Bictegravir/emtricitabine/tenofovir alafenamide in people with HIV aged ≥50: low discontinuation rates and favorable metabolic outcomes over 36 months

Purpose: Real-world evidence on the long-term safety and efficacy of switching to bictegravir/emtricitabine/ tenofovir alafenamide (B/F/TAF) in this population remains limited. We evaluated virological, immunological, and metabolic outcomes of B/F/TAF in aging PWH with sustained virological suppression. Method: We conducted a multicenter retrospective cohort study within the SHiNe-SHiC network, including 188 PWH aged ≥50 years who switched to B/F/TAF. Data from four centers in Sardinia and Sicily were analyzed. Demographic, clinical, viro-immunological, and biochemical data were collected at baseline, 12, 24, and 36 months. Rates of treatment discontinuation (TD) were assessed using survival analysis. Results: Among 188 participants (median age 58 years [IQR 54–63]; 18.6% >65 years), 69.1% were cisgender men. Comorbidities were frequent: dyslipidemia (59.0%), hypertension (44.1%), and psychiatric disorders (14.9%). A total of 22.3% used ≥5 non-ART medications (Table 1). During 8726 person-months of follow-up, 11 treatment discontinuations occurred (rate: 1.26/1000 personmonths; 95% CI: 0.70–2.28). The cumulative probability of discontinuation was 2.66% at 12 months (95% CI: 1.12– 6.28) and 5.14% at 36 months (Figure 1). Discontinuation causes included adverse events (n=4), person decision (n=3), simplification (n=3), and one virological failure. Virological suppression was maintained in 92.5% of participants at 36 months (Figure 2) and CD4 count did not significantly change. Lipid parameters showed significant reductions: total cholesterol (p=0.0003), LDL (p=0.0158), and triglycerides (p=0.0255). Total cholesterol/HDL ratio improved significantly at all timepoints (p=0.0214). No clinically significant changes were observed in creatinine, AST, ALT, or HDL levels (Table 2). Conclusions: Switching to B/F/TAF in virologically suppressed PWH aged ≥50 years was associated with sustained virological control, stable immunological parameters, and favorable metabolic outcomes, including improvements in lipid profiles. The low discontinuation and virological failure rates support the use of B/F/TAF as an effective and safe strategy in aging PWH, including those with polypharmacy and comorbidities.