Navari, R.M., Einhorn, L.H., Loehrer, P.J., Sr., Passik, S.D., Vinson, J., McClean, J., … Johnson, C.S. (2007). A phase II trial of olanzapine, dexamethasone, and palonosetron for the prevention of chemotherapy-induced nausea and vomiting: a Hoosier oncology group study. Supportive Care in Cancer, 15, 1285-1291.

To examine the effectiveness of olanzapine in the treatment of chemotherapy-induced nausea and vomiting without the use of dexamethasone after day 1

A 10-mg oral dose of olanzapine was given every day, four times a day for prevention (rather than breakthrough) nausea and vomiting. On day 1 of chemotherapy, patients received 0.25 mg IV palonosetron and dexamethasone (8 mg for moderately emetogenic chemotherapy [MEC], 20 mg for highly emetogenic chemotherapy [HEC]) as well as 10 mg oral olanzapine. On days 2-4, patients received only 10 mg olanzapine daily. The same antiemetic regimen was continued for as many cycles as the patient completed (1-6 cycles). Patients received no other antiemetics on days 2-4. Patients were permitted to take rescue therapy.

The sample consisted of 40 patients who were chemotherapy-naive and receiving HEC or MEC.

This was a prospective, nonrandomized trial with no control or comparison group, consisting of descriptive analysis only (percentage of patients with response described).

• The M.D. Anderson Symptom Inventory (MDASI) was used.
• Patients recorded daily episodes of vomiting and retching.

Complete response (CR), defined as no emesis and no rescue medications administered and no nausea, was found in 100% of HEC patients and 97% of MEC patients in the acute period (0-24 hours after chemotherapy).

Responses for the delayed period (24-120 hours) decreased. Seventy-five percent of patients reported CR in the delayed and overall periods for emesis and even fewer for control of nausea (50% of HEC patients with CR for nausea and 78% of MEC patients with CR for nausea in the delayed and overall periods). No adverse events to study drugs were noted (no grade 3 or 4 toxicities). Olanzapine was not associated with sedation, weight gain, or hyperglycemia.

• The sample size was small.
• Investigators stated that combination olanzapine, dexamethasone, and palonosetron was effective in controlling acute and delayed CINV in patients receiving both HEC and MEC; however, no control or comparison group was included in the study.
• The investigators stated that the results indicated effectiveness compared to studies using triple-drug regimens; however, no head-to head comparison was done in this study. This is especially problematic given that aprepitant was not used and is now recommended per guidelines.
• Half of the patients in the HEC group still experienced nausea in the delayed and overall study periods (0-120 hours after chemotherapy). In the MEC group, 22% of patients still experienced nausea in the delayed and overall periods.
• Use of rescue medications was not described, although these were allowed and patients were permitted to continue in the study even if rescue medications were used.