A Randomized Comparative Trial of Continued Abacavir/Lamivudine plus Efavirenz or Replacement with Efavirenz/Emtricitabine/Tenofovir DF in Hypercholesterolemic HIV-1 Infected Individuals

Background Drug choice and metabolic changes with antiretroviral therapy contribute to cardiovascular risk in persons with HIV-1 infection. Methods A randomized, 12 week, open-label, comparative study of the impact on lipids of continuation of abacavir/lamivudine (ABC/3TC) plus efavirenz (EFV) or replacement with the single tablet regimen of EFV/emtricitabine/tenofovir DF (EFV/FTC/TDF) in hypercholesterolaemic subjects on successful antiretroviral therapy, with a 12-week extension with all subjects on EFV/FTC/TDF. Results 157 subjects received study drug, 79 switched to EFV/FTC/TDF and 78 subjects continued ABC/3TC+EFV. At Week 12, 73 subjects on ABC/3TC+EFV switched to EFV/FTC/TDF. The switch was well tolerated and no subject experienced viral rebound. Median baseline fasting total cholesterol was 6.32mmol/L. 12 weeks following switch, the difference in the means (LSM) between treatment groups (EFV/FTC/TDF minus ABC/3TC+EFV) in total cholesterol change from baseline was -0.74mmol/l (95% CI -1.00, -0.47, p < 0.001). The median change from baseline in total cholesterol following switch in the EFV/FTC/TDF arm was -0.86mmol/l (p < 0.001) compared with +0.01mmol/l (p = 0.45) in the continuation arm at Week 12. Significant (p < 0.001) differences between treatment groups following switch were seen for all lipid fractions from baseline to Week 12: LDL cholesterol (-0.47 mmol/L [-0.70, -0.25]), HDL cholesterol (-0.15 mmol/L [-0.21, -0.08]), triglycerides (-0.43 mmol/L [-0.75, -0.11]), and non HDL cholesterol (-0.56 mmol/L [-0.80, -0.31]). In the extension phase, similar declines in total cholesterol were observed with a median change from Week 12 to Week 24 of -0.73mmol/L (p < 0.001). Conclusions Switching from ABC/3TC+EFV to EFV/FTC/TDF in persons with hypercholesterolemia maintains virological control and significantly improves key lipid parameters.