Increasing Olanzapine Prescribing for Patients Undergoing Highly Emetogenic Chemotherapy.

Importance: Olanzapine as part of a 4-drug antiemetic regimen is highly effective at preventing nausea and vomiting in patients receiving highly emetogenic chemotherapy (HEC). National prescribing rates of olanzapine in eligible patients have, however, remained persistently low. Objective: To describe efforts to increase the guideline-concordant use of olanzapine in patients receiving HEC in a statewide oncology collaborative. Design, Setting, and Participants: The Michigan Oncology Quality Consortium (MOQC) is a collaborative of Michigan-based oncology practices whose mission is to advance the care of patients with cancer and their caregivers through comprehensive, patient- and practice-led quality improvement initiatives. Participants were patients receiving HEC at 38 MOQC member practices during an initiative from 2019 to 2023 to improve guideline-concordant inclusion of olanzapine as part of a 4-drug antiemetic regimen in HEC prophylaxis. Interventions: Interventions included performance audit and feedback to practices along with peer comparison, learning collaboratives of practices, education by experts at collaborative meetings, creation of patient-facing materials, and the addition of value-based reimbursement beginning in 2021. Measure performance was assessed using the American Society of Clinical Oncology's Quality Oncology Practice Initiative. Main Outcomes and Measures: Proportion of patients receiving olanzapine for the first cycle of HEC as part of a 4-drug antiemetic regimen for chemotherapy-induced nausea and vomiting. Results: Between 2019 and 2024, data were manually collected from the medical records of 8662 patients treated with HEC at 38 medical oncology practices at 71 sites across the state. Individual patient-level demographic data are not available from the QOPI database. For patients from years 2021 through 2024, the median (IQR) age was 62 (52-69) years; 4434 were female (65.5%); 814 were Black or African American (12.0%), 121 were Hispanic or Latino (1.8%), and 5385 were White (79.7%). The use of olanzapine as part of a 4-drug antiemetic increased from 7.2% in 2019 to 63.4% in 2024 (χ21 = 553.61; P < .001). Conclusions and Relevance: In this quality improvement study of olanzapine prescribing in eligible patients, MOQC deployed quality improvement methods to increase the prescribing of olanzapine as part of a 4-drug regimen in patients receiving HEC, well above both the baseline and national levels of prescribing. This work suggests that efforts to improve patient care can be effective across diverse practice types, locations, and sizes in a statewide collaborative. Ongoing efforts include supporting change in those practices with low rates of prescribing and demonstrating the importance of this work for patient outcomes.