RT Journal A1 Yeni PG, Hammer SM, et al T1 UNderpowered clinical trials of antiretroviral treatment—reply JF JAMA JO JAMA YR 2002 FD November 6 VO 288 IS 17 SP 2120 OP 2121 DO 10.1001/jama.288.17.2118 UL http://dx.doi.org/10.1001/jama.288.17.2118 AB In Reply: We agree with Drs Arribas and Pulido that insufficient statistical power may limit the conclusions drawn from a comparative clinical study and their value for treatment recommendations. However, we believe that the 2 studies1- 2 they cited deserved to be cautiously mentioned in our recommendations because, despite limitations, they bring scientific information pertinent for discussing therapy with nevirapine in treatment-naive patients. In the COMBINE study,2- 3 for instance, in which 142 patients were enrolled, the proportion of patients with plasma HIV-1 RNA level below detection limits after 1 year of therapy was 75% in the nevirapine-containing arm and 60% in the nelfinavir-containing arm,3 allowing the authors to conclude that "zidovudine/lamivudine/nevirapine is at least as effective as zidovudine/lamivudine/nelfinavir as first-line therapy."