Gilead Sciences and Merck announced that the phase 3 ISLEND-1 and ISLEND-2 trials met their primary efficacy endpoints at week 48 for an investigational once-weekly oral regimen combining islatravir and lenacapavir in patients with virologically suppressed HIV.
According to a joint company press release, the primary endpoint in both studies was the proportion of participants with HIV-1 RNA levels of at least 50 copies/mL at week 48, as assessed by the US Food and Drug Administration snapshot algorithm.
In the randomized, double-blind ISLEND-1 trial, participants receiving bictegravir/emtricitabine/tenofovir alafenamide either switched to once-weekly islatravir/lenacapavir or continued bictegravir/emtricitabine/tenofovir alafenamide. The companies reported that the investigational regimen was statistically noninferior to bictegravir/emtricitabine/tenofovir alafenamide at week 48 of primary analysis.
In the open-label ISLEND-2 trial, participants receiving stable daily antiretroviral therapy either switched to once-weekly islatravir/lenacapavir or remained on their current regimen. The companies reported that the investigational regimen was statistically noninferior to standard-of-care daily oral antiretroviral therapy.
Gilead and Merck also reported that the safety profile of islatravir/lenacapavir was generally comparable to the comparator regimens in both studies and that no new safety concerns were identified.
Islatravir is a next-generation nucleoside analog that inhibits HIV-1 replication through multiple mechanisms. Lenacapavir is a capsid inhibitor designed to act at multiple stages of the HIV life cycle. The companies stated that the potency and pharmacokinetic properties support once-weekly oral dosing, if approved.
Gilead and Merck said they plan to submit the phase 3 findings for presentation at a future scientific congress and to file the data with regulatory authorities globally.
Islatravir and lenacapavir in combination remain investigational and are not approved for use.
Source: Gilead and Merck
