Long-term Safety Evaluation of Guselkumab in Pediatric Patients with Moderately to Severely Active Crohn's Disease, Ulcerative Colitis, or Juvenile Psoriatic Arthritis

The primary objective of this Phase 3, multicenter, open-label, basket, long-term extension study is to evaluate the long-term **safety** of **guselkumab** in pediatric participants with moderately to severely active **ulcerative colitis**, moderately to severely active **Crohn's disease**, or **juvenile psoriatic arthritis**. The clinical relevance of this objective lies in the need to ensure the safety of long-term treatment with guselkumab in these pediatric populations, as these conditions often require extended management strategies. No secondary objectives are specified for this study.

The clinical trial involves a total of **93 participants** diagnosed with **moderately to severely active Crohn's disease**, **ulcerative colitis**, or **juvenile psoriatic arthritis**. The study population includes both male and female subjects, categorized within age ranges 2 and 3, indicating a pediatric cohort. Participants were selected based on their completion of the dosing planned in the primary pediatric guselkumab study and the perceived benefit from continued guselkumab therapy. The trial includes a vulnerable population, necessitating informed consent from parents or legally designated representatives, with assent required from children capable of understanding the study. Participants must adhere to specified lifestyle restrictions, although specific details on diet, physical activity, or habits are not provided. The trial aims to evaluate the long-term safety of guselkumab in this pediatric population.

The clinical trial is a Phase 3, multicenter, open-label, long-term extension study designed to evaluate the safety of **guselkumab** in pediatric participants with moderately to severely active **Crohn's disease**, **ulcerative colitis**, or **juvenile psoriatic arthritis**. The trial employs a basket design, allowing for the inclusion of participants with different conditions under a single protocol. The study is not randomized or blinded, as it focuses on long-term safety rather than efficacy endpoints. The trial is expected to run until December 2031, with recruitment starting in October 2024.

Participants eligible for the study must have completed the dosing planned in the primary pediatric guselkumab study and must have received benefit from continued guselkumab therapy, as determined by the investigator. The study involves several key visits, beginning with an inclusion (screening) visit to confirm eligibility based on the inclusion criteria. Follow-up visits will be scheduled to monitor the safety and any adverse effects of the treatment. The end-of-study visit will conclude the participant's involvement, ensuring all safety data is collected and any necessary follow-up care is arranged.

The expected length of participant involvement is up to 52 weeks, corresponding to the maximum treatment period. Participants may be terminated early from the study if they experience significant adverse effects, fail to adhere to the study protocol, or withdraw consent. The study does not collect primary or secondary endpoints, focusing solely on the safety profile of guselkumab in the specified pediatric population. The trial will utilize a solution for injection in pre-filled syringes, administered subcutaneously or subdermally, depending on the formulation used. The study aims to provide valuable safety data to support the long-term use of guselkumab in pediatric patients with these chronic conditions.

The clinical trial involves the administration of **Guselkumab**, a monoclonal antibody, in various formulations. The primary experimental medication is Guselkumab, provided as a **solution for injection in a pre-filled syringe**. This formulation is intended for **subcutaneous use**. The medication is administered using the VarioJect™ variable dose injector, which is a drug delivery device component of a biological drug-device combination product. The dosing schedule is designed for a maximum treatment period of 52 weeks. The specific dosage in milligrams is not predetermined, as the maximum daily and total dose amounts are set to zero, indicating flexibility in dosing based on clinical judgment and participant response. Participant compliance is monitored through regular follow-ups and assessments.

Another formulation of Guselkumab is also used in the trial, which is similarly a **solution for injection in a pre-filled syringe** but intended for **subdermal use**. This formulation is administered using the 2 mL UltraSafe Plus™ Passive Needle Guard, which facilitates manual injection and enables passive activation of a needle guard after delivery. Like the previous formulation, the dosing schedule allows for a maximum treatment period of 52 weeks, with no fixed maximum daily or total dose amounts, allowing for individualized dosing based on participant needs and clinical outcomes.

The third formulation of Guselkumab used in the trial is a **solution for injection/infusion** in a pre-filled syringe with a concentration of 100 mg/mL. This formulation is also intended for **subcutaneous use** and is administered using the 1 mL UltraSafe Plus™ Passive Needle Guard. The dosing schedule for this formulation is consistent with the other formulations, with a maximum treatment period of 52 weeks and no predetermined maximum daily or total dose amounts. This approach ensures that dosing can be tailored to the specific requirements of each participant, enhancing the safety and efficacy of the treatment.

Throughout the trial, no non-experimental treatments such as standard-of-care therapy, placebo, or comparator treatments are specified. The focus remains on evaluating the long-term safety of Guselkumab in pediatric participants with moderately to severely active ulcerative colitis, Crohn's disease, or juvenile psoriatic arthritis. Compliance with the treatment regimen is closely monitored through scheduled visits and assessments to ensure adherence and to evaluate the safety profile of the medication over the course of the study.

The clinical trial is designed to evaluate the long-term safety of **guselkumab** in pediatric participants with moderately to severely active ulcerative colitis, Crohn's disease, or juvenile psoriatic arthritis. The study is a Phase 3, multicenter, open-label, basket, long-term extension study. The primary objective is to assess the safety profile of guselkumab over an extended period. No primary or secondary efficacy endpoints will be collected in this study, as the focus is solely on safety evaluation.