Randomized, Placebo-Controlled Trial of Rifampin, Ethambutol, and Ciprofloxacin for AIDS Patients with Disseminated Mycobacterium avium Complex Infection

Patients with AIDS and disseminated Mycobacterium avium complex (MAC) infection received rifampin (600 mg) plus ethambutol (25 mg/kg) plus ciprofloxacin (750 mg) or matching placebos daily for 8 weeks. Patients were monitored every 2 weeks clinically and by quantitating MAC colony-forming units (cfu) per milliliter of blood. Analysis of baseline characteristics revealed no significant differences between groups. After 8 weeks, MAC cfu had decreased by ⩾1 log/mL in 4 of 9 treated patients versus 0 of 10 placebo recipients while increasing by ⩾1 log/mL, in 1 and 7, respectively (P =.006). While the average combined clinical response score declined in both groups, it tended to decrease less in treated patients (P =.36). On the other hand, dose-limiting toxicity (primarily nausea and adverse drug interactions) occurred in 9 of 12 treatment versus 1 of 12 placebo patients (P =.005). Combined rifabutin-ethambutol-ciprofloxacin therapy for disseminated MAC infection had significant microbiologic efficacy with some evidence of clinical efficacy but was associated with drug intolerance.