A retrospective comparison of clarithromycin versus rifampin in combination treatment for disseminated Mycobacterium avium complex disease in AIDS: clarithromycin decreases transfusion requirements.

SETTING: Urban county medical center.

OBJECTIVE: To compare clinical outcomes associated with two treatment regimens for AIDS-associated disseminated Mycobacterium avium complex (DMAC). From 1989 to mid-1992, patients were treated with rifampin, ethambutol, and clofazimine; in mid-1992 clarithromycin replaced rifampin.

DESIGN: A retrospective review of patients with DMAC; the main outcome measures assessed were toxicity associated with DMAC treatment, transfusions after the diagnosis of DMAC, and survival.

RESULTS: 88 patients received the rifampin-based regimen and 86 were treated with the clarithromycin-based regimen. Drug-related adverse events were recorded less frequently with clarithromycin treatment (21% vs. 42%, P = 0.005), and additional antimycobacterial agents were used less often (28% vs. 44%, P = 0.04). In a multivariate logistic regression model, severe anemia at the time of DMAC diagnosis was associated with transfusion-dependence (relative risk [RR] 5.6, 95% confidence interval [CI] 2.2, 13.8, P < 0.001) and clarithromycin treatment was inversely associated with transfusion dependence (RR 0.4, 95% CI 0.1, 0.98, P = 0.04). In a multivariate Cox regression model including other factors affecting survival, clarithromycin treatment did not confer a survival advantage (P = 0.74).

CONCLUSIONS: The clarithromycin-containing regimen was better tolerated and was associated with substantially lower transfusion requirements than the rifampin-based regimen; survival was not affected.