Bictegravir/Emtricitabine/Tenofovir Alafenamide in Virologically Suppressed People with HIV Aged ≥ 65 Years: Week 48 Results of a Phase 3b, Open-Label Trial

Introduction We report the 48-week results of an ongoing study to assess the efficacy and safety of switching older people with HIV to bictegravir/emtricitabine/tenofovir alafenamide (B/F/TAF). Methods This was a 96-week, phase 3b, open-label, single-arm study (GS-US-380-4449; NCT03405935). Virologically suppressed individuals aged >= 65 years receiving elvitegravir/cobicistat/emtricitabine/tenofovir alafenamide or a tenofovir disoproxil fumarate-based regimen were switched to B/F/TAF. Primary endpoint was the percentage of participants with HIV-1 RNA < 50 copies/ml at week 24. Results Eighty-six participants (median age 69 [range 65-80] years; 87% male; 95% white) were enrolled and treated in five European countries. Rates of virologic suppression were 97.7% at week 24 and 90.7% at week 48; none had HIV-1 RNA >= 50 copies/ml, and 100% had virologic suppression by missing = excluded analysis at both time points. No treatment-emergent resistance was observed. There were no grade 3-4 study drug-related adverse events (AEs) or study drug-related serious AEs or deaths. Three AEs led to premature discontinuation; one (moderate abdominal discomfort) was attributed to the study drug by the investigator. At week 48, median changes from baseline in weight and estimated glomerular filtration rate were + 0.1 kg (interquartile range [IQR] - 1.0, 2.3) and - 6.0 ml/min (IQR - 10.2, 0.0), respectively. There were no clinically relevant changes from baseline to week 48 in fasting lipid parameters. Treatment satisfaction improved, and health-related quality of life was maintained from baseline through week 48. Median adherence to the study drug was 98.6% (IQR 96.0, 100). Conclusions Switching to B/F/TAF was effective and well tolerated through 48 weeks in virologically suppressed adults aged >= 65 years.