During its 2 phase 3 clinical trials, the twice-yearly prophylaxis injection was found to be highly efficacious in preventing infection.
Yesterday, Gilead announced it had submitted its new drug application (NDA) for its therapy, lenacapavir, for pre-exposure prophylaxis (PrEP) for HIV infection. The NDA is supported from data provided from the company’s phase 3 PURPOSE 1 and PURPOSE 2 trials. The PURPOSE 1 data showed twice-yearly lenacapavir demonstrated zero infections in the lenacapavir group and 100% efficacy and superiority to background HIV incidence (bHIV) for the investigational use of HIV prevention in cisgender women.1
In the PURPOSE 2 trial there were 2 HIV infections in the lenacapavir group, demonstrating 99.9% of participants in the lenacapavir group did not acquire HIV infection and a 96% reduction in HIV infections compared to bHIV among a broad and geographically diverse range of cisgender men and gender-diverse people.1
The PURPOSE 1 trial included over 5,300 participants across South Africa and Uganda and its 100% efficacy rate surpasses the efficacy rates of current standard PrEP options like Truvada and Descovy.2
The interim analysis, conducted by an independent Data Monitoring Committee, recommended halting the blinded phase of the trial due to these compelling results. Notably, lenacapavir showed zero cases of HIV infection among recipients, contrasting with an incidence rate of 2.41 per 100 person-years in the background HIV incidence group (bHIV) and the once-daily oral Truvada group.2
The PURPOSE 2 trial included cisgender men, transgender men, transgender women, and gender non-binary individuals in Argentina, Brazil, Mexico, Peru, South Africa, Thailand and the United States who have sex with partners assigned male at birth. At interim analysis, the independent Data Monitoring Committee (DMC) confirmed that the PURPOSE 2 trial met its key efficacy endpoints of superiority of twice-yearly lenacapavir to both bHIV (primary endpoint) and once-daily oral Truvada (secondary endpoint) for PrEP. Therefore, the DMC recommended that Gilead stop the blinded phase of the trial and offer open-label lenacapavir to all participants.3
Study participants were randomized in a 2:1 ratio to lenacapavir and Truvada, respectively. Because effective PrEP options already exist, there is broad consensus in the PrEP field that a placebo group would be unethical; thus, the trial used bHIV as the primary comparator and Truvada as a secondary comparator.3
Both lenacapavir and Truvada were generally well-tolerated and no significant or new safety concerns were identified.3
Over the last few years, lenacapavir has gone through many evolutions from its FDA regulatory journey to its use as a treatment for patients with multidrug resistant HIV to potential PReP tool. To learn more about it, read The Evolution of Lenacapavir in HIV Treatment.
In its statement yesterday, Gilead said it was working to provide greater access of lenacapavir globally, especially in those areas of greatest need.