The Safety and Efficacy of Ondansetron in Reducing Immune Checkpoint Inhibitor-Related Toxicities

Inclusion Criteria: 1. Age: 18 to 80 years old, both male and female are acceptable. 2. The imaging or pathological diagnosis is hepatocellular carcinoma; 3. It is planned to carry out standard treatment for liver cancer, specifically including lenvatinib + tislelizumab or lenvatinib + pembrolizumab or atezolizumab + bevacizumab. 4. ECOG score: 0 to 2 points; 5. Expected survival period ≥12 weeks; 6. Baseline blood cell count tests and blood biochemistry must meet the following standards: White blood cell count ≥3.0×10\^9/L; Hemoglobin ≥90 g/L; The absolute neutrophil count is ≥1.5×10\^9/L; Platelet count ≥100×10\^9/L; Alanine aminotransferase (ALT), aspartate aminotransferase (AST) ≤ 2.5 times the upper limit of normal (ULN). Total bilirubin ≤ twice ULN; Serum creatinine ≤ 1.5 times ULN; Albumin ≥30 g/L; 7. The subjects voluntarily joined this study, signed the informed consent form, had good compliance and cooperated with the follow-up. Exclusion Criteria: 1. Those who have received treatment with ondansetron within 14 days; 2. Patients with autoimmune diseases; 3. Use of systemic glucocorticoids or other immunosuppressants within 14 days; 4. Those who have previously discontinued ICI treatment due to irAEs; 5. Those with severe liver dysfunction (Child-Pugh grade C); 6. Those with contraindications to ondansetron such as serotonin syndrome or phenylketonuria; 7. Patients allergic to ondansetron; 8. Those who are currently using drugs that may have serious interactions with ondansetron, such as apopmorphine; 9. The researcher evaluated that the patient was unable or unwilling to comply with the requirements of the research protocol.