title: Novel assessment tools to evaluate clinical and laboratory responses in a subset of patients enrolled in the Rituximab in Myositis trial.
abstract: OBJECTIVE
  We aimed to assess changes in myositis core set measures and ancillary clinical and laboratory data from the National Institutes of Health's subset of patients enrolled in the Rituximab in Myositis trial.
  
  
  METHODS
  Eighteen patients (5 dermatomyositis, 8 polymyositis, 5 juvenile dermatomyositis) completed more in-depth testing of muscle strength and cutaneous assessments, patient-reported outcomes, and laboratory tests before and after administration of rituximab. Percentage change in individual measures and in the definitions of improvement (DOIs) and standardized response means were examined over 44 weeks.
  
  
  RESULTS
  Core set activity measures improved by 18-70% from weeks 0-44 and were sensitive to change. Fifteen patients met the DOI at week 44, 9 patients met a DOI 50% response, and 4 met a DOI 70% response. Muscle strength and function measures were more sensitive to change than cutaneous assessments. Constitutional, gastrointestinal, and pulmonary systems improved 44-70%. Patient-reported outcomes improved up to 28%. CD20+ B cells were depleted in the periphery, but B cell depletion was not associated with clinical improvement at week 16.
  
  
  CONCLUSIONS
  This subset of patients had high rates of clinical response to rituximab, similar to patients in the overall trial. Most measures were responsive, and muscle strength had a greater degree of change than cutaneous assessments. Several novel assessment tools, including measures of strength and function, extra-muscular organ activity, fatigue, and health-related quality of life, are promising for use in future myositis trials. Further study of B cell-depleting therapies in myositis, particularly in treatment-naïve patients, is warranted.
authors: Environmental Autoimmunity Group, Program of Clinical Research, NIEHS, NIH, Department of Health and Human Services (DHHS), Bethesda, MD, USA. riderl@mail.nih.gov.
authors: Lisa G
authors: LG
authors: Rider
authors: Adrienne L
authors: AL
authors: Yip
authors: Iren
authors: I
authors: Horkayne-Szakaly
authors: Rita
authors: R
authors: Volochayev
authors: Joseph A
authors: JA
authors: Shrader
authors: Maria L
authors: ML
authors: Turner
authors: Heidi H
authors: HH
authors: Kong
authors: Minal S
authors: MS
authors: Jain
authors: Anna V
authors: AV
authors: Jansen
authors: Chester V
authors: CV
authors: Oddis
authors: Thomas A
authors: TA
authors: Fleisher
authors: Frederick W
authors: FW
authors: Miller
mesh_terms: D000293:Adolescent; D000328:Adult; D000893:Anti-Inflammatory Agents / Q000627:therapeutic use*; D058846:Antibodies, Monoclonal, Murine-Derived / Q000627:therapeutic use*; D001402:B-Lymphocytes / Q000187:drug effects / Q000276:immunology; D015415:Biomarkers / Q000097:blood; D002648:Child; D005260:Female; D006305:Health Status Indicators; D006801:Humans; D008297:Male; D008875:Middle Aged; D053580:Muscle Strength / Q000187:drug effects; D009220:Myositis / Q000097:blood / Q000175:diagnosis / Q000188:drug therapy* / Q000503:physiopathology; D011237:Predictive Value of Tests; D020127:Recovery of Function; D012074:Remission Induction; D000069283:Rituximab; D012867:Skin / Q000187:drug effects / Q000473:pathology; D011795:Surveys and Questionnaires; D013997:Time Factors; D016896:Treatment Outcome
chemical_list: D000893:Anti-Inflammatory Agents; D058846:Antibodies, Monoclonal, Murine-Derived; D015415:Biomarkers; D000069283:Rituximab