Study to Evaluate the Safety, Tolerability, Pharmacokinetics, and Pharmacodynamics of Single Ascending Doses of KPL-404 in Healthy Subjects

This study includes 2 single ascending dose (SAD) parts; (Part A) IV SAD (up to 5 planned dose level cohorts) and Part B SC SAD (up to 3 planned dose level cohorts). Safety assessments will include adverse events (AEs), concomitant medications, clinical laboratory, vital signs, 12-lead electrocardiogram, and physical examination. Serial blood samples for PK, PD, and anti-drug antibodies will be performed during each part of the study during the Treatment and Safety Evaluation Period.