A Study to Investigate the Safety, Tolerability, Pharmacokinetics, and Anti-tumor Activity of CBI-1214 T Cell Engager in Participants With Advanced or Metastatic MSS/MSI-L Colorectal Cancer

Required: MMR proficient (MSS/MSI-L)

Participant with MSS/MSI-L CRC

Excluded: MMR deficient

Participant whose CRC tumor tissues have been identified as dMMR or MSI-H

Allowed: BRAF V600E

BRAFV600E mutations, for which FDA-approved targeted therapies are available, must: Have received prior treatment with applicable FDA-approved targeted therapies AND Either have experienced disease progression, be refractory, or be intolerant to directed molecular therapy.

Allowed: HER2 (ERBB2) amplification

HER2 amplifications, for which FDA-approved targeted therapies are available, must: Have received prior treatment with applicable FDA-approved targeted therapies AND Either have experienced disease progression, be refractory, or be intolerant to directed molecular therapy.

Must have received: standard systemic therapy — current malignancy

exhausted at least one prior line of standard systemic therapy for their current malignancy

Must have received: FDA-approved targeted therapy — for genomic aberrations (e.g. BRAFV600E, HER2 amplification)

Have received prior treatment with applicable FDA-approved targeted therapies AND Either have experienced disease progression, be refractory, or be intolerant to directed molecular therapy.