This key study from the series of efavirenz studies presented in Geneva looked at the effectiveness of a combination that does NOT include one of the now-traditional nucleoside reverse transcriptase inhibitors (NRTIs, such as AZT, 3TC, d4T, etc.). Instead, in this study (early results from which were first presented in San Francisco in September), patients received the protease inhibitor indinavir (IDV, 1000 mg every 8 hours) in combination with the experimental non-nucleoside reverse transcriptase inhibitor efavirenz (EFV, 600 mg once a day). Note that the indinavir dose must be increased when taken with efavirenz; this did not, however, seem to lead to an increase in side effects.

101 patients, 71% of whom had received NRTI therapy previously, were enrolled in this study, which originally randomized people to IDV alone or IDV+EFV. At week 12, patients taken IDV alone actually added both EFV and d4T. 72 weeks of data were reported in an intent-to-treat analysis in Geneva, and among patients on the IDV+EFV arm, 73% of patients had their viral loads reduced to under 400 copies per mL, and those patients saw mean increase in CD4 cell count of 243 cells per ml. For those patients who cannot tolerate NRTIs, indinavir and efavirenz in combination is an attractive option for both experienced and naïve patients.