Research objective: To compare the efficacy and safety of Capox + Bev versus Capox + Bev combined with primary site radiotherapy + (Iparomlimab and Tuvonralimab) as the first-line treatment for RAS Mutation/pMMR metastatic rectal cancer patients.
Study endpoint:
Primary endpoint: 12-month progression-free survival rate (PFSR)
Secondary endpoints:
* The objective response rate (ORR) and disease control rate (DCR) as determined by the investigator according to the RECIST 1.1 standard, time to response (TTR), duration of response (DOR), progression-free survival (PFS), 6-month progression-free survival rate (PFSR), overall survival (OS);
* The frequency and severity of adverse events (AEs) during treatment (NCI CTCAE 5.0).
This study will enroll 106 patients (stratification factors: presence or absence of liver metastasis; whether NED could be achieved). They were randomly assigned in a 1:1 ratio to:
The treatment group: Capox + Bev combined with primary site radiotherapy and (Iparomlimab and Tuvonralimab), administered every 3 weeks (Q3w), up to a maximum of 8 cycles, followed by a maintenance treatment stage of Capecitabine + Bev + (Iparomlimab and Tuvonralimab), administered every 3 weeks (Q3w).
The control group: Capox + Bev, administered every 3 weeks (Q3w), up to a maximum of 8 cycles, followed by a maintenance treatment stage of Capecitabine + Bev, administered every 3 weeks (Q3w).