Objectives: Recently published studies have demonstrated increased efficacy and cost-effectiveness of combination therapy with interferon and α-2b/ribavirin compared with interferon-alpha monotherapy in the treatment of chronic hepatitis C (CHC). Combination therapy is associated with a clinically important adverse effect: ribavirin-induced hemolytic anemia (RIHA). The objective of this study was to evaluate the direct health-care costs and management of RIHA during treatment of CHC in a clinical trial setting.
Methods: A systematic literature review was conducted to synthesize information on the incidence and management of RIHA. Decision-analytic techniques were used to estimate the cost of treating RIHA. Uncertainty was evaluated using sensitivity analyses.
Results: RIHA, defined as a reduction in hemoglobin to less than 100 g/L, occurs in approximately 7% to 9% of patients treated with combination therapy. The standard of care for management of RIHA is reduction or discontinuation of the ribavirin dosage. We estimated the direct cost of treating clinically significant RIHA to be $170 per patient receiving combination therapy per 48-week treatment course (range $68–$692). The results of the one-way sensitivity analyses ranged from $57 to $317. In comparison, the cost of 48 weeks of combination therapy is $16,459.
Conclusions: The direct cost of treating clinically significant RIHA is 1% ($170/$16,459) of drug treatment costs. Questions remain about the optimal dose of ribavirin and the incidence of RIHA in a real-world population. Despite these uncertainties, this initial evaluation of the direct cost of treating RIHA provides an estimate of the cost and management implications of this clinically important adverse effect.