A Study Evaluating Safety and Pharmacokinetics of ABBV-221 in Subjects With Advanced Solid Tumor Types Likely to Exhibit Elevated Levels of Epidermal Growth Factor Receptor

* Eastern Cooperative Oncology Group (ECOG) performance status 0 or 2. * Has a solid tumor likely to exhibit elevated levels of EGFR (e.g. head and neck squamous cell carcinoma, non-small cell lung cancer, triple negative breast cancer ,colorectal carcinoma and glioblastoma multiforme). * Has an archived, diagnostic tumor tissue available for analysis. * Has adequate hematologic, renal, cardiac and hepatic function. * Expanded Safety Cohort participants must have confirmed metastatic lung cancer and progressed after receiving prior platinum-containing chemotherapy.

* Previously received an EGFR-directed monoclonal antibody within the past 4 weeks. * Has unresolved, clinically significant toxicities from prior anti-cancer therapy defined as \> Grade 1 on Common Terminology Criteria for Adverse Events. * History of major immunologic reaction to any IgG containing agent. * Any medical condition which in the opinion of the investigator places the participant at an unacceptably high risk for toxicities.