Abstract: Objective To explore the incidence and characteristics of adverse drug reactions (ADR) related to tislelizumab injection. Methods ADR reports submitted by medical institutions to the national ADR monitoring system database in 2024 were collected, involving the basic information of patients, use of drugs, organs and systems involved, and manifestations. Charts were used to analyze the characteristics of ADR. Results In the 447 reports, 348 men (77.85%) and 99 women (22.15%) were involved. The mean age was (57.00±15.56) years. Most of the patients were above 50. The drug cycle of ADR ranged from 0 to 483 days. ADR were the most frequent in the first cycle (1 to 21 days) of treatment (89.71%). The ADR involved multiple systems-organs. There were 228 cases that involved the blood system (44.79%) and 2 cases of sequelae (0.45%). The clinical manifestations were all hypothyroidism. There were 270 cases (60.40%) of severe ADR of G3 and 4 cases of severe ADR of G4 (0.90%). All these ADR occurred after cycle 1 medication, but patients improved after treatment. Most of these ADR were mitigated (80.31%). Conclusion Tislelizumab injection is mostly used for treating a wide range of tumors. The related ADR involve multiple systems and organs, and some severe ADR are potentially life-threatening. Rational clinical use of this drug is recommended. Monitoring is required. Early detection and interventions are critical to management of ADR.

Key words: Immune Checkpoint Inhibitors, Tislelizumab Injection, Blood System, Skin System, Gastrointestinal System, Hypothyroidism, Adverse Drug Reactions