Olanzapine Significantly Reduces CINV in Patients Receiving MEC

Olanzapine Significantly Reduces CINV in Patients Receiving MEC

Olanzapine, combined with a 5 HT3 antagonist, dexamethasone, and an NK1 receptor antagonist, improved the rate of complete response in patients receiving moderately emetogenic chemotherapy regimens, according to findings from the Indian, phase 3 OMEC study that were presented during the 2023 European Society of Medical Oncology Congress.

In this trial, a complete response was defined as no vomiting and no significant nausea. Secondary end points from the study suggest that olanzapine can successfully prevent nausea—leading to a decrease of rescue medications. Olanzapine itself was found to be well-tolerated, with no intervention-related adverse events, according to investigators.

As Vikas Ostwal, MD, DM, explained in the presentation, chemotherapy-induced nausea and vomiting (CINV) is one of the most feared treatment-related complications that patients express concerns about. Therefore, finding ways to eliminate it is a key strategy in helping patients face their treatment.

“As the aim of antiemetic prophylaxis should be complete, or nearly complete, absence of CINV, the combination of olanzapine, a 5 HT3 antagonist, dexamethasone, and an NK1 receptor antagonist, shows the way forward in terms of achieving high CR rates,” Ostwal, who is an associate professor at the department of medical oncology at Tata Memorial Hospital, said in a presentation of the findings. “[It] should be considered as a standard of care for moderately emetogenic chemotherapy regimens.”

Key Findings

A total of 282 patients were randomly assigned to olanzapine and 278 patients were randomized to the control arm. The proportion of patients with no vomiting or significant nausea was higher in the olanzapine group in the 120 hours following chemotherapy (92% vs 86%; P = .005).

In the 25–120-hour timeslot following chemotherapy, the rate of patients who completely responded to their antiemetic regimen was higher with olanzapine as well (95% vs 86; P < .001).

In addition, in the 120 hours following chemotherapy, the proportion of patients with no sign of nausea was higher in the olanzapine group (96% vs 87%; P < .001). The change was also statistically significant in the 25-120 hours following chemotherapy (97% vs 86%; P < .001).

Of note, the difference between the experimental and control groups was not statistically significant in the first 24 hours following chemotherapy.

Methodology

This study included patients who were at least 18 years or older, chemotherapy naïve, and with adequate end-organ function. They also needed an ECOG performance status that was less than 1.

Patients received regimens at 100% doses. Oxaliplatin-containing regimens (61%), carboplatin-containing regimens (29%), and irinotecan-containing regimens (10%) were all included. Patients could not participate if they had previously experienced emesis or if they experienced clinically significant nausea in the 24 hours preceding the first study dose.

On Day 1, patients took their antiemetic medication 60 minutes prior to chemotherapy. For the control arm, this included 125 mg of aprepitant, 0.25 mg of intravenous (IV) palonosetron, and 12 mg of IV dexamethasone. The experimental cohort received this same regimen, with the addition of 10 mg of oral olanzapine at bedtime.

On days 2 and 3, participants took their prescribed regimens in the morning. The control and experimental groups received aprepitant at 80 mg and aprepitant 8 mg plus 10 mg of olanzapine at night, respectively.

Reference

Ostwal VS, Mandakvar S, Parulekar M, et al. Olanzapine for the prevention of chemotherapy induced nausea vomiting in patients receiving moderately emetogenic chemotherapeutic (MEC) regimens: Results of a prospective triple blinded phase III multicentric study (OMEC). Ann of Oncol. 2023;34(supple_2): S1254-S1335. 10.1016/annonc/annonc1358