Islatravir Safe, Tolerable for HIV-1 PrEP in Phase 2A Trial

New 24-week findings from Merck highlight the potential of a 1-month PrEP option for low-risk patients.

New phase 2A trial data suggest once-monthly pre-exposure prophylaxis (PrEP) islatravir, an investigational nucleoside reverse transcriptase translocation inhibitor, was generally well tolerated and associated with mostly mild adverse events versus placebo in patients at low risk of contracting HIV-1 infection.

The new 24-week data, presented by Merck at the International AIDS Society (IAS) 2021 Conference on HIV Science this week, also showed islatravir levels in peripheral blood mononuclear cells (PBMCs) remained above investigators’ pre-specified efficacy pharmacokinetic threshold at both 60 mg and 120 mg doses, 8 weeks following the final trial dose.

In an interview regarding the findings at IAS 2021, study author Sharon Hillier, PhD, director of Reproductive Infectious Disease Research at UPMC Magee-Womens Hospital in Pittsburgh, discussed the implications of a tolerable and potentially efficacious one-month PrEP.

“Bottom line, pretty stellar safety profile for this drug at either concentration,” Hillier said.

Hillier also discussed ongoing phase 3 trial assessment of islatravir for HIV-1 PrEP, the benefit of these findings toward prescriber confidence, and the role of emerging preventive agents in the evolving HIV response capability.