A recent study has highlighted the effectiveness of olanzapine in managing nausea among patients undergoing treatment with trastuzumab deruxtecan (T-DXd) for HER2-positive and HER2-low metastatic breast cancer. The findings, stemming from the ERICA study, suggest that incorporating olanzapine into standard antiemetic regimens can significantly improve patient outcomes.
ERICA Study: Olanzapine for Nausea Management
The ERICA study, a placebo-controlled, double-blind, randomized phase II trial, was conducted across 43 hospitals in Japan between November 2021 and September 2023. The study enrolled adult patients with HER2-positive or HER2-low metastatic breast cancer initiating their first cycle of T-DXd. Participants were randomized 1:1 to receive either olanzapine (5 mg daily) or placebo from days 1 to 6, alongside a 5-HT3 receptor antagonist (5-HT3RA) and dexamethasone on day 1. The primary endpoint was the complete response (CR) rate during the delayed phase (days 1-5 post-T-DXd), defined as no emetic episodes and no use of rescue medication.
Key Findings
The results indicated a significantly higher complete response rate during the delayed phase in the olanzapine group (70.0%) compared to the placebo group (56.1%), with a difference of 13.9% (one-sided P = 0.047). Similarly, CR rates in the persistent phase (days 2-6 after treatment) were higher in the olanzapine group (63.9%) compared to the placebo group (44.4%). Acute phase CR rates were comparable between the two groups (92.5% vs. 92.7%).
According to the study, "Continuous greater efficacy of olanzapine over placebo was observed throughout the 21-day observation period."
Safety Profile
While somnolence was more frequent in the olanzapine group (25.0%) compared to the placebo group (10.8%), no severe cases were reported. Hyperglycemia was noted in 7.5% of the olanzapine group. Overall, the study indicated a favorable safety profile for olanzapine in this context.
Implications for Oncology Nursing
Oncology nurses are at the forefront of managing treatment-related side effects, including nausea. Patients may be hesitant to take olanzapine due to its associations with other conditions like schizophrenia. Therefore, nurses play a vital role in educating patients about the specific benefits of olanzapine, especially when used with 5-HT3 receptor antagonists and dexamethasone, in managing nausea induced by T-DXd. Close monitoring for potential side effects, such as somnolence, is also essential.
Improving Patient Outcomes
Effective management of nausea is crucial for ensuring treatment adherence and enhancing the quality of life for patients undergoing T-DXd therapy. The ERICA study underscores the value of olanzapine in reducing delayed and persistent nausea when combined with standard antiemetic therapy. By implementing clear protocols and providing comprehensive patient education, oncology nurses can optimize symptom management, minimize treatment interruptions, and foster a supportive environment for patients battling breast cancer.
