labetuzumab labetuzumab labetuzumab (marketed under the trade name cea-cide) is a humanized igg1 monoclonal antibody for the treatment of colorectal cancer. it selectively binds to carcinoembryonic cell adhesion molecule 5. labetuzumabmonoclonal antibodytypewhole antibodysourcehumanized (from mouse)targetcarcinoembryonic antigenclinical dataatc codenoneidentifierscas number219649-07-7 nchemspidernoneuniiefe6x5m3uykeggd08936 y ny (what is this?) (verify) also tried in patients with mtc (medullary thyroid carcinoma) with metastasis. this drug was developed by immunomedics, inc.