413 - Initial Characterization of Fosaprepitant Use in Antiemetic Regimens for Pediatric Hematopoietic Stem Cell Transplant

Abstract

Background: Preparative regimens often include the use of chemotherapeutic agents with high emetogenic potential. Recent guideline updates encourage the use of neurokinin 1 antagonists in combination with corticosteroids and serotonin receptor antagonists in the pediatric population. While accumulating data has emerged to establish the safety of oral aprepitant formulations in the pediatric population, no such data exists for intravenous fosaprepitant in these patients. Fosaprepitant was used with success in the pediatric oncology population at our institution during a time of aprepitant shortage, and its use was expanded to the stem cell transplant population after initial safety was demonstrated. This review characterizes the first documented use of fosaprepitant in pediatric stem cell transplant literature and addresses a research gap recognized by current clinical practice guidelines. Methods: A retrospective review was conducted in a pilot study of five pediatric stem cell transplants using fosaprepitant in combination with corticosteroids and serotonin receptor antagonists for emesis prevention against highly emetogenic preparative regimens. Patients were evaluated for commonly reported adverse effects in adult literature including headache, diarrhea, hepatotoxicity, hypersensitivity reactions, and hiccups. The relative cost of using fosaprepitant as compared to equivalent courses of aprepitant was evaluated for each of these transplants. Results: During the five transplant courses evaluated no patients experienced acute nausea or vomiting, although two patients received breakthrough antiemetic agents during the acute time frame. One patient reported delayed nausea and experienced delayed emesis requiring breakthrough antiemetic agents in the delayed period post-transplant. No patients were documented to have experienced any adverse effects thought to be secondary to fosaprepitant usage. The relative cost of fosaprepitant for emesis prevention was less than half that of an equivalent course of aprepitant, representing a cost savings of $665 across the five transplant courses evaluated. Conclusions: Fosaprepitant appears to be a safe and economical alternative to aprepitant for emesis prevention and its use merits further investigation within the pediatric transplant population.