Islatravir, the first of a new class of antiretrovirals, continued to demonstrate high potency and good tolerability at 96 weeks when combined with doravirine (Pifeltro), researchers reported at the virtual HIV Glasgow conference.
At week 96 after starting treatment, 90% of people treated with the selected dose of islatravir plus doravirine had undetectable HIV viral load, showing that the combination works at least as well as a standard three-drug regimen.
Islatravir (formerly known as MK-8591 or EFdA), from Merck, is a first-in-class nucleoside reverse transcriptase translocation inhibitor with multiple mechanisms of action. Besides acting as a defective building block to halt construction of new chains of DNA, it also works at a later step in the viral replication process.
Prior studies showed that islatravir has a long half-life, suggesting it may have the potential to be taken once weekly for HIV treatment or even less often for pre-exposure prophylaxis (PrEP).
Professor Jean-Michel Molina of the University of Paris presented the latest findings from a phase IIb study evaluating the safety and efficacy of islatravir plus the non-nucleoside reverse transcriptase inhibitor doravirine versus a three-drug regimen of doravirine, tenofovir disoproxil fumarate and lamivudine, the components of the Delstrigo single-tablet regimen.
HIV Glasgow 2020 Abstract 0415 (not available online)
HIV Glasgow 2020 Abstract P047 (not available online)