A Phase 1, 2-Part, Randomized, Double-Blind, Parallel-Group, Single-Dose Study to Compare the Pharmacokinetics, Safety and Immunogenicity of Three Subcutaneous Injection Formulations of Ustekinumab in Healthy Male Subjects

CT-P43 is being developed as a proposed biosimilar of Stelara (ustekinumab). This study will be conducted in 2 parts. In Part 1, subjects will be enrolled and randomized in a 1:1 ratio to receive a single dose (45 mg) of either CT-P43 or EU-approved Stelara to collect preliminary safety data for CT-P43. In Part 2, subjects will be enrolled and randomized in a 1:1:1 ratio to receive a single dose (45 mg) of CT-P43, EU-approved Stelara, or US-licensed Stelara to demonstrate PK similarity. Each part will proceed independently, and subjects will be randomized to either Part 1 or Part 2 of the study subsequently. All subjects in Part 1 and Part 2 will undergo the same assessments. In each treatment arm in Part 1 and Part 2, all subjects will receive a study drug subcutaneously via PFS. The randomization to treatment assignment will be stratified by study center and body weight as measured at baseline to balance subject weight across treatment groups. Subjects will be confined to the study center until all required 24-hour post-dose assessments have been completed and will be discharged on Day 2. Subsequent visits will be carried out on an out-patient basis up to EOS.