Cost-Effectiveness of Prophylaxis for Mycobacterium avium Complex Disease

Abstract

There are now several alternative drug regimens that have been shown to be effective in preventing Mycobacterium avium complex (MAC) disease in human immunodeficiency virus (HIV)-infected patients. The effectiveness and the costs of these drugs should be taken into account when choosing a specific drug regimen, as the cost of treating MAC can be relatively high. Our results are formulated from an analysis to assess the comparative cost-effectiveness of available prophylactic drugs for MAC. A decision analysis was undertaken comparing no prophylaxis and prophylaxis with either rifabutin, clarithromycin, azithromycin, or azithromycin and rifabutin in combination. Estimates of effectiveness of prophylaxis and costs of illness were obtained from published literature. Drug costs were based on national average wholesale prices. Sensitivity analyses were done over plausible ranges of estimates of cost and effectiveness. Given our baseline assumptions, the most cost-effective regimen in regard to cases of avoided MAC or death is azithromycin used alone. Clarithromycin used alone is the next most cost-effective approach. Combination therapy with azithromycin and rifabutin is less cost-effective than macrolide monotherapy, and rifabutin used alone is less cost-effective than any of the macrolide-containing regimens. Using some type of MAC prophylaxis is preferable to no prophylaxis when considering cost as well as efficacy. At current prices and using currently available effectiveness data, azithromycin is probably the most cost-effective choice of prophylactic therapy for MAC. Not using MAC prophylaxis is the least cost-effective option. Prevention of MAC with drug therapy provides clinical benefit at a reasonable cost.