Low Dose Olanzapine in the Prevention and Treatment of Carboplatin Induced Nausea and Vomiting: A Prospective Clinical Randomized Controlled Trial

Objective: This study aimed to determine the effectiveness and safety of 5 mg olanzapine (OLZ) in preventing vomiting and nausea caused by carboplatin chemotherapy. Methods: All patients with malignant tumors (n = 113) who underwent Carboplatin (AUC ≥ 5) treatment were randomly categorized into two groups: the standard group (n = 57) and the OLZ regimen (n = 56). The major endpoints of the trial were the TC (total control) between two groups during the OP (Overall phase, 0-120 hours), DP (delayed phase, 25-120 hours), and AP (acute phase, 0-24 hours). The secondary endpoints were the CR (complete response) and TP (total protection) during AP, OP, and DP. The time of first vomiting was compared between the two groups using Kaplan-Meier curves. The impact of CINV on the quality of life was assessed by the Functional Living Index-Emesis (FLIE). OLZ-related side effects were also recorded. Results: (1) The primary endpoint TC rates were more favorable in the OLZ regimen group than in the standard group during the AP 87.50% (49/56) vs. 63.15% (36/57) P = 0.003, OP 62.50% (35/56) vs. 31.57% (18/57) P = 0.001, and DP 64.28% (36/56) vs. 33.33% (19/57) P = 0.001. (2) The secondary endpoints TP were 82.14% (46/56) vs. 63.15% (36/57), P = 0.024, 83.92% (47/56) vs. 63.15% (36/57). P = 0.012 during the DP and OP. There was no statistical significance during AP between the two groups. The CR rates were not statistically different between the two groups during the three periods, P > 0.05; (3) The first vomiting time in the OLZ group was delayed compared with the standard group (P = 0.248). The effect on life quality (score ≥ 108) assessed by FLIE was 62.50% vs. 43.48% between the two groups, P < 0.05. The primary side effects of OLZ are fatigue (85%) and somnolence (75%). The primary side effects of the standard group are fatigue (77%) and loss of appetite (85%). Conclusion: The 5 mg OLZ-based triple antiemetic regimen is effective and safe in preventing vomiting and nausea induced by Carboplatin.