In the open-label ISLEND-2 study, 626 participants were randomized to receive the weekly regimen or a range of daily standard-of-care therapies. The weekly regimen also demonstrated non-inferior efficacy, while viral suppression remained approximately 95%, according to Rhee. Second Weekly Program Moving Toward Phase IIIMerck also discussed islatravir plus ulonivirine, its wholly owned investigational weekly oral regimen. That portfolio includes IDVYNSO, Merck’s newly approved daily oral treatment, the two weekly treatment programs, and alimatravir. Foard said Merck estimates the HIV treatment market was about $26 billion in 2025 and could grow to roughly $32 billion by the mid-2030s.