title: Use of biologic agents in idiopathic inflammatory myopathies in Sweden: a descriptive study of real life treatment.
abstract: OBJECTIVE
  Biologic treatment has revolutionised treatment in rheumatology in the last decades. Patients with idiopathic inflammatory myopathies (IIM) have so far only been treated with biologics off-label, with little published follow-up on those who are treated and how they are treated. We therefore set out to characterise the Swedish IIM patients who have been treated with biologics.
  
  
  METHODS
  By linking Swedish registers we identified 95 patients with IIM who were treated with biologics between 2000 and 2011. Via chart review the diagnoses were validated and clinical characteristics extracted.
  
  
  RESULTS
  In total, 95 individuals with IIM and biologic treatment were identified. Median disease duration was 5.5 years at start of biologics. All patients had been treated with prednisolone and failed at least one previous DMARD before the start of first biologic. Rituximab was the most common biologic drug, followed by anakinra and TNFinhibitors. Median overall treatment length was 10 months and varied between 5 and 12.5 months or the different therapies.
  
  
  CONCLUSIONS
  Off-label treatment of IIMs is often tried and seldom successful. This study shows a large unmet need for novel treatments and therapies in IIM. It is therefore important to follow these patients in a structured way to learn about effects and potential risks for different subgroups of IIM associated with different therapies.
authors.affiliation: Rheumatology unit, Department of Medicine Solna, Karolinska University Hospital, Karolinska Institutet, Stockholm, Sweden. john.svensson@ki.se.
authors.forename: John
authors.initials: J
authors.lastname: Svensson
authors.affiliation: Unit of Clinical Epidemiology, Department of Medicine Solna, Karolinska University Hospital, Karolinska Institutet, Stockholm, Sweden.
authors.forename: Marie
authors.initials: M
authors.lastname: Holmqvist
authors.affiliation: Rheumatology unit, Department of Medicine Solna, Karolinska University Hospital, Karolinska Institutet, Stockholm, Sweden.
authors.forename: Anna
authors.initials: A
authors.lastname: Tjärnlund
authors.affiliation: Rheumatology unit, Department of Medicine Solna, Karolinska University Hospital, Karolinska Institutet, Stockholm, Sweden.
authors.forename: Maryam
authors.initials: M
authors.lastname: Dastmalchi
authors.affiliation: Sahlgrenska University Hospital, Gothenburg, Sweden.
authors.forename: Balsam
authors.initials: B
authors.lastname: Hanna
authors.affiliation: Örebro University Hospital, Örebro, Sweden.
authors.forename: Sara
authors.initials: S
authors.lastname: Magnusson Bucher
authors.affiliation: Rheumatology unit, Department of Medicine Solna, Karolinska University Hospital, Karolinska Institutet, Stockholm, Sweden.
authors.forename: Ingrid E
authors.initials: IE
authors.lastname: Lundberg
mesh_terms: D000293:Adolescent; D000368:Aged; D000893:Anti-Inflammatory Agents / Q000009:adverse effects / Q000627:therapeutic use*; D001688:Biological Products / Q000009:adverse effects / Q000627:therapeutic use*; D057915:Drug Substitution; D005260:Female; D006801:Humans; D053590:Interleukin 1 Receptor Antagonist Protein / Q000627:therapeutic use; D008297:Male; D008875:Middle Aged; D009220:Myositis / Q000175:diagnosis / Q000188:drug therapy* / Q000453:epidemiology / Q000276:immunology; D056687:Off-Label Use; D012042:Registries; D000069283:Rituximab / Q000627:therapeutic use; D013548:Sweden / Q000453:epidemiology; D013997:Time Factors; D016896:Treatment Outcome; D014409:Tumor Necrosis Factor-alpha / Q000037:antagonists & inhibitors / Q000276:immunology; D055815:Young Adult
chemical_list: D000893:Anti-Inflammatory Agents; D001688:Biological Products; D053590:Interleukin 1 Receptor Antagonist Protein; D014409:Tumor Necrosis Factor-alpha; D000069283:Rituximab