A Study to Evaluate the Safety, Tolerability, Pharmacokinetics, and Antitumor Activity of ADCT-901 in Participants With Selected Advanced Solid Tumors

Exclusion Criteria

• •1. History of active infection (requiring intravenous \[IV\] antibiotics, IV antiviral or IV antifungal treatment within 4 weeks of cycle 1, day 1 \[C1D1\]).
• •2. Symptomatic central nervous system (CNS) metastases or evidence of leptomeningeal disease (brain MRI or previously documented cerebrospinal fluid cytology). Previously treated asymptomatic CNS metastases are permitted provided that the last treatment (systemic anticancer therapy and/or local radiotherapy) was completed ≥4 weeks prior to C1D1 except usage of low dose of steroids on a taper (i.e., up to 10 mg prednisone or equivalent on Day 1 and consecutive days is permissible if being tapered down). Participants with discrete dural metastases are eligible.
• •3. Clinically significant third space fluid accumulation (i.e., ascites requiring drainage or any serosal effusion that is either requiring drainage or associated with shortness of breath).
• •4. Active diarrhea ≥ Common Terminology Criteria for Adverse Events (CTCAE) Grade 2 or a medical condition associated with chronic diarrhea (such as irritable bowel syndrome, inflammatory bowel disease).
• •5. Active or clinically significant ocular surface disease at baseline. An ocular evaluation is to be confirmed by an ophthalmologist at screening. Participants with any prior episode of cicatricial conjunctivitis (as evaluated by the investigator) are ineligible.
• •Note: Mild dry eye syndrome or blepharitis managed with artificial tear drops, without injection or epithelial changes, are not exclusionary.
• •6. Use of any other experimental medication within 14 days prior to start of study drug (C1D1).