Posaconazole: A Pharmacoeconomic Review of its Use in the Prophylaxis of Invasive Fungal Disease in Immunocompromised Hosts

Posaconazole (Noxafil) is an oral, second-generation, extended-spectrum triazole whose approved indications include prophylaxis of invasive fungal disease (IFD) in immunocompromised patients. In pivotal head-to-head trials, posaconazole was significantly more effective in preventing IFD than standard azole therapy (i.e. oral fluconazole or itraconazole) in chemotherapy-induced neutropenic patients with acute myelogenous leukaemia (AML) or myelodysplastic syndromes (MDS) and was noninferior to treatment with fluconazole in patients with graft-versus-host disease (GVHD) who were receiving intensive immunosuppressive therapy following haematopoietic stem cell transplantation. In both indications, prophylactic posaconazole was associated with signficantly lower rates of IFD-related mortality. The overall tolerability profile of posaconazole was generally similar to that of the other prophylactic treatments. The large body of modelled cost-effectiveness analyses from a healthcare payer perspective on the use of prophylactic posaconazole suggest that it is a dominant or cost-effective option relative to prophylaxis with standard azole therapy in neutropenic patients with AML/MDS, and fluconazole in patients with GVHD. Based on clinical trial data in these patient groups, antifungal prophylaxis with posaconazole was predicted to be a dominant or cost-effective option relative to prophylaxis with standard oral azoles, with regard to the incremental cost per QALY gained, life-year (LY) gained and/or other outcomes in cost-effectiveness analyses in numerous countries. In those analyses in which posaconazole did not dominate the comparator, posaconazole was considered cost effective, as the incremental cost per QALY or LY gained with posaconazole was lower than assumed willingness-to-pay thresholds. Sensitivity analyses consistently demonstrated that these results were robust to plausible changes in key model assumptions. In conclusion, prophylactic treatment with posaconazole is clinically effective in preventing IFD in neutropenic patients with AML/MDS and patients with GVHD. Available pharmacoeconomic data from several countries, despite some inherent limitations, support the use of posaconazole as a dominant or cost-effective prophylactic antifungal treatment relative to prophylaxis with standard oral azoles in these patient populations at high risk of developing IFD.