This study is a Phase II, two-cohort, multicenter, two-stage clinical trial. It plans to enroll 72 subjects with solid tumors who discontinued prior ICI therapy due to irAE. Cohort 1 enrolls subjects with irAE resistant to or dependent on corticosteroid therapy. Subjects in Cohort 1 who achieve ≤ Grade 1 irAE resolution following treatment may then enroll in Cohort 2. Cohort 2 enrolls subjects with irAE achieving ≤ Grade 1 resolution following treatment, and deemed eligible for ICI re-initiation by the investigator. Phase I is the safety run-in phase, enrolling 6 subjects per cohort. Phase II is the expansion phase, enrolling 30 subjects per cohort.
Age ≥ 18 years.
ECOG performance status score 0-1.
Expected survival ≥ 12 weeks.
Solid tumor patients who have discontinued treatment with immune checkpoint inhibitors (ICIs).
1) Individuals with allergic diseases, a history of severe drug allergies, or potential hypersensitivity to Ivarmacitinib or its components; 2) Patients diagnosed with an embolic event within 3 months prior to enrollment, excluding superficial venous thrombosis (e.g., deep vein thrombosis, pulmonary embolism, embolic stroke, myocardial infarction, or peripheral arterial insufficiency); 3) Patients with severe non-irAE-related cardiac, hepatic, renal, or systemic diseases; 4) Patients with active tuberculosis or who received live vaccines during the illness period; 5) Patients with uncontrolled infectious diseases; 6) Patients with moderate to severe heart failure (NYHA Class III/IV); 7) Hepatitis B surface antigen (HBsAg) or hepatitis B core antibody (HBcAb) positive, with hepatitis B virus (HBV) deoxyribonucleic acid (DNA) exceeding 500 IU/mL or 1000 copies per milliliter (cps/mL); Hepatitis C virus (HCV) antibody (HCV-Ab) positive with HCV RNA quantitative levels exceeding the upper limit of normal for the assay; HIV antibody (Anti-HIV) positive; active syphilis. Meeting any one of the above criteria.