EFFICACY AND TOLERABILITY OF ORAL ONDANSETRON VERSUS PROCHLORPERAZINEIN THE PREVENTION OF EMESIS ASSOCIATED WITH CYCLOPHOSPHAMIDE-BASED CHEMOTHERAPY AND MAINTENANCE OF HEALTH-RELATED QUALITY-OF-LIFE

This study compared the efficacy and tolerability of oral ondansetron (8 mg twice daily [BID] for up to 3 days) with these of phenothiazine prochlorperazine (10 mg BID for up to 3 days) in 133 cancer patients r eceiving cyclophosphamide-based chemotherapy. In addition, the study e valuated the impact of these treatments on patients' health-related qu ality of life, measured with both the Functional Living Index-Cancer a nd the Functional Living Index-Emesis questionnaires. The first dose o f study drug was administered 30 minutes before initiation of chemothe rapy. Patients received a rescue antiemetic at their request or if the investigator deemed it necessary. There was a statistically significa nt difference in the number of patients with no emetic episodes over t he 3-day study period: 60% in the ondansetron group compared with 21% in the prochlorperazine group. Twenty-five percent of ondansetron-trea ted patients compared with 68% of prochlorperazine-treated patients ex perienced three or more emetic episodes, rescue medication use, or wit hdrawal from the study due to adverse events or lack of efficacy of th e study drug. Among patients with at least one emetic episode, the mea n time to emesis was significantly longer (13 hours and 37 minutes) in the ondansetron group compared with the prochlorperazine group (9 hou rs and 30 minutes). Nausea and appetite scores did not differ signific antly between groups. The score on the vomiting subscale of the Functi onal Living Index-Emesis was significantly more favorable in the ondan setron group compared with the prochlorperazine group, indicating bett er maintenance of health-related quality of life in ondansetron-treate d patients. Both treatments were well tolerated. The most common poten tially drug-related adverse event was headache, which occurred in sign ificantly more (16%) ondansetron-treated patients compared with prochl orperazine-treated patients (3%). The results of this study demonstrat e that oral ondansetron 8 mg BID for up to 3 days is more effective th an prochlorperazine 10 mg BID for up to 3 days in the prevention of em esis associated with moderately emetogenic chemotherapy.