Effect of Baricitinib Treatment on Peripheral Bone in RA

Inclusion Criteria: * Main inclusion criteria: Patients eligible for inclusion in this study have to fulfil all of the following criteria: * Subject must be able to understand and communicate with the investigator and comply with the requirements of the study, must give a written and signed and dated informed consent before any study assessment is performed * Male or non-pregnant, non-lactating female subjects aged between 18 - 74 * Women of childbearing potential must oblige to use a highly effective method of birth control until at least 4 weeks after the last IMP administration * Diagnosis of RA according to the ACR/EULAR criteria and with symptoms for at least 3 months with moderate to severe RA * pathologic volumetric bone density, microstructure or presence of erosions detected by HR-pQCT and or MRI measurement * Previous treatment with at least one DMARD (e.g. methotrexate) without sufficient clinical response or stopped due to toxicities * Fulfil criteria for baricitinib treatment according to its SmPC Exclusion Criteria: * Ongoing pregnancy status or breast-feeding * Chest X-ray or chest MRI with evidence of ongoing infectious or malignant process, obtained within 3 months or according to local guidelines, prior to screening and evaluated by a qualified physician * Contraindication for baricitinib treatment according to its SmPC * Current treatment with bDMARDs or other JAK-inhibitors * Creatinine clearance \< 60ml/min (calculated analogue MDRD) * Cur…