BCD-055-2 is international multi-center comparative double-blind randomized clinical trial to evaluate efficacy and safety of BCD-055 (JSC "BIOCAD", Russia) and Remicade® in patients with ankylosing spondylitis.

BCD-055 is biosimilar of infliximab (JSC "BIOCAD", Russia)

Inclusion Criteria:

• Signed informed consent
• Active ankylosing spondylitis according to modified criteria of New York classification (1984), that was diagnosed at least 3 months prior to screening.
• Active disease according to BASDAI (score 4 or more) if nonsteroidal antiinflammatory drugs were used in the last 3 month prior to screening.
• Mean backache intensity equals 4 points or more.

Exclusion Criteria:

• Previous therapy of ankylosing spondylitis with monoclonal antibodies (including tumor necrosis factor)
• Total spinal ankylosis
• History of tuberculosis
• Body mass more than 120 kg
• Patient is taking corticosteroids for up to 4 weeks in a dose more than 10 mg (recalculated to prednisolone) before signing informed consent.
• Prior use of disease-modifying antirheumatic drugs including methotrexate, sulfasalazin, chloroquine or hydroxychloroquine for up to 4 weeks before randomization.
• Prior use of alkylating agents for up to 12 months prior to signing informed consent.
• Intraarticular use of corticosteroids for up to 4 weeks before randomization.
• Prior use of live or attenuated vaccines for up to 8 weeks before signing informed consent.