Characterization of Nabilone for the Treatment of Chemotherapy-Induced and Refractory Nausea and Vomiting

Abstract

Background: Chemotherapy-induced nausea and vomiting (CINV) significantly impacts cancer patients. Studies on the use of cannabinoids for breakthrough and refractory CINV are limited. Objectives: The primary objective was to characterize the use of nabilone at Princess Margaret Cancer Centre (PM). Secondary objectives were to describe the efficacy and safety of nabilone in CINV. Methods: A prospective patient survey and chart review was conducted for adult inpatients at PM prescribed nabilone for nausea or vomiting between February and June 2024. Indications, prescribing and use patterns were collected from patient charts. The survey assessed the degree of CINV using the Common Terminology Criteria for Adverse Events (CTCAE) grades for nausea, vomiting and adverse effects after 5 days of nabilone treatment. Results: Nabilone was prescribed in 24 patients. Nausea and/or vomiting was the most common indication, prescribed in 18 patients (75%). Out of this group, 13 patients (72%) were past 5 days from chemotherapy. Eight patients met inclusion criteria and consented to enrollment. Five patients (62.5%) started nabilone within 5 days of chemotherapy (breakthrough CINV), and 3 patients (37.5%) started after 5 days (refractory nausea/vomiting). Six patients (75%) were prescribed guideline-directed antiemetic prophylaxis. Four patients (50%) received highly emetogenic chemotherapy, and 6 (75%) tried at least 6 antiemetics prior to nabilone, including olanzapine in 5 (62.5%). The most frequent regimen was 0.5-1 mg once to twice daily for a mean duration of 6.4 days +/- 5 days. The mean change in nausea CTCAE grade was -0.25 +/- 0.83, which improved in 2 patients (25%). Vomiting improved in 1 patient (12.5%). The most frequently reported adverse events were drowsiness (87.5%) and dry mouth (75%). Conclusion: In the majority of patients who were prescribed nabilone at PM, use was reserved for nausea and/or vomiting refractory to first-line antiemetics. This aligns with current guideline recommendations for cannabinoids in CINV. Despite the small sample size, nabilone use appeared safe and effective in some patients. Nabilone as a therapeutic alternative for CINV should be further evaluated in a clinical trial.