Inclusion criteria:

          1. Male or female ≥ 18 years of age

          2. Documented pCAD expressing tumor cells with the exception of HNSCC and ESCC. An
             archived tumor sample collected within 36 months prior to baseline if available, or a
             new tumor biopsy sample must be available for molecular pre-screening.

          3. Consent for a tumor biopsy at screening

          4. Progressive disease and no effective therapy exists

          5. Measurable disease as per RECIST v1.1 criteria

          6. ECOG Performance status of ≤ 2

        Exclusion criteria:

          1. CNS metastatic involvement

          2. Clinically significant cardiac, respiratory, gastrointestinal, renal, hepatic or
             neurological conditions.

          3. A history of serious allergic reactions, which in the opinion of the investigator pose
             an increased risk of serious infusion reactions.

          4. Monocular vision or has media opacities or any other condition that precludes
             monitoring of the retina or the fundus, or has a history of ophthalmology exam with
             retina or cornea abnormalities

          5. Previously treated with anti-pCAD biologic therapies.

          6. Received anti-cancer therapies within the following time frames prior to the first
             dose of study treatment:

               -  Conventional cytotoxic chemotherapy: ≤4 weeks

               -  Biologic therapy (eg, antibodies), other than ADCs: ≤4 weeks

               -  Non-cytotoxic small molecule therapeutics: ≤5 T1/2 or ≤2 weeks (whichever is
                  longer)

               -  Other investigational agents: ≤4 weeks

               -  Radiation therapy (palliative setting is allowed.): ≤4 weeks

               -  Major surgery: ≤2 weeks

          7. Patient has out of range laboratory values defined as:

               -  Hematological values:

               -  Absolute neutrophil count (ANC) <1.5 x 109/L

               -  Hemoglobin (Hgb) <9 g/dL

               -  Platelets <100 x 109/L

               -  Hepatic and renal function

               -  Total bilirubin >1.5 x upper limit of normal (ULN). For patients with Gilbert's
                  syndrome, total bilirubin >2.5 x ULN.

               -  Aspartate aminotransferase (AST) or alanine aminotransferase (ALT) >3 x ULN for
                  patients without tumor involvement of the liver or >5 x ULN for patients with
                  tumor involvement of the liver.

               -  Serum creatinine >1.5 x ULN and/or measured creatinine clearance < 40 ml/min