Comparative clinical effectiveness of various 5-HT3 RA antiemetic regimens on chemotherapy-induced nausea and vomiting associated with hospital and emergency department visits in real world practice

Purpose The aim of this study was to compare the risk of chemotherapy-induced nausea and vomiting (CINV) events for various 5-HT3 RAs in patients who received moderately (MEC) or highly emetogenic chemotherapy (HEC) by evaluating hospital or emergency department (ED) admissions. Methods PharMetrics claims database was used to identify patients diagnosed with breast cancer (BC) who were initiated on cyclophosphamide-based adjuvant chemotherapy or with lung cancer (LC) initiated on carboplatin-based or cisplatin-based chemotherapy between 2005 and 2008. Patients were stratified in two groups: those initiated and maintained on palonosetron versus those treated with any other 5-HT3 RA regimens in the 6-month post first chemotherapy. Risk for CINV events, identified by ICD-9-CM for nausea, vomiting, and/or dehydration, were estimated using logistic regressions, controlling for age, gender, comorbidity, and total chemotherapy doses or days. Results Of the 4,868 cyclophosphamide-treated BC, 5,414 carboplatin-treated LC, and 1,692 cisplatin-treated LC identified, there were 1,864 BC (38.5%), 1,806 carboplatin-treated LC (33.4%), and 390 cisplatin-treated LC (23.0%) in the palonosetron-only group. Palonosetron-only group had significantly lower probability of CINV events associated with ED/hospital admissions in all three cohorts (3.5% vs. 6.3% in BC, 9.5% vs. 13.8% in carboplatin-treated LC, and 16.4% vs. 22.6% in cisplatin-treated LC, all at p<0.05). Logistic regressions found palonosetron-only group had significantly lower risk of CINV events (odds ratios=0.550, 0.653, and 0.689 in BC, carboplatin-treated LC and cisplatin-treated LC, respectively, p<0.05). Conclusion Patients with lung or breast cancer receiving MEC or HEC had significantly lower risk of CINV events associated with hospital/ED admissions if initiated and maintained on palonosetron relative to patients receiving 5-HT3 RA regimens.