title: Rituximab treatment in patients with refractory inflammatory myopathies.
abstract: To assess the efficacy of rituximab on disease activity and muscle strength in patients with inflammatory myopathies refractory to conventional therapy. METHODS; Thirteen patients were treated with rituximab 1000 mg i.v., twice, with a 2-week interval and followed for a median of 27 months. Primary outcomes were disease activity measured by creatine phosphokinase (CPK), lactate dehydrogenase (LDH) levels and muscle strength measured by hand-held dynamometry and manual muscle testing (MMT). Secondary outcomes were improvement in secondary laboratory measures, global assessment of general health, disease activity and pain, CS dose, functional ability, health-related quality of life and safety. Retreatment with rituximab was conducted if disease activity relapsed. RESULTS; The median levels of CPK and LDH were significantly reduced by 93.2 and 39.8%, respectively, compared with baseline after 34.6 months. The median muscle strength measured by hand-held dynamometry was significantly improved by 21.5% after 24 months. The median increase in muscle strength measured with MMT was 7.0% after 24 months of follow-up, although this did not reach statistical significance. Secondary outcomes improved as well. CONCLUSION; Rituximab is an effective treatment in refractory inflammatory myopathies, showing a decrease in CPK and LDH, an increase in muscle strength and improvement in scores of disease activity, general health, functional ability and health related quality of life with sustained effect during a median of 27.1 months of follow-up.
authors.affiliation: Department of Rheumatology, Radboud University Nijmegen Medical Centre, HB Nijmegen, The Netherlands. e.mahler@reuma.umcn.nl
authors.forename: Elien A M
authors.initials: EA
authors.lastname: Mahler
authors.forename: Marlies
authors.initials: M
authors.lastname: Blom
authors.forename: Nicol C
authors.initials: NC
authors.lastname: Voermans
authors.forename: Baziel G M
authors.initials: BG
authors.lastname: van Engelen
authors.forename: Piet L C M
authors.initials: PL
authors.lastname: van Riel
authors.forename: Madelon C
authors.initials: MC
authors.lastname: Vonk
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D058846:Antibodies, Monoclonal, Murine-Derived / Q000008:administration & dosage* / Q000009:adverse effects; D018501:Antirheumatic Agents / Q000008:administration & dosage* / Q000009:adverse effects; D003402:Creatine Kinase / Q000097:blood; D003882:Dermatomyositis / Q000188:drug therapy*; D004351:Drug Resistance; D005260:Female; D018737:Hand Strength; D006801:Humans; D007262:Infusions, Intravenous; D007770:L-Lactate Dehydrogenase / Q000097:blood; D008297:Male; D008875:Middle Aged; D053580:Muscle Strength / Q000187:drug effects; D018482:Muscle, Skeletal / Q000187:drug effects; D017285:Polymyositis / Q000188:drug therapy* / Q000503:physiopathology; D011788:Quality of Life; D012008:Recurrence; D019233:Retreatment; D000069283:Rituximab; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D058846:Antibodies, Monoclonal, Murine-Derived; D018501:Antirheumatic Agents; D000069283:Rituximab; D007770:L-Lactate Dehydrogenase; D003402:Creatine Kinase