This is a multicenter phase II study designed to evaluate the efficacy and safety of TQB3454 as monotherapy in patients with advanced solid tumors, divided into three cohorts.Cohort 1: Enrolled patients with diffuse glioma harbouring IDH1 R132 mutations. Cohort 2: Enrolled patients with advanced solid tumours (excluding glioma) harbouring IDH1 R132 mutations who failed standard therapy. Cohort 3: Enrolled patients with locally advanced, recurrent and/or metastatic biliary tract cancer without IDH1 mutations who progressed after gemcitabine or fluoropyrimidine-based treatment.