2259. Effect of Discontinuation of Tenofovir Disoproxil Fumarate (TDF) on Renal Function in Elderly Veterans

Abstract

BackgroundA new formulation of tenofovir with alafenamide (TAF) has been introduced that promises to reduce the risk of renal disease. However, the clinical impact of TAF in elderly persons with HIV/AIDS and comorbid renal disease has not been fully investigated. Using patient data from Louis Stokes Cleveland VA Medical Center, this study examines the effect of TDF discontinuation on renal function.MethodsWith IRB approval, clinical data from 272 veterans with HIV/AIDS were gathered to estimate glomerular filtration rate (eGFR) using CKD-EPI (CE) and Cockcroft-Gault (CG) formulae.Results122 patients were excluded because they did not meet the criteria for the study or for insufficient data. The remaining 150 patients had a mean age of 57.7 years, 96.7% were male, 51% African American, 50% were smokers, 28% had diabetes and 63% had vascular disease risk factors. Baseline mean sCR value was 1.1 ± 0.3. Mean CD4 was 672 ± 372 on TDF containing regimens (703 ± 344 after switch) and 66% (69%) had viral loads <20 cp/mL. Serum creatinine (sCr) values before and after the discontinuation of TDF were collected, and eGFR and rate of change for eGFR and sCr were calculated. In a univariate manner, variables were also examined within 3 subgroups: smokers, diabetics and patients with vascular disease risk factors. Changes in boosting medication were rare (5 patients started cobicistat and 7 patients discontinued ritonavir) and thus had little effect on average changes in sCr and eGFR in this cohort. Overall, discontinuation of TDF stabilized sCR (Figure 1). Mean sCr increased by 0.13 and eGFR declined by 5.755 (CE) or 11.822 (CG) during the mean 181 days of observation prior to TDF discontinuation. After the switch, mean sCr increased by 0.002 during a mean of 396 days of observation; eGFR increased by 1.198 (CE) or 1.300 (CG). Similar trends were observed in the 3 subgroups. In all groups, discontinuation of TDF led to improvement in eGFR.ConclusionDiscontinuation of TDF and initiation of TAF or other non TDF containing regimen stabilizes eGFR in elderly men with HIV and underlying risk for renal disease. Disclosures All authors: No reported disclosures.