All patients who received ≥1 dose of pralatrexate were evaluable for safety, which was assessed by reported AEs, laboratory assessments, and physical examinations, and graded according to the National Cancer Institute Common Terminology Criteria for Adverse Events scale, version 4.03. AEs were characterized by intensity (severity), causality, and seriousness by the investigator and recorded from the first dose of pralatrexate until at least 30 days after the last dose.