Chiu, L., Chow, R., Popovic, M., Navari, R.M., Shumway, N.M., Chiu, N., . . . DeAngelis, C. (2016). Efficacy of olanzapine for the prophylaxis and rescue of chemotherapy-induced nausea and vomiting (CINV): A systematic review and meta-analysis. Supportive Care in Cancer, 24, 2381–2392. 

STUDY PURPOSE: To evaluate the effectiveness of olanzapine compared to other antiemetic regimens for preventative and breakthrough chemotherapy-induced nausea and vomiting (CINV). A secondary objective is to evaluate the effectiveness of 5 mg compared to 10 mg olanzapine for the prevention of CINV.

TYPE OF STUDY: Meta-analysis and systematic review

• FINAL NUMBER STUDIES INCLUDED = 13 total studies, 10 for prevention and 3 for breakthrough CINV
• TOTAL PATIENTS INCLUDED IN REVIEW = 1,082 patients for prevention and 308 patients for breakthrough
• SAMPLE RANGE ACROSS STUDIES: Prevention studies: 19–241 patients; breakthrough studies: 106–109 patients
• KEY SAMPLE CHARACTERISTICS: Prevention studies: Six studies included patients with HEC, four with both HEC and MEC, and no studies with only MEC. Breakthrough studies: Two studies included patients with MEC, and one study included HEC.

PHASE OF CARE: Active antitumor treatment
 
APPLICATIONS: Elder care

Efficacy of Acute Phase: Olanzapine was statistically superior to non-olanzapine regimens for emesis (RR = 1.10, 95% CI [1.03, 1.17]) but not nausea. The 10 mg olanzapine was statistically superior to a non-olanzapine regimen for emesis and nausea.

Efficacy of Delayed Phase: Olanzapine was statistically superior to standard antiemetic regimens for emesis (RR = 1.31, 95% CI [1.14, 1.52]) and for nausea (RR = 1.50, 95% CI [1.15, 1.97]). The 10 mg olanzapine was statistically superior to a non-olanzapine regimen for emesis (RR = 1.31, 95% CI [1.11, 1.54]) and nausea (RR = 1.50, 95% CI [1.15, 1.97]).

Efficacy Overall: Olanzapine was statistically superior to standard anti-emetic regimens for emesis (RR = 1.41, 95% CI [1.18, 1.68]) and for nausea (RR 1.53, 95% CI [1.18, 1.97]). Olanzapine 5 mg and 10 mg were both statistically superior for emesis, and 10 mg strength was superior for nausea. No studies were available for nausea with 5 mg.

Efficacy of Breakthrough: Only emesis (not nausea) was available for analysis, and olanzapine showed superiority (RR = 2.09, 95% CI [1.63, 2.68]) to non-olanzapine regimens.

Olanzapine is effective in treating emesis at all time points and is effective in treating nausea in the delayed phase. More studies are needed to determine the most effective dosing.

• Limited number of studies included
• Low sample sizes
• A secondary objective was to evaluate the effectiveness of 5 mg compared to 10 mg, but no results were found to answer this objective (5 mg and 10 mg were compared only to non-olanzapine regimens).

Olanzapine should be used as an adjunct medication for the treatment of acute chemotherapy related vomiting, breakthrough vomiting, and delayed CINV.