Dermatomyositis (DM) is a systemic inflammatory disease predominantly affecting the skin and muscles, with potential involvement of internal organs. Despite multiple therapeutic options, treatment response may be unsatisfactory. Type I interferon (IFN) signaling pathways have been proposed as key drivers of disease pathogenesis. Consequently, treatment with anifrolumab, a monoclonal antibody targeting IFN receptor-1, may offer therapeutic benefit. To date, only a few cases of refractory DM successfully treated with anifrolumab have been reported. We present 2 cases of refractory DM treated with anifrolumab achieving an almost complete cutaneous response. Longitudinal evaluation of the type-I IFN signature revealed a decrease during treatment. These findings support the hypothesis that type I IFN plays a pathogenic role in DM, especially in patients with refractory disease. In this context, we aim to highlight the importance of considering anifrolumab as a therapeutic option and underscore the potential of the IFN signature as a biomarker of treatment response.
Gimeno-Ribes et al. (2026) studied this question.