The outcome and choice of initial combination anti-retroviral therapy in treatment-naïve HIV-infected individuals

Background : Optimization of initial highly active antiretroviral therapy (HAART) for complete viral suppression and better tolerability is paramount for the prognosis of HIV-infected patients. Durable suppression of HIV therefore depends on the use of potent, well-tolerated antiretroviral regimens to which patients can easily adhere. The aim is to determine the outcome and factors influencing the choice of initial combination antiretroviral drugs in the treatment-naive HIV patients. Methods : The outcome and factors influencing the choice of initial antiretroviral drugs were investigated in HIV-infected treatment-naive individuals in a large HIV treatment clinic in south-western Nigeria using a cross-sectional design between January to December 2010. Results : 432 patients were analyzed (mean age 38 years ± 9.010), 67.6% females, 50.1% prior AIDS. Mean CD4 cells and HIV RNA were 146 cells/mm 3 and 194312 copies/ml respectively. Zidovudine-lamivudine-nevirapine regimen (ZDV-3TC-NVP) was prescribed in 34.3%, followed by tenofovir-emtricitabine-efavirenz (TDF-FTC-EFV) 26.9%, TDF-FTC-NVP (17.6%), TDF-3TC-NVP (8%), ZDV-3TC-EFV (4.6%), abacavir (ABC)-3TC-EFV (3.7%), ABC-3TC-NVP (2.8%). Difference in prescription was noted among the doctors. Compared with TDF-3TC-NVP, starting TDF-FTC-EFV was mainly associated in multivariate analysis with reduced pill burden (P 200,000 copies/ml (P=0.0015). TDF-3TC-NVP and TDF-3TC-ZDV-atazanavir (ATV)-ritonavir (RTV) were more likely in patients with drug substitution and switch programs respectively (P<0.001; P<0.001). ABC-3TC-EFV was more likely in patients with deranged creatinine levels (P=0.002). At 6 months and 12 months, 364 (84.3%) and 392 (90.7%) achieved virologic suppression respectively (HIV RNA copies <200 copies/ml). CD4 cells increased by 138 cells/mm 3 and 198 cells/mm 3 at 6 months and 12 months respectively. Virologic suppression was more likely with TDF-FTC-EFV (93.7%) while CD4 cells increase was higher with ZDV-3TC-NVP. The 2 most common often prescribed regimens, TDF-FTC-EFV and ZDV-3TC-NVP, had virologic response rates of 93.7% and 84.2% (P<0.001). Conclusion : Factors such as physician preference and patient-reported features play a role in the choice of initial HAART regimen. Identification of these features and simplification of treatment regimens will be necessary in order to maximize the effectiveness of HAART regimens.