Trial to Evaluate Efficacy of Olanzapine With Short-acting 5HT3 Inhibitors in Chemotherapy-induced Nausea & Vomiting (CINV) Prophylaxis

Inclusion Criteria: 1. High-emetogenic chemotherapy (HEC) regimen (e.g., cisplatin ≥70 mg/m2 or doxorubicin ≥60 mg/m2 or carboplatin AUC≥4). Patients that are prescribed less doses of mentioned agents are still allowed if another high-emetogenic drug will be administered (eg, doxorubicin plus cisplatin); 2. Administration of HEC component only in first day of the cycle; 3. No previous chemotherapy or radiotherapy; 4. No concomitant quinolone antibiotics administration; 5. ECOG PS ≤2; 6. No nausea and vomiting 24 hours before enrollment; 7. Adequate hepatic and renal function (eg, ALaT, ASaT ≤3 ULN, creatinine clearance ≥50 ml/minute). 8. No brain metastases, leptomeningeal carcinomatosis, and chronic diseases such as uncontrolled diabetes mellitus and chronic alcohol consumption. 9. Subject willing to participate in the trial and provided informed consent form. Exclusion Criteria: 1. Previous chemotherapy or radiotherapy; 2. Moderate- or low- emetogenic chemotherapy; 3. Multiday administration of HEC agents; 4. ECOG PS \>2; 5. History of brain metastases, signs of symptoms of bowel obstruction; 6. Nausea and/or vomiting of any genesis 24 hours before enrollment; 7. Uncontrolled diabetes mellitus or other metabolic diseases; chronic alcohol consumption. 8. Diseases and conditions interfere with subject ability to swallow the drug and to take oral medication; 9. Concomitant therapy with olanzapine or other antipsychotic drugs; history of mental illness; 10. Concomitant therapy with quinolone antibiotics; 11. Contraindications for olanzapine or aprepitant administration; 12. Intraperitoneal or intrapleural administration of HEC drugs; 13. Inadequate hepatic and/or renal function.