A Prospective, Randomized, Controlled Phase II Trial of Regorafenib Alone or in Combination With Hypofractionated/Low-dose Radiotherapy Plus Toripalimab as Third-line Treatment in Patients With Metastatic Colorectal Cancer
The study compares the efficacy and safety of regorafenib alone or in combination with hypofractionated radiotherapy and low-dose radiotherapy (LDRT) plus toripalimab in patients with microsatellite stable metastatic colorectal cancer (MSS mCRC). Patients are randomly assigned (1:1) into the control arm and the experimental arm. Control arm: a total of 54 patients will receive regorafenib monotherapy. Experimental arm: a total of 54 patients will first receive 1 cycle of regorafenib and toripalimab followed by hypofractionated/low-dose radiotherapy. Regorafenib and toripalimab will be continued after the completion of radiotherapy. The survival benefits, response rates, and adverse effects will be analyzed.
• Age ≥18 years old
• An Eastern Cooperative Oncology Group (ECOG) performance status ≤1
• Life expectancy of at least 3 months
• Histopathological confirmed MSS/pMMR adenocarcinoma of the colon or rectum
• At least one evaluable metastatic lesion for radiotherapy according to RECIST 1.1
• Progressed on or after the standard first-and second-line therapies or stopped standard therapy because of unacceptable toxic effects
• Previous radiotherapy completed at least 4 weeks before randomization
• Adequate bone-marrow, hepatic, and renal function: neutrophils ≥ 1.5 × 10\^9/L, Hb ≥ 90 g/L, PLT ≥ 100 × 10\^9/L, ALT/ AST≤2.5 ULN, Cr≤1 ULN
• Sign the informed consent and have good compliance