The role of bDMARDs in idiopathic inflammatory myopathies: A systematic literature review

Janus kinase inhibition (JAKi) therapy in refractory anti-synthetase syndrome: A retrospective cohort study

OBJECTIVES

To evaluate the efficacy and safety of Janus kinase inhibitors (JAKi) in the treatment of refractory anti-synthetase syndrome (ASS) in real-world clinical settings.

METHODS

The medical records of all refractory ASS patients who were treated with JAKi from October 2020 to June 2023 were retrospectively reviewed.

RESULTS

Twenty patients were included, and all (100 %) patients had interstitial lung disease (ILD). After treatment with JAKi, 14 (70 %) of the refractory ASS patients showed significant improvement in clinical manifestations, including arthritis (56.3 % vs. 6.3 %, p = 0.002), rash (77.8 % vs. 27.8 %, p = 0.012), shortness of breath (55.6 % vs. 16.7 %, p = 0.039), cough (61.1 % vs. 11.1 %, p = 0.012). Improvement was noted for myalgia (50 % vs. 11.1 %, p = 0.016) and muscular weakness (61.1 % vs. 11.1 %, p = 0.012), while creatine kinase (CK) levels, which were abnormally elevated in five patients prior treatment, were significantly lowered (1096 ± 1042.98 IU/L vs. 199.2 ± 144.66 IU/L, p = 0.043). A decrease in levels of inflammatory markers, including erythrocyte sedimentation rate (ESR) (p = 0.001) and C-reactive protein (CRP) (p = 0.023) was observed in the patients. In ASS-ILD, the CT score reduced (188.75 ± 69.67 vs. 156.35 ± 74.62, p = 0.001). Furthermore, the glucocorticoid dose significantly reduced (21.42 ± 13.26 mg vs. 11.32 ± 8.59 mg; p = 0.001).

CONCLUSIONS

JAKi were effective in most refractory ASS patients as evidenced by improved skin rash, myositis, and ILD. However, larger prospective controlled studies are required to evaluate its efficacy.

The interferon in idiopathic inflammatory myopathies: Different signatures and new therapeutic perspectives. A literature review

Idiopathic inflammatory myopathies (IIM), even though sharing common clinical manifestations, are characterized by diversified molecular pathogenetic mechanisms which may account for the partial inefficacy of currently used immunomodulatory drugs. In the last decades, the role of interferon (IFN) in IIM has been extensively elucidated thanks to genomic and proteomic studies which have assessed the molecular signature at the level of affected tissues or in peripheral blood across distinct IIM subtypes. A predominant type I IFN response has been shown in dermatomyositis (DM), being especially enhanced in MDA5+ DM, while a type 2 IFN profile characterizes anti-synthetase syndrome (ASyS) and inclusion body myositis (IBM); conversely, a less robust IFN footprint has been defined for immune-mediated necrotizing myopathy (IMNM). Intracellular IFN signaling is mediated by the janus kinase/signal transducer and activator of transcription (JAK/STAT) through dedicated transmembrane receptors and specific cytoplasmic molecular combinations. These results may have therapeutic implications and led to evaluating the efficacy of new targeted drugs such as the recently introduced janus kinase inhibitors (JAKi), currently approved for the treatment of rheumatoid arthritis, psoriatic arthritis, and ankylosing spondylitis. In this review we aim to summarize the most significant evidence of IFN role in IIM pathogenesis and to describe the current state of the art about the ongoing clinical trials on IFN-targeting drugs, with particular focus on JAKi.