A randomized, double-blind trial comparing azithromycin and clarithromycinin the treatment of disseminated Mycobacterium avium infection in patientswith human immunodeficiency virus

Two hundred and forty-six patients infected with human immunodeficiency vir us (HIV) who also had disseminated Mycobacteiium avium complex received eit her azithromycin 250 mg every day, azithromycin 600 mg every day, or clarit hromycin 500 mg twice a day, each combined with ethambutol, for 24 weeks. S amples drawn from patients were cultured and clinically assessed every 3 we eks up to week 12, then monthly thereafter through week 24 of double-blind therapy and every 3 months while on open-label therapy through the conclusi on of the trial. The azithromycin 250 mg arm of the study was dropped after an interim analysis showed a lower rate of clearance of bacteremia, At 24 weeks of therapy, the likelihood of patients' developing 2 consecutive nega tive cultures (46% vs. 56%, P = .24) or 1 negative culture (59% vs. 61%, P =.80) was similar for azithromycin 600 mg (n = 68) and clarithromycin (n = 57), respectively. The likelihood of relapse was 39% versus 27% (P = .21) o n azithromycin compared with clarithromycin, respectively. Of the 6 patient s who experienced relapse, those randomized to azithromycin developed isola tes resistant to macrolides, compared with 2 of 3 patients randomized to cl arithromycin. Mortality was similar in patients comprising each arm of the study (69% vs. 63%; hazard, 95.1% confidence interval, 1.1 [0.7, 1.7]), Azi thromycin 600 mg, when given in combination with ethambutol, is an effectiv e agent for the treatment of disseminated M. avium disease in patients infe cted with HIV.