P-116: CHEMOTHERAPY RELATED NAUSEA AND VOMITING PROPHYLAXIS WITH APREPITANT FOR PATIENTS RECEIVING HIGH DOSE MELPHALAN FOLLOWED BY HSCT: A COST UTILITY ANALYSIS (CUA)

Introduction: patients that receive myeloablative doses of melphalan are considered to be at high risk for chemotherapy induced nauseas and vomiting (CINV). A combination of aprepitant, granisentron and dexamethasone is more efficacious than the combination of only anti 5-HT and corticosteroids. The objective of the present CUA is to define the cost-effectiveness of triplet anti-emetic regimen from a private health care provider perspective.

Methods: A Markov model of 4 states (complete response and three states of nausea) was developed to compare a triplet (NK1, 5-HT, Corticosteroids) with a double (5-HT, Corticosteroids) for expected costs and outcomes. The transition probabilities were estimated from a prior randozimed controlled trial (Schmitt et al., J Clin Oncol, 2014). Model assumptions were that a patient would never ‘come back’ from a previous nausea estate, costs with medication were estimated with Brazilian currency according to maximum prices allowed by sanitary authorities. The comparator strategy of doublet did not include aprepitant as a rescue option. We also calculated the cost per additional patient on complete response at 7 days as well as the cost per patient-day in complete response.

Results: Seven days after a single day infusion of melphalan, 63% patients receiving the a triplet prophylactic regimen remained in complete response (that is the absence of nausea or vomiting) as compared to 21% of patients receiving a doublet regimen. The use of aprepitant at a mean cost of R$ 351,00 resulted in an overall mean increment of 0,014 gain in quality of life adjusted year. The incremental cost effectiveness ratio was R$ 22.281,63/QALY. The cost per additional patient on complete response at 7 days was R$ 777,10 and the cost per patient day in complete response was R$ 144,39.

Conclusions: The result of the present CUA suggest that aprepitant is cost-effective for the prevention of CINV given a commonly accepted willingness to pay threshold of R$ 100.000/QALY.