Owing to the high affinity of cibisatamab to CEA and consistent with cibisatamab positron emission tomography (PET) imaging studies in tumour-bearing mice23 and a clinical imaging study with a labeled molecule (89Zr CEA-IL2v) that binds to the same CEA epitope as cibisatamab24, tumour retention is predicted to be considerably longer than that based on the serum PK half-life, which further supported the Q3W schedule. Here, CEACAM5 is linked to neoplasm.