Nelmastobart（hSTC810） is a novel humanized monoclonal antibody that fuses on IgG4 and targets a novel immune checkpoint protein, BTN1A1+.This is an phase Ib bridging trial conducted in China to assess the safety, tolerability, and pharmacokinetic characteristics of Nelmastobart in combined with TAS-102 and Bevacizumab in Chinese participants with mCRC, and to verify that the safety results align with those from the Korean STCUBE-003 phase Ib trial. The phase Ib trial will also provide supportive data for conducting a randomized, double-blind, controlled Phase II study in China.
Participants who participate in the study must meet all of the following inclusion criteria.
Adults ≥18 years old and of any gender when signing the informed consent form.
Participants with metastatic/recurrent colorectal cancer confirmed by histopathology/cytology who have not responded to or are unable to receive standard anti-cancer therapy based on oxaliplatin and irinotecan. Participants who undergo curative surgery for colorectal cancer and receive adjuvant anti-cancer therapy will be considered to have received their first palliative anti-cancer therapy if their disease recurs during or within 6 months after completion of the adjuvant anti-cancer treatment.
According to the Response Evaluation Criteria in Solid Tumors (RECIST) version 1.1, there must be at least one measurable or assessable lesion present.
Participants who meet any of the following exclusion criteria will be excluded from the study.
Participants who have hypersensitivity to the active ingredient of IP or any of its components (excipients)
Participants who had cytotoxic chemotherapy within 14 days prior to randomization; treatment with IP in another clinical trial with the elapse of ≤2 weeks from the last dose of that IP or ≤5 folds the half-life of that IP; or treatment with monoclonal antibody therapy within the past 4 weeks
Uncontrolled serious infection