Effectiveness of olanzapine in patients who fail therapy with aprepitant while receiving highly emetogenic chemotherapy.

Chemotherapy-induced nausea-vomiting (CINV) compromises the quality of life of patients with cancer. We present data on the effectiveness of olanzapine after failure of aprepitant in patients receiving highly emetogenic chemotherapy (HEC). A single-center prospective study was conducted, where patients ≥ 18 years who failed aprepitant, palonosetron, dexamethasone (APD) received olanzapine, palonosetron and dexamethasone (OPD) in the subsequent cycle of HEC. Failure of APD was defined as occurrence of ≥ grade 2 acute and/or delayed nausea ± vomiting. Response rates were compared with what was achieved in their previous cycle with the use of APD in the acute (0-24 h), delayed (24-120 h) and overall (0-120 h) periods after the start of HEC. Impact on life was assessed using the MD Anderson Symptom Inventory (MDASI). Fifty-five patients failed APD and received OPD in the subsequent cycle; 54 were evaluable for response. Complete response rate for OPD versus APD is 80 versus 20% (acute period), 90 versus 18% (delayed period) and 74 versus 5% (overall period), and no nausea rate for OPD versus APD is 57 versus 13% (acute), 59 versus 15% (delayed) and 48 versus 0% (overall period), p < 0.001 for all comparisons. MDASI scores showed significant improvement after switching to OPD. A mild increase in drowsiness noted in patients receiving OPD did not affect daily life in most patients. In patients receiving HEC and failing CINV prophylaxis with APD, switching to OPD regimen in the subsequent cycle greatly improves control of vomiting, increases "no nausea" rates and significantly reduces symptom severity scores.