Weekly HIV Therapy Meets Primary Endpoint

Patients who switched from daily antiretroviral therapy maintained virologic suppression in two phase 3 trials.

By
Kathryn Wighton
July 23, 2026
3 min

MDSpire News

Objective:

To evaluate the efficacy and safety of a once-weekly oral regimen combining islatravir and lenacapavir compared to daily antiretroviral therapy in adults with virologically suppressed HIV.

Approach:

Trial Design: The phase 3 ISLEND-1 and ISLEND-2 trials assessed a once-weekly single-tablet regimen containing islatravir 2 mg and lenacapavir 300 mg in adults with virologically suppressed HIV.
ISLEND-1: Compared patients switching from bictegravir/emtricitabine/tenofovir alafenamide to the investigational regimen with those continuing their existing treatment.
ISLEND-2: Included patients on other daily oral standard-of-care regimens and followed a similar design to ISLEND-1.

Key Findings:

In ISLEND-1, treatment-related adverse events occurred in 13.5% of patients receiving islatravir/lenacapavir and 13.2% in the comparator group.
In ISLEND-2, treatment-related adverse events occurred in 18% of patients receiving islatravir/lenacapavir and in fewer than 1% of those receiving standard-of-care therapy.

Interpretation:

Limitations:

The islatravir/lenacapavir combination remains investigational and has not been approved for clinical use.
The trials did not report long-term outcomes beyond 48 weeks.