Olanzapine May Prevent Nausea and Vomiting During Moderately Emetogenic Chemotherapy

Olanzapine May Prevent Nausea and Vomiting During Moderately Emetogenic Chemotherapy

Adding 10 mg of olanzapine to aprepitant, palonosetron, and dexamethasone improved complete response rates and aided in the prevention of nausea and vomiting in adults receiving moderately emetogenic chemotherapy, according to study findings published in JAMA Network Open.

“These findings suggest that this [olanzapine] regimen could be considered as one of the standards of antiemetic therapy in patients receiving oxaliplatin-, irinotecan-, or carboplatin-based chemotherapy,” the study authors wrote.

Patients assigned the olanzapine-based regimen had a higher CR rate (n = 248; 91%) compared with those assigned observation (n = 222; 82%) during a 120-hour treatment period (P = .005).

There were also significant differences with regards to nausea control between both groups. Patients assigned the olanzapine-based regimen, compared those assigned observation, had greater nausea control (96% vs 87%; P < .001) and chemotherapy-induced nausea and vomiting control (96% vs 91%; P = .02) during this assessment period.

CR rates also varied with the type of chemotherapy. CR with the olanzapine-based regimen occurred in more patients receiving oxaliplatin-based (OR = 0.36, 95% CI, 0.16-0.85) and carboplatin-based therapies (OR, 0.23; 95% CI, 0.07-0.73), but not with the irinotecan-based therapy (OR, 2.36; 95% CI, 0.23-24.25).

More patients in the observation group received rescue medications compared with the olanzapine group (11% vs 4%; P = .001) during the overall assessment period.

Grade 1 somnolence occurred in 27 patients (10%) after chemotherapy and olanzapine vs no patients in the observation group. Researchers noted that no other adverse events were deemed related to olanzapine.

Notably, 515 patients in the study were able to have risk stratification calculated per the chemotherapy-induced nausea and vomiting risk score. Overall, there were no significant differences between low-risk and high-risk groups for chemotherapy-induced nausea and vomiting control rates (90% vs 88%, respectively; P = .51) and CR rates (88% vs 85%; P = .17)

However, patients in the olanzapine group with a low-risk chemotherapy-induced nausea and vomiting score had significantly increased CR rates compared to the observation group also classified as low-risk (91% vs 84%; P = .03). This was also observed regarding chemotherapy-induced nausea and vomiting control rates (94% vs 84%; P = .002).

Researchers also measured quality of life via a FLIE scale core reduction of more than 10 points from baseline. Reduced quality of life related to chemotherapy-induced nausea and vomiting occurred in more patients in the observation arm vs the olanzapine arm (12% vs 6%; P = .03). When assessed for vomiting, scores were reduced by more than 5 points in 8% of patients in the observation group vs 3% in the olanzapine group (P = .01).

The study consisted of 560 adults with solid malignant tumors who were treated with oxaliplatin-, carboplatin-, or irinotecan-based chemotherapy. Among the patients in the study, 64% were men, and the median age was 51 years (range, 19-80). Patients were randomized in a 1:1 fashion to receive dexamethasone, aprepitant, and palonosetron with olanzapine (experimental group) or without olanzapine (observation group).

In particular, patients in the experimental group received 0.25 mg of palonosetron intravenously on day 1 of chemotherapy, 12 mg of dexamethasone intravenously on day 1, and 125mg of aprepitant orally on day 1 and 80 mg orally on days 2 and 3. Additionally, adults in the experimental arm received 10 mg of olanzapine per day orally once at night on days 1 through 3.

The primary endpoint of this study was CR, which was defined as the proportion of patients with no significant nausea, no vomiting, and no use of rescue medications for nausea. There were also secondary endpoints of this study, which included the proportion of patients receiving rescue medications, experiencing nausea and chemotherapy-induced nausea and vomiting, and experiencing adverse events.

Reference

Ostwal V, Ramaswamy A, Mandavkar S, et al. Olanzapine as Antiemetic Prophylaxis in Moderately Emetogenic Chemotherapy: A Phase 3 Randomized Clinical Trial. JAMA Netw Open. 2024;7(8):e2426076. Published 2024 Aug 1. doi:10.1001/jamanetworkopen.2024.26076