Sevacizumab

This study is a prospective, single-arm clinical trial with a dose-reduction design, which is expected to enrol 18 patients with locally advanced rectal cancer with pMMR status. The aim is to investigate the safety and efficacy of neoadjuvant chemoradiotherapy combined with sintilimab and suvecitib.
Patients will receive long-course chemoradiotherapy (concurrent capecitabine, 1000 mg/m², twice daily, days 1-14, Q3W, 2 cycles; sintilimab, 200 mg, d1, IV drip, Q3W, 2 cycles), followed by 6 cycles of the Capeox regimen in combination with sintilimab and suvecitib, namely oxaliplatin 130 mg/m², d1, IV infusion, every 3 weeks; and capecitabine 1,000 mg/m², twice daily, days 1-14, every 3 weeks; sintilimab, 200 mg, Day 1, IV drip, every 3 weeks; suvectitumab (anti-angiogenic agent), 2.0/1.5/1.0 mg/kg, Day 1, IV drip, every 3 weeks. A total of 8 cycles of sintilimab and 6 cycles of suvectitumab were administered during the neoadjuvant treatment period.
If, following completion of neoadjuvant therapy, the subject has not achieved cCR/near-cCR status, TME surgery or other therapeutic surgery shall be performed; the interval between the final dose of suvectitumab and surgery should be ≥6 weeks. If cCR/near-cCR status is achieved, watchful waiting or other treatment options shall be discussed with the patient. The adjuvant treatment regimen following surgery shall be determined by the investigator based on the patient's pathological results.