CT-P13 (Infliximab) is a monoclonal antibody currently being developed by CELLTRION, Inc. This open-label, single-arm, multicenter, multiple single dose intravenous (IV) infusion, efficacy, and safety extension study of the Phase 3 Study CT-P13 3.1 is designed to assess the long-term efficacy and safety of multiple doses of CT-P13.

Inclusion Criteria:

• Patient who has completed the scheduled visits, including the End-of-Study Visit, in Study CT-P13 3.1
• Patient who has not had any major protocol violation in Study CT-P13 3.1
• Patient is permitted to enter the extension study if, in the option of their general practitioner or the investigator, the patient will continue to gain benefit from treatment in the extension study. Local guidelines for patient treatment will be followed

Exclusion Criteria:

• Patient who has been withdrawn from Study CT-P13 3.1 for any reason
• Patient who, at the time of providing informed consent, has any ongoing medical issues such as serious adverse events (SAEs) or intolerance issues that mean continuation in this extension study could be detrimental to their health, in the opinion of the investigator
• Patient who plans to participate in a study with an investigational drug during the period of this extension study