QL1706 Plus XELOX as Neoadjuvant Therapy for MSS/pMMR Clinical Stage III Colon Cancer

A Single-Arm, Exploratory Study of Iparomlimab and Tuvonralimab (QL1706) Plus XELOX as Neoadjuvant Therapy in Patients With Microsatellite Stable (pMMR/MSS) Resectable Stage III Colon Cancer

This is a single-arm, exploratory study enrolling participants with resectable stage III pMMR/MSS colon cancer. Eligible participants who provide written informed consent will receive four cycles of neoadjuvant treatment with iparomlimab and tuvonralimab (QL1706) plus XELOX regimen administered every three weeks (Q3W), followed by radical surgery within two weeks after the last neoadjuvant treatment. After surgery, participants will enter the follow-up phase, or clinicians may decide to administer four additional cycles of adjuvant XELOX chemotherapy based on postoperative pathological findings. The primary endpoint of this study is the pathological complete response (pCR) rate as assessed by investigators. Other endpoints include pathological response (PR), major pathological response (MPR), clinical complete response (cCR), event-free survival (EFS), overall survival (OS), and safety.

Inclusion Criteria:

• Age between 18 and 75 years.
• Histologically or clinically confirmed initially resectable Stage III colon cancer according to the AJCC 8th edition.
• ECOG performance status of 0 or 1.
• pMMR/MSS status confirmed by a local testing center.
• No planned neoadjuvant radiotherapy.
• Participants must voluntarily participate in the study, sign an informed consent form, and demonstrate good compliance.
• Adequate organ function.

Exclusion Criteria:

• Stage IV colon cancer.
• Prior treatment with immune checkpoint inhibitors targeting CTLA-4, PD-1, or PD-L1.
• Current participation in another clinical trial and receiving investigational drugs.
• History of or contraindication to severe allergic reactions to immunotherapy.
• Pregnancy or lactation.
• Active infection requiring treatment.
• Use of immunosuppressive medications.
• Active cardiovascular disease, including stroke or myocardial infarction within 6 months before enrollment, unstable angina, congestive heart failure, or severe uncontrolled arrhythmia requiring medication that may preclude surgery.
• Patients with acute conditions such as obstruction, hemorrhage, or perforation that require immediate surgery.
• Any other condition deemed by the investigator to render the participant unsuitable for the clinical study.