2491. Virologic Response of Switching Tenofovir Disoproxil Fumarate (TDF)-Based Regimen to Abacavir (ABC)-Based Regimen vs. Lopinavir/Ritonavir(LPV/r) Plus Lamivudine(3TC) in HIV-Infected Patients with TDF-Induced Nephrotoxicity at 24 Weeks: A Prospective, Open-Label, Randomized, Controlled Trial

Abstract

BackgroundTenofovir disoproxil fumarate (TDF)-induced nephrotoxicity is a well-recognized complication and one of the reasons for treatment switching in HIV-infected patients. Salvage regimens in renal impairment such as abacavir(ABC)-based regimen or two-drug regimens such as boosted protease inhibitor (PI) plus lamivudine (3TC) are the options for switching. However, ABC is contraindicated in patients with a high risk for cardiovascular disease. In resource-limited setting, only some PIs such as lopinavir and atazanavir are available options.MethodsWe conducted a prospective, open-label, randomized controlled trial in a tertiary center in Bangkok. We recruited HIV-infected adults who had viral suppression, with TDF-induced proximal tubulopathy and/or a significant decrease in estimated glomerular filtration rate(eGFR). The patients were randomized to receive ABC/3TC plus efavirenz (ABC-based regimen) or LPV/r+3TC. The primary outcome was the proportion of patients with viral suppression at 24 weeks. The secondary outcomes were the immunologic response, recovery of eGFR, proximal tubular function and change in lipid profile at 24 weeks.ResultsBetween August 2018 - February 2019, we screened 87 patients and enrolled 24 patients were randomly assigned to the ABC-based regimen and 23 patients to LPV/r+3TC regimen. In the intention-to-treat population, virologic response at 24 weeks was noted in 21 (87.5%) patients assigned to ABC-based regimen and 19 (82.6%) patients assigned to LPV/r+3TC regimen (P = 0.635). There were no differences in the improvement of the percentage change of eGFR, fractional excretion of phosphate, renal tubular reabsorption of phosphate (TmP/GFR), fractional excretion of uric and UPCI at 24 weeks. Triglyceride levels were significantly increased in LPV/r+3TC regimen compared with ABC-based regimen at 24 weeks (91.32% vs. 20.46%; P = 0.001).ConclusionOur study showed no difference in virologic suppression after switching to ABC-based regimen or LPV/r+3TC regimen in patients with TDF-induced nephrotoxicity. There was no difference in percentage change of eGFR, recovery of proximal tubular function in both arms after discontinuation of TDF. There was a significant change in triglyceride levels in LPV/r +3TC regimen.Disclosures All authors: No reported disclosures.