Background:  In treatment-naive patients given 48 weeks of therapy, raltegravir (RAL) +tenofovir (TDF)/emtricitabine (FTC) had non-inferior antiretroviral activity compared to EFV+TDF/FTC and was associated with greater increases in CD4 cell counts.

Methods:  Patients with HIV RNA levels >5000 copies/mL and no resistance to EFV, TDF or FTC were eligible for a blinded randomized study of RAL (400 mg twice daily) vs EFV (600 mg every hour of sleep), each with TDF/FTC. Stratification was by screening RNA (≤/> 50,000 copies/mL) and hepatitis status. Results for the primary and secondary endpoints (percentage of patients achieving RNA <50 copies/mL and <400 copies/mL at week 48, and change from baseline in CD4 cell count at week 48) were summarized within several prespecified subgroups in order to further characterize the effect of RAL. Summary statistics were provided by treatment group within each subgroup using the observed failure approach.

Results:  Of 563 treated patients, 19% were female and 58% were non-white; region of residence was Latin America (35%), North America (31%) and EU/Australia (23%); median age was 37 years; 53% had vRNA >100,000 copies/mL, 48% had CD4 counts <200 cells/mm³ at entry, and 19% were infected with non-subtype B HIV. RAL and EFV had virologic efficacy that was generally consistent across baseline demographic factors. The table summarizes the proportion of patients with vRNA <50 copies/mL at week 48 by selected baseline factors. RAL demonstrated greater CD4 cell increases than EFV at week 48 that was consistent across baseline demographic factors. RAL was in general well tolerated.

Conclusions:  RAL demonstrated consistent virologic and immunologic efficacy across demographic and all baseline prognostic factors including baseline plasma vRNA >100,000 copies/mL, baseline CD4 ≤50 cells/mm³, gender/racial groups, and viral subtypes.