title: Rate and Clinical Presentation of Macrophage Activation Syndrome in Patients With Systemic Juvenile Idiopathic Arthritis Treated With Canakinumab.
abstract: OBJECTIVE
  In pivotal trials, canakinumab has been shown to be effective in the treatment of systemic juvenile idiopathic arthritis (JIA), but reported adverse events have included macrophage activation syndrome (MAS). This study was undertaken to assess the impact of canakinumab on MAS incidence.
  
  
  METHODS
  An independent MAS Adjudication Committee (MASAC), consisting of 3 of the authors, was convened, and a search of databases from clinical studies of canakinumab treatment in systemic JIA was performed using MASAC-specified adverse event terms to identify potential MAS events. These were then adjudicated as "probable MAS," "possible MAS," or "MAS unlikely," using criteria developed by the MASAC. MAS rates were expressed as numbers of cases per 100 patient-years.
  
  
  RESULTS
  Of 72 potential MAS cases identified, 21 events (19 with canakinumab treatment; 2 with placebo treatment) in 19 patients were adjudicated as being probable MAS and 10 events in 9 patients as being possible MAS. Systemic JIA was well controlled in the majority of canakinumab-treated patients at the time of MAS. The time period between initiation of canakinumab treatment and onset of MAS ranged from 3 to 1,358 days (median 292 days). When the rates of probable MAS events were compared between canakinumab-treated patients (2.8 per 100 patient-years) and placebo-treated patients (7.7 per 100 patient-years), the difference was not significant (-4.9 [95% confidence interval -15.6, 5.9]). There were 3 deaths due to MAS-related complications (2 in patients receiving canakinumab; 1 in a patient receiving placebo); full recovery was reported in all other patients. Infections were the most common trigger of MAS, and the clinical features of MAS were not modified by canakinumab.
  
  
  CONCLUSIONS
  Canakinumab does not have a significant effect on MAS risk or its clinical features in patients with systemic JIA. Infections are the most common trigger, and MAS occurs even in patients whose systemic JIA is well controlled with this treatment.
authors: Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio.
authors: Alexei A
authors: AA
authors: Grom
authors: Children's Hospital at Montefiore, Bronx, New York.
authors: Norman T
authors: NT
authors: Ilowite
authors: Baylor Institute for Immunology Research, Dallas, Texas.
authors: Virginia
authors: V
authors: Pascual
authors: Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio.
authors: Hermine I
authors: HI
authors: Brunner
authors: Università di Genova and Istituto Giannina Gaslini, Genoa, Italy.
authors: Alberto
authors: A
authors: Martini
authors: Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio.
authors: Daniel
authors: D
authors: Lovell
authors: Istituto Giannina Gaslini, Genoa, Italy.
authors: Nicolino
authors: N
authors: Ruperto
authors: Novartis Pharmaceuticals Corporation, East Hanover, New Jersey.
authors: Karolynn
authors: K
authors: Leon
authors: Novartis Pharma AG, Basel, Switzerland.
authors: Karine
authors: K
authors: Lheritier
authors: Novartis Pharmaceuticals Corporation, East Hanover, New Jersey.
authors: Ken
authors: K
authors: Abrams
mesh_terms: D000293:Adolescent; D000911:Antibodies, Monoclonal / Q000009:adverse effects*; D061067:Antibodies, Monoclonal, Humanized; D018501:Antirheumatic Agents / Q000627:therapeutic use*; D001171:Arthritis, Juvenile / Q000188:drug therapy*; D002648:Child; D002675:Child, Preschool; D016208:Databases, Factual; D005260:Female; D006801:Humans; D007239:Infections / Q000453:epidemiology; D055501:Macrophage Activation Syndrome / Q000139:chemically induced* / Q000453:epidemiology; D008297:Male; D012307:Risk Factors; D055815:Young Adult
chemical_list: D000911:Antibodies, Monoclonal; D061067:Antibodies, Monoclonal, Humanized; D018501:Antirheumatic Agents; C541220:canakinumab