A Clinical Study of BioTTT001 in Combination With Toripalimab and Regorafenib in Patients With Colorectal Cancer

This study includes a dose escalation phase and a dose expansion phase. The dose escalation phase will adopt a 3+3 design. Subjects were first treated with BioTTT001 monotherapy (hepatic artery infusion, administered on D1 and D8 for a total of two doses) after enrollment. If the subject does not develop dose-limiting toxicity (DLT) in the monotherapy stage and is judged to be safe and tolerable by the investigator, the subject will enter the treatment phase of BioTTT001 in combination with toripalimab and regorafenib 2 weeks after the first dose of BioTTT001 ( toripalimab 160mg iv. D1 and D15 , BioTTT001 5×10\^9 viral particle (VP)/5×10\^10 VP/1×10\^11 VP hepatic arterial infusion (HAI.) D2 and D16 , regorafenib 80 mg Po. D1-D21; 4 weeks per cycle). In the dose expansion phase, different dose groups can be expanded, and the total number of enrolled subjects is expected to be 23\~48 for further safety, tolerability, pharmacokinetics and preliminary efficacy evaluation.