Potential role of rifabutin in prophylaxis for tuberculosis and infections due to multiple opportunistic pathogens

Patients with advanced human immunodeficiency virus (HIV) disease are at risk for infections caused by protozoa, fungi, viruses, bacteria, and mycobacteria. Chemoprophylaxis is being used increasingly to prevent a growing number of opportunistic infections that occur in HIV-infected patients. Multiple opportunistic pathogen prophylaxis (MOPP) is based on the concept that use of antimicrobial agents with activity against a variety of opportunistic pathogens will result in better patient compliance, reduced toxicity, fewer drug interactions, and lower cost than does the use of numerous single agents focused on only one infection. The antimycobacterial agent rifabutin is a potential candidate for use as MOPP because of its current status as a prophylactic agent for Mycobacterium avium complex infection. Rifabutin is likely to prevent other mycobacterial infections, including tuberculosis. The possible efficacy of rifabutin therapy for bacterial infections and toxoplasmosis deserves further study. We discuss approaches to the evaluation of rifabutin in MOPP regimens, the characteristics that make it potentially useful as prophylaxis for tuberculosis, and the potential limitations associated with its use for this indication.