Adalimumab in Axial Spondyloarthritis (ASIM) - MRI and Biomarkers in Patients With Spondyloarthritis

Inclusion Criteria: * Spondyloarthritis (SpA) according to the new ASAS criteria for axial SpA * BASDAI \> 40 mm despite NSAIDs * Clinical indication for treatment with TNF-alpha inhibitor * Age \> 18 years old and \< 85 years old * Sufficient contraception for women * Capable of giving informed consent * Capable of complying with the examination program of the protocol Exclusion Criteria: * Pregnancy wish, pregnancy or breast-feeding * DMARDs within 4 weeks prior to inclusion * Oral, intra-articular or intramuscular glucocorticoid within 4 weeks prior to inclusion * The use of other study drugs within 4 weeks prior to inclusion or less than 5 half-lives of the study drug before inclusion if this is more than 4 weeks * The use of suspected disease-modifying or immunosuppressive drugs within 4 weeks prior to inclusion * DMARDs are allowed during the study, but the dose cannot be changed from 4 weeks prior to inclusion through week * Contraindications for TNF-α inhibitor treatment * Contraindications for MRI * Known recent drug or alcohol abuse * Failure to provide written consent * Incapable of complying with the examination program for physical or mental reasons