Changes in renal function after switching from TDF to TAF in HIV-infected individuals: a prospective cohort study

BACKGROUND
Replacing tenofovir disoproxil fumarate (TDF) with tenofovir alafenamide (TAF) improves renal tubular markers in HIV-infected individuals, but the impact on estimated glomerular filtration rate (eGFR) remains unclear.

METHODS
We included all participants from the Swiss HIV Cohort Study who switched from a TDF to a TAF-containing antiretroviral regimen or continued TDF. We estimated changes in eGFR and urine protein-to-creatinine ratio (UPCR) after 18 months using mixed-effect models.

RESULTS
Of 3'520 participants (26.6% women, median age 50 years), 2'404 (68.5%) switched to TAF. Prior to switch, 1'664 (47.3%) had an eGFR <90 mL/min, and 1'087 (30.9%) a UPCR ≥15 mg/mmol. In patients with a baseline eGFR ≥90 mL/min, eGFR decreased with the use of TDF and TAF (-1.7 ml/min). Switching to TAF was associated with increases in eGFR of 1.5 mL/min (95% CI 0.5-2.5) if the baseline eGFR was 60-89 mL/min, and 4.1 mL/min (95% CI 1.6-6.6) if <60 mL/min. In contrast, eGFR decreased by 5.8 mL/min (95% CI 2.3-9.3) with the continued use of TDF in individuals with a baseline eGFR <60 mL/min. UPCR decreased after replacing TDF by TAF, independent of baseline eGFR.