Daily emtricitabine/tenofovir alafenamide (F/TAF, Descovy) was non-inferior to emtricitabine/tenofovir disoproxil fumarate (F/TDF, Truvada) for pre-exposure prophylaxis (PrEP) in men who have sex with men (MSM), a researcher said here.

In what was described as the first HIV prevention trial without a placebo arm, HIV incidence rate was 0.16 per 100 person years in the F/TAF arm and 0.34 per 100 in the F/TDF arm, which met the margin of non-inferiority (IRR 0.47, 95% CI 0.19-1.15), reported Charles Hare, MD, of Kaiser Permanente San Francisco Medical Center.

The broad 95% confidence interval that spanned 1.0 meant, however, that F/TAF could not be called superior despite the two-fold difference between the point estimates.

Secondary outcomes, which were bone and renal safety, did significantly favor F/TAF over F/TDF, according to the phase III DISCOVER trial, a late-breaking presentation at the Conference on Retroviruses and Opportunistic Infections(CROI).

Speaking to MedPage Today prior to the conference, CROI vice chair Sharon Hillier, PhD, of the University of Pittsburgh, called it "the dawn of a new age in prevention studies."

At the press conference, Hillier elaborated on this, noting that this study had the fewest HIV endpoints of any modern-era prevention study. "It's a brave new world for those of us in prevention, thinking about how to actually do these studies and appropriate ways to contextualize the results," said Hillier, who moderated the press conference, but was not involved with the research.

But some members of the media threw cold water of real-world healthcare costs on this sunny new outlook, questioning the increased cost of F/TAF compared to F/TDF, especially because Truvada is due to go off patent in 2021. Read more via MedPage