Abstract
Objective
Calcinosis cutis (CC) is dystrophic calcification affecting 20% to 40% of patients with juvenile dermatomyositis (JDM). Management of CC is often challenging owing to its being refractory to usual therapeutic options. Type I interferon (IFN)‐mediated immune dysregulation may be involved in the pathogenic role in CC, suggesting that altering JAK/STAT signaling through JAK inhibitors might offer a therapeutic benefit.
Methods
In this open‐label, single‐arm study, the primary objective was to study the effect of tofacitinib (MSN Pharmaceuticals) on the burden of CC in children (2–18 years) with JDM, as assessed by the Agatston score using a low‐dose whole‐body computed tomography scan at 24 ± 2 weeks follow‐up. Secondary objectives were to evaluate the effect on Cutaneous Dermatomyositis Disease Area and Severity Index, Childhood Myositis and Assessment scales, steroid usage, IFNα and IFNβ levels and adverse events. Children with JDM and clinical or radiologic evidence of CC were enrolled for this study. The study drug tofacitinib was administered orally as per the standard doses based on the participant's weight band. The standard therapy included concomitant steroids, methotrexate and/or mycophenolate mofetil, and/or intravenous immunoglobulin. Those who received cyclophosphamide or rituximab in the preceding six months, were receiving concomitant topical tacrolimus, had active tuberculosis, or had hematologic abnormalities were excluded.
Results
Twenty children (11 boys) with a mean age of 10.4 (SD 3.6 years) completed the study. Eighteen children had CC associated with JDM, whereas two had JDM‐systemic sclerosis overlap. Median duration of CC in the study population was 31 (interquartile range [IQR] 19.5–54) months. There was a significant reduction in the Agatston score, median at follow‐up compared to baseline 6,349 (IQR 3,765–65,255) versus 4,007 (1,616–55,515),
P
= 0.012, with a moderate effect size (d‐robust −0.52). No serious adverse events were noted during the study period.
Conclusion
Tofacitinib, when added to standard therapy, reduced the Agatston score in children with CC associated with JDM. No major safety signals were observed during the study period.
Clinical Trials Registry ‐ India: CTRI/2024/02/062740.
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