Pharmaco-economic analyis of posaconazole versus standard azole prophylaxis in high-risk neutropenic AML/MDS patients in Germany

Abstract number: P1031

Thalheimer M., Cornely O.A., Hoppe-Tichy T., Schuler U., Knoth H., Kiehl M., Ullmann A.J., O'Sullivan A., Ostermann H.

Objectives: The objective of our analysis was to estimate the cost-effectiveness of antifungal prophylaxis with posaconazole vs. standard azole therapy (i.e., fluconazole or itraconazole) in patients with acute myelogenous leukaemia (AML) or myelodysplastic syndrome (MDS) and at high risk of developing an IFI due to chemotherapy-induced neutropenia. Posaconazole significantly prevents invasive fungal infections (IFIs) and reduces overall mortality vs. standard azole therapy in these patients (Cornely et al. NEJM, 2007).

Methods: A decision-analytic model was developed based on the results of the large multicentre trial, extrapolated to a lifetime horizon and analysed from a German perspective.

The probabilities of experiencing an IFI, IFI-related death, and death from other causes over 100 days of follow-up were estimated from the trial data. Long-term mortality data is based on the database of a large German university clinical centre, drug costs were estimated using published sources. IFI treatment costs were derived from a multicentre retrospective chart review. Due to a lack of published data on the impact of an IFI on quality of life of AML/MDS patients, a panel of 20 hematology-oncology experts estimated this impact based on the SF-6D questionnaire. The utilities derived from the analysis of the questionnaires served to estimate the quality-adjusted life years (QALY).

The pharmacoeconomic model presented was used to estimate incremental cost per patient, incremental cost-effectiveness ratio (ICER) per life-years saved and incremental costs per quality-adjusted life years (QALY).

Results: Posaconazole is associated with fewer IFIs (0.05 vs. 0.11; p = 0.003) and slightly higher overall treatment costs (1,041 [euro]) per patient relative to standard azole therapy over a lifetime horizon. The ICER per live-years saved was 10,235 [euro]. Posaconazole prophylaxis resulted in 0.1 QALYs gained in comparison to prophylaxis with standard azoles. Results from a probabilistic sensitivity analysis indicate that there is an 81% probability that the cost per QALY gained with posaconazole is below 20,000 [euro], a commonly accepted threshold for cost-effectiveness.

Conclusion: Based on the clinical data and on the assumptions, our analysis demonstrated that posaconazole is likely to be cost-effective relative to standard azole therapy (i.e., fluconazole or itraconazole) in the prevention of IFIs among high-risk neutropenic patients.