Real-world experience of anifrolumab in 30 patients with refractory DM: a multicentre-multidisciplinary retrospective...

To assess real-world outcomes of anifrolumab (ANI) in refractory systemic DM.

This multicentre and multidisciplinary, retrospective study evaluated 30 DM patients receiving ANI through compassionate use. Disease activity was assessed at baseline and months 1, 3, 6 and 12 using Cutaneous Dermatomyositis Disease Area and Severity Index Activity Score (CDASI-A), Manual Muscle Testing-8 (MMT-8), joint and pulmonary evaluation and glucocorticoid tapering. Safety included adverse event documentation and treatment discontinuation rates.

Treatment indications included refractory cutaneous (73.3%), cutaneous-muscular (13.4%, including one pulmonary progression case) and other manifestations (13.3%). ANI was initiated without concomitant immunosuppressive therapy in 50% of patients. Cutaneous improvement was observed from month 1 (CDASI-A: 23 [IQR 10.8-30.5] to 6 [IQR 3-10]; P < 0.001), with heliotrope rash and Gottron's papules responding faster than alopecia. Muscular function improved (MMT-8: 142.5 [IQR 127-148] to 146.5 [IQR 139-150]; P < 0.05) with creatine kinase (CK) normalization (332 IU/l [IQR 211.5-893.5] to 146 IU/l [IQR 106.5-481.8]) at month 1. All active arthritis patients (n = 3) achieved remission, with no articular flares observed among patients with historical joint involvement. Interstitial lung disease cases (n = 6) demonstrated stabilization or improvement as assessed by pulmonary function tests and/or computed tomography. Glucocorticoid dose significantly reduced (P < 0.001), discontinued in 50%. Adverse events were mild (16.7% patients); one 89-year-old patient died from pneumonia. One patient required upadacitinib for refractory pruritus; one discontinued ANI for efficacy loss.

ANI showed rapid, multisystem efficacy in refractory DM with significant steroid-sparing effects and a favourable safety profile.