A randomized clinical trial comparing nelfinavir or nevirapine associated to zidovudine/lamivudine in HIV-infected naive patients (the Combine Study).

BACKGROUND Non-nucleoside reverse transcriptase inhibitor-containing regimens may be a valid alternative to protease inhibitor-containing regimens for initial antiretroviral therapy, but to date few studies comparing these two strategies have been performed. OBJECTIVE To evaluate the efficacy and safety of nelfinavir or nevirapine associated to zidovudine/lamivudine in HIV-infected naive patients. DESIGN Randomized, open-label, multicentre trial. SETTING Twelve centres in Spain (9) and Argentina (3). PATIENTS One hundred and forty-two HIV-infected naive patients without AIDS. INTERVENTIONS Patients received combivir (zidovudine 300 mg/lamivudine 150 mg, twice-daily) plus either nelfinavir (1250 mg) twice-daily (zidovudine/lamivudine/nelfinavir, n=70) or nevirapine (200 mg) twice-daily (zidovudine/lamivudine/nevirapine, n=72), and were followed for 12 months. The primary endpoint was the proportion of patients with a plasma HIV-1 RNA (pVL) of less than 200 copies/ml by PCR at 12 months. pVL of less than 20 copies/ml (PCR), changes in CD4 counts, clinical progression and adverse events were also evaluated. Efficacy was assessed using intent-to-treat (ITT) (missing=failure) and on-treatment analysis. RESULTS At 12 months in the ITT analysis the proportion of patients with pVL below 200 copies/ml was 60% (95% CI 48.5-71.5) in the zidovudine/lamivudine/nelfinavir arm and 75% (95% CI 65-85) in the zidovudine/lamivudine/nevirapine arm (P=0.06), and the proportion below 20 copies/ml was 50% (95% CI 38.3-61.7) and 65% (95% CI 54.2-76.2), respectively (P=0.06). No differences were found when comparing the subgroup of patients with baseline pVL of more than 100,000 copies/ml. A gain of +173 and +162 CD4 cells/mm3, respectively, was observed. Zidovudine/lamivudine/nelfinavir was discontinued in 21% of patients, and zidovudine/lamivudine/nevirapine in 25%, due to toxicity (P>0.2). CONCLUSIONS Our results suggest that zidovudine/lamivudine/nevirapine is at least as effective as zidovudine/lamivudine/nelfinavir as first-line therapy for HIV disease.