Meta-analyses uncover the genetic architecture of Idiopathic Inflammatory Myopathies.

Objective: Idiopathic inflammatory myopathies (myositis, IIMs) are rare, systemic autoimmune disorders that lead to muscle inflammation, weakness, and extra-muscular manifestations, with a strong genetic component influencing disease development and progression. Previous genome-wide association studies identified loci associated with IIMs. In this study, we imputed data from two prior genome-wide myositis studies and analyzed the largest myositis dataset to date to identify novel risk loci and susceptibility genes associated with IIMs and its clinical subtypes.

Autoantibodies against a subunit of mitochondrial respiratory chain complex I in inclusion body myositis.

Background: Autoantibodies are found in up to 80 % of patients with idiopathic inflammatory myopathies (IIM) and are associated with distinct clinical phenotypes. Autoantibodies targeting cytosolic 5'-nucleotidase 1A (anti-NT5C1A) are currently the only known serum biomarker for the subgroup inclusion body myositis (IBM), although detected even in other autoimmune diseases. The aim of the study was to identify new autoimmune targets in IIM.

Subcutaneous efgartigimod PH20 in generalized myasthenia gravis: A phase 3 randomized noninferiority study (ADAPT-SC) and interim analyses of a long-term open-label extension study (ADAPT-SC+).

ADAPT-SC (NCT04735432) was designed to evaluate noninferiority of subcutaneous (SC) efgartigimod PH20 to intravenous (IV) efgartigimod in participants with generalized myasthenia gravis (gMG). ADAPT-SC+ (NCT04818671) is an open-label extension study designed to assess long-term safety, tolerability, and efficacy of efgartigimod PH20 SC. Adult participants in ADAPT-SC were randomly assigned to receive a treatment cycle of 4 once-weekly administrations of efgartigimod PH20 SC 1000 ​mg or efgartigimod IV 10 ​mg/kg, followed by 7 weeks of follow-up.

Congenital Myasthenic Syndromes in Belgium: Genetic and Clinical Characterization of Pediatric and Adult Patients.

Background: Congenital myasthenic syndromes (CMS) are a group of genetic disorders characterized by impaired neuromuscular transmission. CMS typically present at a young age with fatigable muscle weakness, often with an abnormal response after repetitive nerve stimulation (RNS). Pharmacologic treatment can improve symptoms, depending on the underlying defect.