Clinical Research Directory

Inclusion Criteria: 1. Previous inclusion in the REScUE study and having reached the end of this study at week 48. 2. Adequate contraception in females of reproductive age (oral, transdermal, injectable contraception, intra-uterine device, sterilisation or barrier method). Adequate contraception in males (sterilization or barrier method) if his female partner is of reproductive age. 3. Have the capacity to understand and sign an informed consent form. 4. Be able to adhere to the study visit schedule and other protocol requirements. Exclusion Criteria: 1. Patients previously enrolled to the ustekinumab 90 mg SC Q4w-arm during REScUE who were on concomitant steroid use \>20 mg prednisone equivalents (budesonide \>6 mg; beclomethasone dipropionaat \>5 mg) at any time point in the last 28 days before the end of REScUE at week 48. 2. Patients previously enrolled to the ustekinumab 90 mg SC Q4w-arm during REScUE that did not reach the following criteria at the end of REScUE at week 48: * Clinical remission (defined as average AP\<=1 and average SF\<=3) OR clinical response (defined as a drop of at least 50% in average AP and/or a drop of at least 50% in average SF as compared to REScUE baseline, and both average AP and SF no worse than REScUE baseline) AND * Endoscopic remission (defined as a total SES-CD \<5) OR endoscopic response (defined as a drop of at least 50% in total SES-CD score as compared to REScUE baseline) 3. Patients who developed an anaphylactic or severe allergic reaction to study medication during REScUE. 4. Patients with any of the following laboratory tests at W0 of the REScUE-OLE study : * Hemoglobin level \<8.5 g/dL * Platelets level \<100.000 /mm3 * Serum creatinine level ≥1.7 mg/dL * AST and ALT level \>3 times the upper limit of normal range * Direct (conjugated) bilirubin level ≥3.0 mg/dL 5. Patients with an ongoing treatment with another concomitant biological (vedolizumab, anti-TNF), a JAK-inhibitor or any investigational product for the treatment of Crohn's disease at the end of REScUE at week 48. 6. Patients who experience or have an ongoing infection event confirmed by positive stool or blood testing (including gastrointestinal pathogens, tuberculosis, HIV, hepatitis B, hepatitis C) should not initiate REScUE-OLE until (i) this event has completely resolved as shown by the termination of treatment with anti-infective medication, or (ii) this event is considered to be in stable remission under anti-infective medication in case of HIV, hepatitis B and hepatitis C. 7. Patients with an impassable stenosis even after attempt of endoscopic balloon dilatation. 8. Patients with an intra-abdominal abscess, or patients with an intra-anal abscess without adequate drainage by e.g. a seton placement.