NCT07162714

SCRT Followed by AK112 in pMMR/MSS Mid-low Rectal Cancer

Short-Course Radiotherapy Followed by Ivonescimab (AK112) in pMMR/MSS Mid-Low Rectal Cancer: An Exploratory Phase II Clinical Study.

• Status: Not Yet Recruiting
• Phase: Phase 2
• Study type: Interventional
• Enrollment: 30 (estimated)
• Sponsor: Zhejiang Cancer Hospital · Academic / Other
• Sex: All
• Age: 18 Years – 75 Years
• Healthy volunteers: Not accepted

Summary

Primary Objectives： Evaluate the complete response rate (CR rate) and safety of short - course radiotherapy combined with ivonesimab (AK112) in patients with pMMR/MSS mid - low rectal cancer. Secondary Objectives： Evaluate treatment - related toxic reactions, the quality of life, long - term prognosis (local control \[LC\], disease - free survival \[DFS\] and overall survival \[OS\]). Patients will : Receive Radiotherapy: Pelvic IMRT or VMAT, DT 25Gy/5Fx. One week after radiotherapy, begin treatment with Ivorsimab (AK112) at a dose of 20mg/kg by intravenous drip on day 1. One cycle is 21 days, and a total of 6 cycles are to be carried out. Evaluate the curative effect after 3 cycles of treatment. Patients with progressive disease (PD) will withdraw from the study, and other treatment plans will be adjusted in a timely manner. Patients with CR/PR/SD will continue treatment for another 3 cycles. Conduct a comprehensive assessment after 6 cycles of treatment. Patients who achieve cCR can choose the watch - and - wait approach. For patients who do not achieve cCR, TME surgery is recommended. Decide whether to perform adjuvant chemotherapy based on the postoperative pathological findings.

Conditions

• Rectal Cancer
• Radiation
• AK112

Interventions

Type	Name	Description
RADIATION	radiotherapy	The patients receive pelvic radiotherapy: Intensity-Modulated Radiation Therapy (IMRT) or Volumetric Modulated Arc Therapy (VMAT), with a total dose of 25 Gy delivered in 5 fractions. Radiotherapy is to start on day 1 and to finish on day 5.
DRUG	Ivonescimab (20mg/kg Q3W)	The first dose of vonescimab (AK112) was administered 1 week after the completion of radiotherapy. Ivonescimab (AK112) was initiated at a dose of 20 mg/kg via intravenous infusion on Day 1 of each 21-day cycle, for a total of 6 cycles.
OTHER	Non-operative Management	Subjects who achieve cCR after radiation and 6 cycles treatment of Ivonescimab can, after discussion with the local investigator, decline surgery and opt for a non-operative management.
PROCEDURE	Surgery	For patients who do not achieve cCR at the end of 6 cycles treatment of Ivonescimab, TME surgery is recommended.

Timeline

• Start date: 2025-09-01
• Primary completion: 2026-06-30
• Completion: 2028-12-31
• First posted: 2025-09-09
• Last updated: 2025-09-09