Short-Course Radiotherapy With CAPOX and Bevacizumab, With or Without PD-1 Inhibitor, for Treating Locally Advanced Rectal Cancer

What this Trial Is About

Researchers are evaluating the effectiveness and safety of combining short-course radiotherapy with CAPOX chemotherapy plus bevacizumab, with or without a PD-1 inhibitor, in patients who have locally advanced rectal cancer LARC. The study aims to see if adding immunotherapy improves the complete response rate, improves local control, and reduces the chance of cancer spreading. This phase 2 trial compares sequential chemoradiotherapy and targeted therapy with or without immunotherapy to find the best approach for total neoadjuvant therapy in this condition. Participants will receive short-course radiotherapy 25 Gy over 5 fractions, followed by four cycles of the CAPOX regimen, which includes oxaliplatin given intravenously at 130 mgm and capecitabine taken orally at 1000 mgm for 14 days every three weeks. Bevacizumab is also given intravenously at 7.5 mgkg on day 1 every three weeks. In one group, patients will also receive a PD-1 inhibitor, toripalimab, given intravenously at 240 mg on day 1 every three weeks. After completing the total neoadjuvant therapy, doctors will decide whether to use a watch-and-wait approach or perform surgery based on tumor response, and whether to give additional chemotherapy after surgery will depend on pathology results. Throughout the study, participants will be closely monitored with imaging and clinical assessments to evaluate tumor response and side effects. The main outcome measured is the complete response rate two weeks after surgery. Researchers will also follow participants for up to 48 months to assess disease-free survival, distant metastasis, local recurrence, overall survival, pathological stage, tumor regression grade, and sphincter preservation rate. The study lasts several years to capture long-term outcomes and safety data.

SCRT Followed by CAPOX + Bev ± PD-1 Inhibitor for TNT in LARC