March 24, 2017
Two recent studies published in the Lancet HIV support guidelines that recommend tenofovir alafenamide (TAF)-based regimens for treatment for patients diagnosed with HIV-1 infection.
The researcher of the trials compared TAF, a prodrug of tenofovir, with tenofovir disoproxil fumarate (TDF), and found TAF reduces plasma concentrations of tenofovir by 90%. The researchers reported in clinical trials that TAF has demonstrated improvements in renal and bone safety—it enters cells more efficiently than TDF, and TAF can be administered to patients in lower doses. The researchers hoped to see if viral suppression could be maintained when therapy was switch from a TDF-regimen to a TAF-regimen through their trials.
The first study, by Chloe Orkin, MBChB, of Grahame Hayton Unit, Royal London Hospital, and colleagues, compared the safety and efficacy of switching to a single-tablet regimen containing Edurant (rilpivirine; Janssen), Truvada (emtricitabine; Gilead), and TAF compared with remaining on Edurant, Truvada, and TDF. The researchers analyzed 630 patients who were randomized to a TAF-based regimen (n = 316) or a TDF-based regimen (n = 314). Among both cohorts at week 48, 94% of patients maintained less than 50 copies per mL HIV-1 RNA, proving non-inferiority of TAF TDF. The researchers reported no serious adverse events among each cohort.
The second trial, by Edwin DeJesus, MD, of the Orlando Immunology Center, and colleagues, reviewed the safety and efficacy of switching to a regimen containing Edurant, Truvada, and TAF was compared to remaining on a regimen containing Sustiva (efavirenz; Bristol-Myers Squibb), Truvada, and TDF. The researchers observed 875 who were randomly assigned to a TAF-based regimen (n = 438) or a TDF-based regimen (n = 437). The researchers reported their findings at week 48 and found viral suppression was maintained in 90% of the TAF cohort, and 92% of the TDF cohort. Similar to the first study, these finding also showed non-inferiority.
Dr DeJesus and colleagues found that there were treatment-related adverse events in 13% of TAF patients and 10% in TDF patients.
“These findings support guidelines recommending tenofovir alafenamide-based regimens, including coformulation with rilpivirine and emtricitabine, as initial and ongoing treatment for HIV-1 infection,” Dr Orkin and colleagues concluded.
—Julie Gould (Mazurkiewicz)