Olanzapine for Chemotherapy-Induced Nausea and Vomiting (CINV) Prophylaxis in Patients Receiving High-Dose Chemotherapy for Autologous Hematopoietic Stem Cell Transplantation (ASCT)

Abstract

Introduction Olanzapine has demonstrated clinical efficacy for CINV prophylaxis. Efficacy and safety of olanzapine for CINV prophylaxis in patients receiving high-dose chemotherapy as conditioning regimen for HSCT is not established. Objective The primary objective is to compare efficacy and safety of olanzapine versus fosaprepitant for CINV prophylaxis in patients receiving high-dose chemotherapy for ASCT. Methods A single-center, retrospective analysis evaluated consecutive patients who received high-dose melphalan or BEAM for ASCT from June 2016 to September 2018. April 2017 onwards, we switched CINV prophylaxis to olanzapine, replacing fosaprepitant. In this analysis, outcomes of an olanzapine regimen combined with ondansetron and dexamethasone (OOD) were compared with fosaprepitant combined with ondansetron and dexamethasone (FOD). Assessment period for CINV was defined as acute phase (chemotherapy days) and delayed phase (within 5 days of chemotherapy completion). The primary endpoint is the proportion of days requiring rescue CINV medications during the assessment period. Secondary endpoints include number of rescue medication doses required during the acute and delayed phases, time to neutrophil engraftment (TTNE), and length of stay (LOS). A cost-effectiveness analysis is being performed. Results A total of 154 patients were evaluated (FOD = 83 and OOD = 71). Patient demographics were similar in both groups, except that patients in the OOD cohort were older (median age 63 vs. 55 years; p = 0.0002). Patients received the following conditioning regimens: melphalan 140 mg/m2 (FOD = 10; OOD = 21), melphalan 200 mg/m2 (FOD = 28; OOD = 44), BEAM (FOD = 45; OOD = 6). In the acute phase, 10% of FOD patients required rescue CINV medications on at least 50% of days while approximately 3% of OOD patients required rescue medications on any day (p = 0.006). In the delayed phase, the median proportion of days requiring rescue CINV medications was significantly lower with OOD (60% vs. 20%; p Conclusion Olanzapine-based CINV prophylaxis was significantly superior to fosaprepitant for the proportion of days requiring rescue CINV medications.