Merck to present daily, weekly and monthly HIV data at AIDS 2026
- Week 48 primary efficacy and safety results from Phase 3 ISLEND‑1 and ISLEND‑2 will compare once‑weekly islatravir+lenacapavir (ISL/LEN) versus daily standard‑of‑care in virologically suppressed adults (Abstracts OAB1406LB, OAX1106LB).
- Week 24 primary results from Phase 2b MK‑8591B‑060 will report switch to once‑weekly islatravir+ulonivirine (ISL+ULO) versus daily BIC/FTC/TAF in virologically suppressed adults (Abstract OAB1405LB).
- Switching to doravirine/islatravir (100/0.25 mg) once‑daily maintained viral suppression at Week 96 despite baseline NNRTI resistance‑associated mutations and/or M184I/V (Abstract OAB0105LB).
- MK‑8527 (alimatravir), an investigational once‑monthly oral PrEP candidate, is in Phase 3 EXPrESSIVE‑10 and EXPrESSIVE‑11 trials and is currently enrolling in sub‑Saharan Africa and across 16 countries.
Conference overview
Merck will present new data from its HIV treatment and prevention pipeline at the 26th International AIDS Conference (AIDS 2026), held July 26–31, 2026 in Rio de Janeiro. The company highlights late‑breaker oral presentations focused on once‑weekly and once‑daily regimens and ongoing PrEP studies.
Late‑breaker and selected abstracts
Primary Week 48 efficacy and safety results from Phase 3 ISLEND‑1 and ISLEND‑2 will report on once‑weekly islatravir+lenacapavir (ISL/LEN) versus daily standard‑of‑care in virologically suppressed adults (Abstracts OAB1406LB, OAX1106LB). Week 24 primary results from the Phase 2b MK‑8591B‑060 trial will present switch data for once‑weekly islatravir+ulonivirine (ISL+ULO) versus daily BIC/FTC/TAF (Abstract OAB1405LB). An oral presentation will cover Week 96 maintenance of viral suppression after switching to doravirine/islatravir (100/0.25 mg) in the presence of baseline NNRTI resistance and/or M184I/V (Abstract OAB0105LB).
Trials, collaborations and next steps
Merck noted collaborations on these programs, including lenacapavir with Gilead and Phase 3 MK‑8527 (alimatravir) PrEP trials—EXPrESSIVE‑10 and EXPrESSIVE‑11, supported in part by the Gates Foundation—are now enrolling. Islatravir is also marketed in combination with doravirine as IDVYNSO in the U.S. and Japan.
Events and investor update
Merck will host two symposia on July 29 (policy and medical topics) open to registered attendees in‑person and virtually, and a virtual HIV Investor Event on August 3, 2026 at 08:00 a.m. ET to update on the HIV program and strategy.
Source: Merck
