Crohn's Disease: Efficacy, Safety, and Pharmacokinetics of Upadacitinib in Pediatric Subjects With Moderately to Severely Active Crohn's Disease

Crohn's disease (CD) is a long-lasting disease that causes severe inflammation (redness, swelling), in the digestive tract, most often affecting the bowels. It can cause many different symptoms including abdominal pain, diarrhea, tiredness, and weight loss. This study will assess how safe and effective oral Upadacitinib is in treating moderately to severely active Crohn's Disease in pediatric participants aged 2 to 18 years old who have had inadequate response, loss of response, intolerance, or medical contraindications to corticosteroids, immunosuppressants, and/or biologic therapy. Upadacitinib (RINVOQ) is a drug approved in adults for moderate- to severely active CD and is being developed for moderate- to severely active CD in pediatric participants. This study is conducted in 2 periods: Period 1 is comprised of two phases: a 12-week open-label induction phase which means that the study doctor and participants know that participants will receive UPA Dose-A (or the adult equivalent based on body weight) followed by a 52-week double-blind maintenance phase meaning that neither the participants nor the study doctors will know which dose of upadacitinib will be given (UPA Dose B or Dose C). Period 2 is a 156-week open-label extension of Period 1. Approximately 110 pediatric participants with moderate to severely active CD will be enrolled at approximately 92 sites worldwide. Participants will receive upadacitinib oral tablets once daily or oral solution twice daily at approximately the same time each day, with or without food. Participants will have a safety follow up for 30 days after discontinuation from any time point within the study. There may be higher treatment burden for participants in this trial compared to their standard of care (due to study procedures). Participants will attend regular (weekly, monthly) visits during the study at a hospital or clinic. The effect of the treatment will be checked by medical assessments, blood tests, checking for side ef