Evaluating Safety and Drug Levels of Bimekizumab in Children Ages 2 to Under 18 with Active Juvenile Enthesitis-Related Arthritis or Juvenile Psoriatic Arthritis

What this Trial Is About

Researchers are studying children aged 2 to under 18 years who have active juvenile enthesitis-related arthritis, including juvenile-onset ankylosing spondylitis, or juvenile psoriatic arthritis. The study aims to assess the levels of the drug bimekizumab in the blood after it is given by subcutaneous injection. This Phase 3 trial evaluates the safety and drug concentrations to better understand how bimekizumab behaves in pediatric participants with these specific types of juvenile arthritis. Participants will receive bimekizumab doses adjusted according to their weight, administered at specific times during the study. The initial treatment period lasts up to 16 weeks. The study also includes an extended safety follow-up of up to 141 weeks to monitor for any adverse events or side effects. No placebo or comparison group is used all participants receive the active drug. Throughout the study, participants will undergo regular assessments including blood tests to measure drug levels, vital signs, biochemistry and hematology parameters, growth measurements, and evaluations of arthritis disease activity. Researchers will also monitor adverse events, including specific infections and injection site reactions. The study tracks responses using standardized juvenile arthritis scores at Week 16. Participants are followed closely for safety and treatment effects throughout the treatment and follow-up periods, which may last several years.

An Open-label Study to Evaluate the Pharmacokinetics and Safety of Bimekizumab in Pediatric Study Participants With Active Juvenile Idiopathic Arthritis Subtypes Enthesitis-related Arthritis (Including Juvenile-onset Ankylosing Spondylitis) and Juvenile Psoriatic Arthritis