Inhibiting interferon pathways in dermatomyositis: rationale and preliminary evidence.

Purpose of review: Dermatomyositis (DM) is a systemic autoimmune disease affecting multiple organs, including skeletal muscle, skin, and lungs. Although DM disease mechanisms are incompletely understood, accumulating evidence suggests that interferons may play a significant role. Consequently, it is of considerable interest that drugs blocking the activity of interferons by inhibiting the Janus Kinase/Signal Transducer and Activator of Transcription (JAK-STAT) pathway have been approved for use in other autoimmune diseases. This manuscript will examine the IFN pathways and their importance in DM, review the existing literature on the use of JAK-STATs inhibitors in patients with adult or juvenile DM, and discuss the potential utility of JAK-STAT inhibitors to treat this disease. Recent findings: Recent reports suggest that muscle and skin involvement in patients with either adult or juvenile DM respond favorably to JAK-STAT inhibitors. Moreover, preliminary data indicates that JAK-STAT inhibitors may be useful to treat clinical manifestations of this disease that are complicated to manage otherwise, such as calcinosis or rapidly progressive interstitial lung disease in DM patients with anti-MDA5 autoantibodies. Summary: An increasing number of reports suggest that JAK-STAT inhibitors may be useful to treat the varied manifestations of adult and juvenile DM. However, as most studies were either small or lacked appropriate comparators, further research will be necessary to define the role of these drugs in DM treatment.