QL1706 Injection Plus Bevacizumab and XELOX vs Placebo Plus Bevacizumab and XELOX as First-Line Treatment of Unresectable Metastatic Colorectal Cancer

QL1706 will be administered by IV infusion at 5mg/kg on Day 1 of each 21-day cycle until disease progression (PD), intolerable toxicity, initiation of a new anti-tumor therapy, death, withdrawal of informed consent, loss to follow-up or other conditions requiring termination of the treatment (whichever occurs first). The administration of QL1706 lasts for up to 2 years.

Bevacizumab will be administered by IV infusion at 7.5mg/kg on Day 1 of each 21-day cycle until disease progression (PD), intolerable toxicity, initiation of a new anti-tumor therapy, death, withdrawal of informed consent, loss to follow-up or other conditions requiring termination of the treatment (whichever occurs first). The administration of Bevacizumab lasts for up to 2 years.

Oxaliplatin will be administered by IV infusion at 130 mg/m2 on Day 1 of each 21-day cycle up to 8 treatment cycles.

Capecitabine will be administered orally at 1000 mg/m2 twice daily for 2 consecutive weeks, followed by one-week rest in each 21-day cycle until disease progression (PD), intolerable toxicity, initiation of a new anti-tumor therapy, death, withdrawal of informed consent, loss to follow-up or other conditions requiring termination of the treatment (whichever occurs first). The administration of Capecitabine lasts for up to 2 years.

Placebo will be administered by IV infusion at 5mg/kg on Day 1 of each 21-day cycle until disease progression (PD), intolerable toxicity, initiation of a new anti-tumor therapy, death, withdrawal of informed consent, loss to follow-up or other conditions requiring termination of the treatment (whichever occurs first). The administration of Placebo lasts for up to 2 years.