Olanzapine as antiemetic drug in oncology: a retrospective study in non-responders to standard antiemetic therapy

Background The role of olanzapine in the treatment of chemotherapy-induced nausea and vomiting (CINV) in addition to the antiemetic therapeutic combination with aprepitant, setrons, and corticosteroids has not been well defined. Objective To investigate the effectiveness of the addition of olanzapine to a standard triplet therapy for the prevention of CINV in patients who experienced CINV during their first chemotherapy course, despite receiving a well-managed prevention protocol. Setting One comprehensive cancer centre in France. Method In a retrospective study with comparator, patients with a high risk of emesis were assigned to two groups during two different 6-month periods, before and after the introduction of olanzapine in clinical practice, respectively. In the olanzapine group, the antiemetic protocol for the second course of chemotherapy was reinforced by the addition of olanzapine at 5 mg/day from day 1 to 5 in contrast with the control group. Main outcome measure The proportion of patients who experienced neither nausea nor emesis during the delayed phase (24–120 h). Results The 25 patients in each group exhibited comparable characteristics and emetic chemotherapy level. During the first course, no significant difference was observed. During the second course, nausea and vomiting were ameliorated in 12 patients in the olanzapine group and 4 patients in the control group (p < 0.05). Nausea (12 vs. 4, p < 0.05) and vomiting (18 vs. 11, p < 0.05) also significantly improved. In the OLZ group, no adverse event was linked to olanzapine use. Conclusion The addition of olanzapine was observed to effectively restore CINV prevention in patients who did not respond to standard antiemetic therapy.