Lenacapavir rollout a major HIV milestone but the real test is keeping people protected

South Africa's new HIV-prevention medicine, Lenacapavir, shows great promise but the real test lies in sustaining protection for those who receive it. Clinical scientist Colleen Aldous explains that Lenacapavir, administered as injections every six months along with daily tablets, blocks a protein essential for HIV replication. It serves as an alternative to daily HIV-prevention pills, though regular testing and clinic visits remain crucial.

Initially receiving Lenacapavir marks a significant step towards HIV prevention, but the medicine's effectiveness depends on adherence to the treatment schedule and availability of clinic resources. By September 2026, over 55,000 individuals had begun the six-month regimen at 360 public facilities across six provinces. While this marks significant progress, it does not indicate how many individuals remain protected over time.

Large-scale studies, Purpose 1 and Purpose 2, demonstrated Lenacapavir's efficacy in preventing HIV. In Purpose 1, adolescent girls and young women in South Africa and Uganda, receiving lenacapavir injections every six months, experienced no HIV infections during the study period. In contrast, daily prevention tablet users had infections.

Study Purpose 2, involving men and gender-diverse individuals in seven countries, including South Africa, showed a 89% reduction in HIV infections among those receiving lenacapavir compared to 96% in the daily tablet group.

These findings bolster the case for offering Lenacapavir; however, daily prevention tablets continue to be effective when adhered to consistently. The duration of the studies, around nine to ten months, does not fully address long-term outcomes, such as rare side effects, adherence, and overall safety. Adverse events like pain, swelling, and headaches were reported but were generally mild, and reporting mechanisms like VigiAccess help monitor potential issues.

While Lenacapavir shows strong results, it is essential to maintain vigilance in testing for HIV and providing adequate care post-infection. The medicine, used both for prevention and treatment of HIV, underscores the need for comprehensive monitoring to ensure sustained protection and identify any unforeseen complications.