Olanzapine 5 mg plus standard antiemetic therapy for the prevention of chemotherapy-induced nausea and vomiting (J-FORCE): a multicentre, randomised, double-blind, placebo-controlled, phase 3 trial.

BACKGROUND: Olanzapine 10 mg added to standard antiemetic therapy including aprepitant, palonosetron, and dexamethasone has been recommended for the prevention of chemotherapy-induced nausea and vomiting. Guidelines suggest that a dose reduction to 5 mg should be considered to prevent sedation. In several phase 2 studies, olanzapine 5 mg has shown equivalent activity to olanzapine 10 mg and a favourable safety profile in relation to somnolence. We evaluated the efficacy of olanzapine 5 mg combined with standard antiemetic therapy for the prevention of chemotherapy-induced nausea and vomiting caused by cisplatin-based chemotherapy. METHODS: This was a randomised, double-blind, placebo-controlled, phase 3 study to evaluate the efficacy of olanzapine 5 mg with triplet-combination antiemetic therapy done in 26 hospitals in Japan. Key inclusion criteria were patients with a malignant tumour (excluding those with a haemopoietic malignancy) who were scheduled to be treated with cisplatin (≥50 mg/m2) for the first time, age between 20 and 75 years, and with Eastern Cooperative Oncology Group performance status of 0-2. Eligible patients were randomly assigned (1:1) to receive either oral olanzapine 5 mg or placebo once daily on days 1-4 combined with aprepitant, palonosetron, and dexamethasone (dosage based on the standard antiemetic therapy against highly emetogenic chemotherapy). Patients were randomly assigned to interventions by use of a web entry system and the minimisation method with a random component, with sex, dose of cisplatin, and age as factors of allocation adjustment. Patients, medical staff, investigators, and individuals handling data were all masked to treatment assignment. The primary endpoint was the proportion of patients who achieved a complete response, defined as absence of vomiting and no use of rescue medications in the delayed phase (24-120 h). All randomly assigned patients who satisfied eligibility criteria received a dose of cisplatin 50 mg/m2 or more, and at least one study treatment, were included in efficacy analysis. All patients who received any treatment in this study were assessed for safety. This study is registered at UMIN Clinical Trials Registry, number UMIN000024676. FINDINGS: Between Feb 9, 2017, and July 13, 2018, 710 patients were enrolled; 356 were randomly assigned to receive olanzapine and 354 were assigned to receive placebo. All eligible patients were observed 120 h after cisplatin initiation. One patient in the olanzapine group and three in the placebo group did not receive treatment and were excluded from all analyses. One patient in the olanzapine group discontinued treatment on day 1 and was excluded from the efficacy analysis. In the delayed phase, the proportion of patients who achieved a complete response was 280 (79% [95% CI 75-83] of 354 patients in the olanzapine group and 231 (66% [61-71] of 351 patients in the placebo group (p<0·0001). One patient had grade 3 constipation and one patient had grade 3 somnolence related to treatment in the olanzapine group. INTERPRETATION: Olanzapine 5 mg combined with aprepitant, palonosetron, and dexamethasone could be a new standard antiemetic therapy for patients undergoing cisplatin-based chemotherapy. FUNDING: Japan Agency for Medical Research and Development.

Efficacy of Olanzapine in Addition to Standard Triplet Antiemetic Therapy for Cisplatin-Based Chemotherapy: A Secondary Analysis of the J-FORCE Randomized Clinical Trial.

Importance: It is unknown whether olanzapine combined with triplet antemetic therapy is effective for all patients undergoing highly emetogenic chemotherapy. A secondary analysis of randomized clinical trials using olanzapine may provide insight into the effectiveness of olanzapine for chemotherapy-induced nausea and vomiting (CINV), including cisplatin. Objective: To examine the add-on effect of olanzapine according to risk factors for CINV. Design, Setting, and Participants: This preplanned secondary analysis evaluated results of the J-FORCE trial, a large double-blind, placebo-controlled phase 3 randomized clinical trial conducted in Japan from February 9, 2017, to July 18, 2018. Participants were enrolled from 26 participating hospitals across Japan and included patients aged 20 to 75 years who had a malignant tumor and were cisplatin-naive. The efficacy analysis population of the J-FORCE trial was analyzed according to allocation adjustment factors (sex [male or female], age [≥55 years or <55 years], and cisplatin dose [≥70 mg/m2 or <70 mg/m2]) and patient-related risk factors (history of motion sickness, drinking habit [defined as alcoholic drinks consumption in excess of occasional drinking], and history of morning sickness during pregnancy). Statistical analysis was performed from February 18 to April 18, 2020. Interventions: Patients were randomized 1:1 to receive 5 mg of olanzapine or placebo combined with standard triplet antiemetic therapy. Main Outcomes and Measures: The primary end point was complete response (CR, defined as no vomiting and no use of rescue medication) in the delayed phase (24-120 hours after cisplatin-based chemotherapy administration). Secondary end points were CR, complete control, and total control in the acute, delayed, and overall phases for 6 CINV risk factors as well as time to treatment failure. The CR point estimates and 95% CIs of the differences between groups were calculated, and a Mantel-Haenszel test was performed. Results: Of the 705 patients (mean [SD] age, 63.0 [9.2] years; 471 males [66.8%]) included in the efficacy analysis population; 581 patients (82.4%) were 55 years or older, and 526 (74.6%) were treated with a cisplatin dose of 70 mg/m2 or more. Risk difference (RD) for a CR in the delayed phase was significantly greater in the olanzapine group than the placebo group in males (RD, 12.6% [95% CI, 5.0%-20.1%]; P = .001); in females (RD, 14.5% [95% CI, 2.2%-26.3%]; P = .02); in those 55 years or older (RD, 11.1% [95% CI, 3.9%-18.2%]; P = .003) or younger than 55 years (RD, 23.6% [95% CI, 7.3%-38.3%]; P = .005); for a cisplatin dose of 70 mg/m2 or more (RD, 13.5% [95% CI, 5.9%-21.0%]; P < .001); for those without a history of motion sickness (RD, 13.9% [95% CI, 6.9%-20.6%]; P < .001); for those with a drinking habit (RD, 14.9% [95% CI, 6.1%-23.4%]; P = .001) or without a drinking habit (RD, 12.0% [95% CI, 2.5%-21.3%]; P = .01); and for those with a history of morning sickness during pregnancy (RD, 27.2% [9.7%-42.6%]; P = .002). In other subgroups, a delayed CR was higher in the olanzapine group than the placebo group, although not significantly higher. Conclusions and Relevance: Results of this study suggest a benefit of using 5 mg of olanzapine plus triplet antiemetic therapy to counter CINV regardless of the presence or absence of risk factors. Trial Registration: University Hospital Medical Information Network Clinical Trials Registry Identifier: UMIN000024676.