The anti-emetic efficacy of intravenous dolasetron mesilate plus dexamethasone versus intravenous dolasetron mesilate alone in patients receiving fractionated chemotherapy

Purpose: Fractionated cisplatin-containing regimens are routinely used for chemotherapy of certain types of cancer: Dolasetron has been shown to be ef fective in preventing,acute emesis related to cisplatin chemotherapy over 2 4 h; its effectiveness has not been evaluated in fractionated cisplatin-con taining chemotherapy. This trial assesses the efficacy of dolasetron alone or dolasetron plus dexamethasone in preventing nausea and vomiting related to fractionated cisplatin chemotherapy. Patients and Methods: 96 hospitaliz ed cancer patients were randomized to receive 100 mg i.v. dolasetron or 100 mg i.v. dolasetron + 20 mg dexamethasone before chemotherapy primarily wit h cisplatin (15-50 mg/m(2)) infused over less than or equal to 4 h for at l east 2 but not more than 5 consecutive days. Dolasetron was administered to all patients 30 min before chemotherapy. Dexamethasone or placebo was admi nistered in double-blind fashion 5 min before chemotherapy. Efficacy was me asured at hour 24 of each study day using complete response (no vomiting an d no rescue medication) and maximum nausea severity, self-assessed by patie nts using a 100-mm visual analogue scald. Results: Overall complete respons e rates were significantly higher in the dolasetron pins dexamethasone grou p compared with the dolasetron-only group (p < 0.003, Fisher's exact test). Complete response rates on study days 1 and 2 were also significantly high er with dolasetron plus dexamethasone than with dolasetron alone (day 1: 98 vs. 70%, p = 0.0290; day 2: 89 vs. 62%, p = 0.0286 by Fisher's exact test) . Test results were not significant on days 3-5 due to the small number of patients (day 3: n = 37, day 4: n = 32; day 5: n = 24). Treatment and locat ion of the primary tumor exerted the only statistically Significant effects on complete response (treatment: p = 0.006; location of primary tumor: p = 0.021 by log linear analysis of contingency tables). Both treatments were administered safely. Conclusion: As seen with other 5-HT3 receptor antagoni st antiemetics, the addition of dexamethasone to dolasetron significantly i ncreases effectiveness in preventing nausea and vomiting related to fractio nated cisplatin chemotherapy. Both dolasetron and dolasetron plus dexametha sone were well tolerated.