Chow, R., Chiu, L., Navari, R., Passik, S., Chiu, N., Popovic, M., . . . DeAngelis, C. (2015). Efficacy and safety of olanzapine for the prophylaxis of chemotherapy-induced nausea and vomiting (CINV) as reported in phase I and II studies: A systematic review. Supportive Care in Cancer, 24, 1001–1008. 

STUDY PURPOSE: To summarize evidence from phase I and II trials in which olanzapine was used for the prophylaxis of chemotherapy-induced nausea and vomiting (CINV)

• FINAL NUMBER STUDIES INCLUDED = 7 
• TOTAL PATIENTS INCLUDED IN REVIEW = 201
• SAMPLE RANGE ACROSS STUDIES: 3–40 patients
• KEY SAMPLE CHARACTERISTICS: Multiple tumor types across studies; highly and moderately emetogenic chemotherapy regimens

PHASE OF CARE: Active antitumor treatment

The rate of complete control (no emesis, no rescue medication, and no significant nausea) was only identified in one study. Complete response rates were reported in three studies, and they ranged from 75%–100% in the acute phase and 72%–92.5% in the overall phase. In four trials, olanzapine was used as an adjunct with other antiemetics. One study was a retrospective chart review.

The findings of this study suggest that olanzapine can be beneficial in preventing CINV.

• The sample sizes of the studies were small.
• No information was provided regarding the use of any other antiemetics. 
• How a study using a retrospective chart review constitutes as a phase I or II study for inclusion was unclear.

The potential role of olanzapine in the prevention and management of CINV is unclear. This review provides limited evidence of the effects of olanzapine for CINV. Future studies need to compare olanzapine as an adjuvant to recommended antiemetics or olanzapine as a single agent compared to regimens with clear efficacy for the prevention of CINV.