Recombinant oncolytic adenovirus injection (KD01) is an oncolytic virus product. Its main component is a conditionally replicative recombinant human type 5 adenovirus, where part of the E3 region has been replaced with the gene encoding the tBid apoptotic protein.AK104 is a humanized bispecific antibody co-targeting PD-1 (Programmed Cell Death Protein 1) and CTLA-4 (Cytotoxic T-Lymphocyte-Associated Antigen 4)-two key immune checkpoint receptors. It is designed as a novel tetrameric construct that preferentially binds to tumor-infiltrating lymphocytes (TILs) co-expressing PD-1 and CTLA-4 in the tumor microenvironment (with higher avidity than in peripheral tissues).This is a Phase I clinical study designed to evaluate the safety, tolerability, and preliminary efficacy of intravesical instillation of recombinant oncolytic adenovirus injection (KD01) in patients with bladder cancer.This study consists of Phase Ia and Phase Ib, where Phase Ia is a dose-escalation stage.The Phase Ia will include histopathologically confirmed non-muscle-invasive bladder cancer (NMIBC) patients with high-risk stratification (including extremely high-risk).The Phase Ib study will include two independent cohorts: Cohort A comprises high-risk non-muscle-invasive bladder cancer (NMIBC) patients (carcinoma in situ \[CIS\], with or without Ta/T1 stage lesions) who have shown no response to BCG. Cohort B will include T2-4aN0-1M0 stage bladder cancer patients (clinically localized muscle-invasive bladder urothelial carcinoma).