the promise of new HIV prevention medicines, the rollout and uptake of these products in South Africa and globally has been slower than expected. Currently, only around 350,000 people are using HIV prevention tablets in South Africa, while in the region of 60,000 people have started taking the twice-yearly lenacapavir injections. At these levels, the number of people taking HIV prevention medicines in South Africa remains far too low to make a significant dent in the rate of new infections.

HIV prevention tablets cost the health department around $40 (roughly R700) per person per year. This price is considered to be affordable and the tablets are currently available at almost all public sector clinics in the country.

But modelling shows that long-acting injections can prevent more HIV infections than daily tablets, because their efficacy is less reliant on people taking the tablets every day. There is also evidence that many people prefer long-acting injections over daily tablets.

The cost of these newer, long-acting products has been a challenge. The health department has not procured CAB-LA injections, which was registered in the country in 2022. This was largely due to the price of around $160 per person per year. It also didn’t help that the current formulation of CAB-LA provides only two months of protection, compared with lenacapavir’s six.

In June, the health department started rolling out lenacapavir injections to about 10% of public sector facilities – for now the potential demand by far outstrips supply. The limited scale of the rollout is due to both supply and affordability challenges. The health department is paying $60 per person per year for lenacapavir through a Global Fund procurement arrangement that is allowing donors to pay an additional confidential top-up amount to Gilead Sciences above what the health department pays.