Efficacy and Safety of Tenofovir Alafenamide vs. Tenofovir Disoproxil Fumarate in HIV-infected, Virologically Suppressed Black and Non-Blacks Adults Through Week 96: Subgroup Analysis of a Randomized Switch Study

Abstract

Objective: Black adults are disproportionately affected by HIV and kidney disease. The objectives of this study were to assess the efficacy and safety in Black and non‐Black subjects switching emtricitabine/disoproxil fumarate (FTC/TDF) to emtricitabine/ tenofovir alafenamide (FTC/TAF) versus maintaining FTC/TDF in human immunodeficiency virus type 1 (HIV‐1) infected subjects who are virologically‐suppressed on regimens containing FTC/TDF, as determined by the proportion of subjects with HIV‐1 RNA < 50 copies/mL. Methods: We conducted a 96‐week subgroup analysis by race (Black vs. non‐Black) for efficacy (pre‐specified) and safety (post‐hoc) from a randomized, double blind, active‐controlled study in virologically suppressed HIV‐infected individuals who switched to emtricitabine/tenofovir alafenamide (FTC/TAF) from FTC/tenofovir disoproxil fumarate (FTC/TDF) vs continuing FTC/TDF while remaining on the same third agent. Results: Of the 663 treated, 136 (20.5%) self‐identified as Black (FTC /TAF n=69, FTC /TDF n=67). Baseline viral load, CD4 counts, renal laboratory parameters, and bone mineral density (BMD) were similar between the two arms within Blacks and non‐Blacks. For Blacks, virologic success by FDA snapshot algorithm at week 96 was FTC /TAF 87.0% vs. FTC /TDF 88.1%; for non‐Blacks, it was 89.0% vs 89.7%. Few participants discontinued study drug due to adverse events in either subgroups (Black, FTC /TAF 0 vs. FTC /TDF 1.5%; non‐Black, 3.0% vs. 1.1%). In assessment of renal and bone safety using estimated glomerular filtration rate (eGFR), renal biomarkers, and BMD, there were differences between two arms that generally favored FTC/TAF over FTC/TDF. In the overall population, no cases of Fanconi syndrome or proximal renal tubulopathy occurred with FTC/TAF; one FTC/TDF participant discontinued study drug due to proximal tubulopathy. Conclusion: In virologically‐suppressed black adults, FTC/TAF demonstrated improvements in renal and bone safety over FTC/TDF with similar sustained efficacy at week 96. These results support switching to FTC/TAF from FTC/TDF for the treatment of HIV‐1 infection in black adults.