• Histologically or cytologically confirmed diagnosis of colorectal cancer (CRC) adenocarcinoma, nonsquamous non small cell lung cancer (NSQ NSCLC), or gastric/ gastroesophageal junction (GC/GEJ) adenocarcinoma, metastatic disease at study entry.

• Participants with documented disease progression, for which, in the judgment of the Investigator, no alternative medical therapy is available.

• Expression of carcinoembryonic antigen-related cell adhesion molecule 5 (CEACAM5) will be assessed centrally using the most recent archival tumor tissue (or, if not available, a fresh biopsy sample) and at least 5 fresh-cut slides of formalin-fixed paraffin embedded (FFPE) tumor tissue sectioned. If less material is available, the participant could still be considered eligible after discussion with the Sponsor.

‣ Participants with CRC tumors may be assumed to have adequate CEACAM5 expression without testing results (it will be assessed retrospectively),

⁃ Participants with NSQ NSCLC must have tumors expressing CEACAM5 or high circulating CEA if tumor tissue is not available.

⁃ Participants with GC/GEJ must have tumors expressing CEACAM5

• Measurable disease by Response Evaluation Criteria in Solid Tumors (RECIST) v1.1, as determined by the Investigator.

• Eastern Cooperative Oncology Group (ECOG) performance status 0 to1.

• A female participant is eligible to participate if she is not pregnant or breastfeeding, is not a woman of childbearing potential (WOCBP) and is a WOCBP and agrees to use a contraceptive method that is highly effective and for at least 7 months after the last dose of treatment. administration.

• Male participant who agrees to use effective contraception methods during and for at least 4 months after the last dose of treatment administration.

• Capable of giving signed informed consent.