Switching PLWH with multidrug-resistant HIV to B/F/TAF plus doravirine is effective, well tolerated through 48 weeks

A small study, funded by two pharmaceutical companies, found a regimen consisting of bictegravir/emtricitabine/tenofovir alafenamide (B/F/TAF) as well as doravirine was well tolerated and efficacious in heavily treatment-experienced people living with HIV (PLWH). An even smaller substudy found no concerning pharmacokinetic interactions between these two drugs.

About This Study

“Bictegravir/Emtricitabine/Tenofovir Alafenamide Plus Doravirine in Highly Treatment-Experienced Men With Multidrug-Resistant HIV” was published online on March 6, 2023, in AIDS. The lead author is Felicia L. Sterman, M.D., of Gilead Sciences, Inc., in Foster City, Calif. Another study author is from Merck & Co. The two pharmaceutical companies manufacture bictegravir and doravirine, respectively. [Editor’s note: Both companies are current or past advertisers on TheBodyPro. All decisions regarding what studies to cover in the This Week in HIV Research series are made exclusively by our editorial team, and are based on our independent assessment of the study’s clinical relevance.]

Key Research Findings

This trial among 20 patients of a private medical practice evaluated the tolerability and efficacy of switching highly treatment-experienced PLWH with extensive drug resistance from rilpivirine/emtricitabine/tenofovir alafenamide plus dolutegravir to B/F/TAF plus doravirine. All participants were assigned male at birth (median age 65 years, 95% white) and had been virally suppressed on their prior regimen.

Forty-eight weeks after switching, all participants were virally suppressed, their body mass index (a potential concern when individuals begin taking an integrase inhibitor) had not changed, and no treatment-related adverse events were reported. At week 4, three of 16 participants were viremic. However, all subsequently achieved viral suppression.

Among a subset of 10 participants, pharmacokinetic parameters for bictegravir and doravirine were similar to previously published literature that considered each drug separately, and no drug-drug interactions between these two compounds were observed.

Quality-of-life questionnaires at baseline and study end found no difference in work productivity or sleep quality.

Discussion Highlights and Implications for Practice

The researchers pointed out that study was conducted during 2020-2021, partly coinciding with COVID-19-related lockdowns, which may have affected quality-of-life parameters. In addition, study limitations included the small sample size, its relative racial and ethnic homogeneity, and the lack of women participants. This was a single-site study at a private medical practice whose patient population may differ from that at a large clinic or in the general population, the study authors cautioned. In addition, while HIV resistance mutations were assessed, clade information was not available for all participants.

The authors stated that it can be a challenge to switch antiretroviral therapy regimens in older PLWH who have been on treatment for a long time and may have comorbidities. They emphasized the importance of choosing regimens that are compatible with common comedications, such as proton pump inhibitors or H2 blockers, and may help pre-empt drug-drug interactions. The B/F/TAF plus doravirine regimen is one such option, they concluded.

By Barbara Jungwirth