Cost-effectiveness of antifungal prophylaxis, preemptive therapy, or empiric treatment following allogeneic hematopoietic stem cell transplant.

Background: Invasive fungal infection (IFI) is a life-threatening complication of allogeneic hematopoietic stem cell transplantation (HSCT) that is also associated with excess healthcare costs. Current approaches include universal antifungal prophylaxis, preemptive therapy based on biomarker surveillance, and empiric treatment initiated in response to clinical signs/symptoms. However, no study has directly compared the cost-effectiveness of these treatment strategies for an allogeneic HSCT patient population.

Methods: We developed a state transition model to study the impact of treatment strategies on outcomes associated with IFIs in the first 100 days following myeloablative allogeneic HSCT. We compared three treatment strategies: empiric voriconazole, preemptive voriconazole (200 mg), or prophylactic posaconazole (300 mg) for the management of IFIs. Preemptive treatment was guided by scheduled laboratory surveillance with galactomannan (GM) testing. Endpoints were cost and survival at 100 days post-HSCT.

Results: Empiric treatment was the least costly ($147 482) and was equally effective (85.2% survival at 100 days) as the preemptive treatment strategies. Preemptive treatments were slightly more costly than empiric treatment (GM cutoff ≥ 1.0 $147 910 and GM cutoff ≥ 0.5 $148 108). Preemptive therapy with GM cutoff ≥ 1.0 reduced anti-mold therapy by 5% when compared to empiric therapy. Posaconazole prophylaxis was the most effective (86.6% survival at 100 days) and costly ($152 240) treatment strategy with a cost of $352 415 per life saved when compared to empiric therapy.

Conclusions: One preemptive treatment strategy reduced overall anti-mold drug exposure but did not reduce overall costs. Prevention of IFI using posaconazole prophylaxis was the most effective treatment strategy and may be cost-effective, depending upon the willingness to pay per life saved.