Renal Function of Participants in the Bangkok Tenofovir Study-Thailand, 2005-2012

Background. Tenofovir disoproxil fumarate (tenofovir) has been associated with renal dysfunction in people infected with human immunodeficiency virus (HIV) receiving combination antiretroviral therapy. We reviewed data from an HIV preexposure prophylaxis trial to determine if tenofovir use was associated with changes in renal function in an HIV-uninfected population. Methods. During the trial, 2413 HIV-uninfected people who inject drugs were randomized to receive tenofovir or placebo. We assessed the renal function of trial participants with the Cockcroft-Gault, Modification of Diet in Renal Disease (MDRD), and Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equations using t tests for cross-sectional analysis and linear regression for longitudinal analysis. Results. Creatinine clearance and glomerular filtration rate (GFR) results were lower at 24, 36, 48, and 60 months in the tenofovir group compared with the placebo group. Results declined more in the tenofovir group than in the placebo group during follow-up using the Cockcroft-Gault (P < .001) and CKD-EPI (P = .007) equations, but not MDRD (P = .12). Creatinine clearance measured when study drug was stopped was lower in the tenofovir group than the placebo group (P < .001), but the difference resolved when tested a median of 20 months later (P = .12). Conclusions. We found small but significant decreases in cross-sectional measures of creatinine clearance and GFR in the tenofovir group compared with the placebo group and modest differences in downward trends in longitudinal analysis using the Cockcroft-Gault and CKD-EPI equations. These results suggest that with baseline assessments of renal function and routine monitoring of creatinine clearance during follow-up, tenofovir can be used safely for HIV preexposure prophylaxis.