Olanzapine –The cost-effective anti-emetic

ABSTRACT Introduction: Chemotherapy induced nausea and vomiting can be distressing when not adequately controlled. Many agents are used prophylactically to prevent CINV (Chemotherapy induced nausea and vomiting). Olanzapine is an atypical antipsychotic with anti-emetic property and has showed promise in the prevention of delayed emesis and nausea. Recent comparisons of olanzapine and aprepitant based combinations have shown non - inferiority of both the drugs. Objective: The aim of this study is to compare the efficacy, tolerability and cost effectiveness of olanzapine based regimen. Materials and Methods: This is a prospective, non-randomized observational comparative study conducted from March 2021 to June 2021. All the patients undergoing treatment with high emetogenic chemotherapy were screened. Forty patients in each arm with a maximum of four cycles per patient were non-randomly assigned to either of the arms, arm A - OPD (Olanzapine, Palonosetron, Dexamethasone) and arm B – APD (Aprepitant, Palonosetron, Dexamethasone), prospectively. All the data are entered in Microsoft excel spread sheet. Range, mean and median values are calculated in excel. Data was analyzed using SPSS software version 26. Results: For emesis, the CR Complete Remission) rates for emesis in the OPD arm were recorded as 89.3% during acute (0 to 24 hours), 87.5% during delayed (24 to 120 hours) and 80.6% during overall period. The CR rates in APD arm were recorded as 90.6% during the acute period, 86.2% during the delayed period and 81.25% during the overall period. In the OPD arm, CR for nausea was observed in 87.5% during acute period, 88.75% during delayed period and 85% during overall period. Whereas in the APD arm, no nausea was observed in 88.75% during acute period, 89.3% during delayed period and 84.3% during overall period. The differences between the two arms were not statistically significant with respect to emesis and nausea for acute, delayed and overall periods ( P > 0.05). Both the regimens were well tolerated overall. In the Olanzapine arm, sedation and excessive sleepiness (10%) were observed frequently and all were grade 1. Giddiness was seen in 5%, headache in 5% and pain abdomen in 2.5% of the OPD patients. In the aprepitant arm, pain abdomen (7.5%) constipation (5%) and fatigue (5%), headache (5%) were the most frequently observed adverse events. All were grade 1 according to the CTCAE (Common Terminology Criteria for Adverse Events) and were self -limiting. The difference between the arms was not statistically significant ( P = 0.065) using chi- square test. On direct comparison, Aprepitant is 30 times costlier than olanzapine. Conclusion: Olanzapine could prevent chemotherapy induced nausea and vomiting in comparison with aprepitant. Olanzapine was also well tolerated and anti-emetic regimen could be completed with a lesser cost.