2025 Southeastern Residency Conference

SAFETY AND EFFICACY OF IV FOSAPREPITANT VERSUS IV APREPITANT Ha Nguyen Trinh, Sajia Kotwal, Karishma Patel Emory Decatur Hospital, Decatur, GA 
Background/Purpose: Chemotherapy-induced nausea and vomiting (CINV) remains a common and distressing side effect that can have a negative impact on the quality of cancer patients’ lives. Neurokinin-1 receptor antagonists (NK1RAs) effectively prevent CINV for moderate to high emetogenic chemotherapy regimens. The two most common NK1RAs are aprepitant and fosaprepitant. While IV fosaprepitant has been shown to be non-inferior to aprepitant, it is associated with a higher incidence of infusion-related adverse reactions (IRARs), compared to IV aprepitant. This occurs because IV fosaprepitant contains polysorbate 80, a surfactant known to increase the risk of hypersensitivity and IRARs. Both agents have been used for CINV prevention; however, IV fosaprepitant has recently become the preferred formulary NK1RA at our institution. This research project aimed to compare the safety and efficacy of IV fosaprepitant and IV aprepitant in patients who received chemotherapy inpatient and at the outpatient infusion center at Emory Decatur Hospital (EDH).  

Methods: This study was a single-center, retrospective analysis of 86 patients aged 18 years or older who received either IV fosaprepitant or IV aprepitant as part of the antiemetic regimen for CINV at EDH between October 2022 and August 2024. Patients who were intolerant to either agent, received either agent for indications other than CINV or received oral aprepitant were excluded. The primary outcome was the incidence of IRARs, characterized by injection site pain, swelling, erythema, phlebitis, thrombophlebitis, and hypersensitivity (e.g., hypotension or hypertension, dyspnea, bronchospasm, edema, blisters, rash, flushing, chills or fever). Secondary outcomes included CINV complete response (CR) rates in the acute phase (defined as the absence of vomiting and use of rescue medications within 24 hours), number of vomiting episodes, use of rescue medications for breakthrough emesis, incidence of discontinuation and the incidence of switching from one NK1RA to another NK1RA. Descriptive statistics were used to summarize baseline characteristics, primary and secondary outcomes. Continuous variables were reported as means +/- standard deviation or median with interquartile ranges, while categorical variables were expressed as frequencies and percentages. Primary and secondary outcomes were compared using odds ratio (OR), 95% confidence interval (CI), and p-value of 0.05. 

Results:  For the primary outcome, there were no incidences of infusion reactions in the IV aprepitant group but there were 5 (11.4%) incidences of infusion reactions in the IV fosaprepitant group (p = 0.025, OR = 11, 95% CI [0.6 - 205]). There was no significant difference in CINV CR rates between the two groups (p = 0.64, OR = 1.8, 95% CI [0.1 - 2.4]). No patients reported experiencing vomiting episodes. Both groups had low and similar incidences of the use of rescue medications or breakthrough nausea (p = 0.62, OR = 0.71, 95% CI [0.2 - 3.4]). There were 5 incidences of discontinuation or switching from fosaprepitant to aprepitant (p = 0.025, OR = 11, 95% CI [0.6 - 205]). 

Conclusions: Both IV fosaprepitant and IV aprepitant were effective in CINV prevention. However, IV fosaprepitant was associated with a higher incidence of infusion-related adverse reactions.