Phase 3 trial compares switch to doravirine/islatravir versus continuing bictegravir/FTC/TAF in HIV-1

This was a phase 3 randomized controlled trial involving 643 participants living with HIV-1 who were virologically suppressed on a regimen of bictegravir/emtricitabine/tenofovir alafenamide (BIC/FTC/TAF). Participants were randomized to either switch to a fixed-dose combination of doravirine 100 mg and islatravir 0.75 mg (DOR/ISL) or to continue their current BIC/FTC/TAF regimen. The primary endpoints were the percentage of participants with HIV-1 RNA ≥50 copies/mL at week 48 and the percentages with one or more adverse events (AEs) and who discontinued study intervention due to an AE up to week 48. The follow-up period was 48 weeks for the primary endpoint, with an option for a 24-week extension.

The specific numerical results for virologic efficacy, the incidence of adverse events, and discontinuation rates are not reported in the provided data. Secondary outcomes were not specified. Safety data, including serious adverse events and detailed tolerability profiles, are also not reported. The trial's primary safety outcomes were defined but their results are pending.

A key limitation is the absence of reported efficacy and safety results, which prevents any assessment of non-inferiority or comparative safety between the two regimens. The study setting was not reported. The trial was sponsored by Merck Sharp & Dohme LLC.

In terms of practice relevance, the full clinical implications of switching from a guideline-recommended integrase inhibitor-based regimen (BIC/FTC/TAF) to this novel two-drug combination (DOR/ISL) cannot be determined until the complete efficacy and safety data are published. Clinicians should await peer-reviewed publication of the final results, including detailed safety analyses and longer-term data from the extension phase, before considering any changes to clinical practice based on this trial.