An Extension Study to Demonstrate the Equivalence of Long-Term Efficacy and Safety of CT-P13 in Patients With Ankylosing Spondylitis Who Were Treated With Infliximab (Remicade or CT-P13) in Study CT-P13 1.1

Inclusion Criteria: * Patient who has completed the scheduled visits, including the End-of-Study Visit, in Study CT-P13 1.1 * Patient who has not had any major protocol violation in Study CT-P13 1.1 Exclusion Criteria: * Patient who has been withdrawn from Study CT-P13 1.1 for any reason * Patient who, at the time of providing informed consent, has any ongoing medical issues such as serious adverse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 option of the investigator * Patient who plans to participate in a study with an investigational drug during the period of this extension study