EFFICACY OF RIFABUTIN IN THE TREATMENT OF DISSEMINATED INFECTION DUE TO MYCOBACTERIUM-AVIUM COMPLEX

The incidence of infection with Mycobacterium avium complex (MAC) is i ncreasing among patients with AIDS. Although numerous antimicrobial re gimens have been proposed as treatment for this infection, it is uncle ar which therapy is most effective. For this reason, we prospectively evaluated rifabutin (600 mg/d) vs. a placebo, each in combination with clofazimine and ethambutol, for the treatment of MAC bacteremia. Pati ents in the rifabutin group had a significantly higher rate of microbi ological response (defined as either sterilization of the blood or at least a 2-log(10) reduction in mycobacterial titers). By week 4 of the rapy, 7 of II patients receiving rifabutin, vs. 0 of 13 in the placebo group, had responded (P <.001). Similar results were seen at later ti me points (7 of 10 vs. 1 of 8 responded to rifabutin by week 8, and 6 of 9 vs. 1 of 7 responded to a placebo by week 12). These results indi cate that, in combination with other antimicrobial agents, rifabutin m ay be effective in the treatment of disseminated MAC infection.