Wuhan Binhui Biotechnology Co., Ltd. Biological Innovation Park Branch

1. Evaluate the delayed adverse reactions and long-term safety of subjects who have received at least one OH2 injection 2. Evaluate the long-term efficacy of subjects who have received OH2 injection over time 3. Evaluate the quality of life of subjects who have received OH2 injection (EORTC QLQ-C30 (version 3))

To evaluate the effectiveness of intratumoral OH2 injection combined with investigator-selected chemotherapy (with or without the option of adding immunotherapy) in subjects with unresectable advanced or metastatic biliary tract cancer who have failed at least one line of standard therapy.

The main purpose of this additional Phase II case expansion phase is to evaluate the anti-tumor efficacy of OH2 injection.