It is planned to enroll 80 UC patients who will require optimization of golimumab after secondary LOR. The review of the study protocol and its approval by an Independent Ethics Committee of the University of Saint Etienne are pending. All patients enrolled will give their written informed consent before being included. This study will be conducted in accordance with the ethical principles that have their origins in the Declaration of Helsinki, in compliance with the approved protocol, good clinical practice and applicable regulatory requirements. Patients will visit the investigator from screening visit to visit 6 at W-1, W0, W2, W4, W8, and at the end of the follow-up at wk 24. During their participation, patients will record clinical parameters required to calculate the partial Mayo score reported over 3 days prior to the visit and endoscopy at W0, W2 (optional) , W4, W8 (optional) and at the end of the follow-up to calculate total Mayo score.

Inclusion Criteria:

• Affiliate or beneficiary of social security
• Age>18 years
• Pregnant women or man
• Presenting primary response under golimumab induction and in loss of response during maintenance therapy
• Patient with an ulcerative colitis
• Treated with golimumab
• Signature of consent

Exclusion Criteria:

• Trying to become pregnant
• Mental or emotional disorders
• Patients with crohn's disease or indeterminate colitis
• cancer(<5)
• Patients not in agreement with this study protocol
• Patients with crohn's disease or indeterminate colitis
• Patients non primary responder to golimumab