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.