title: Sodium oxybate therapy provides multidimensional improvement in fibromyalgia: results of an international phase 3 trial.
abstract: BACKGROUND
  Fibromyalgia is characterised by chronic musculoskeletal pain and multiple symptoms including fatigue, multidimensional function impairment, sleep disturbance and tenderness. Along with pain and fatigue, non-restorative sleep is a core symptom of fibromyalgia. Sodium oxybate (SXB) is thought to reduce non-restorative sleep abnormalities. This study evaluated effects of SXB on fibromyalgia-related pain and other symptoms.
  
  
  METHODS
  573 patients with fibromyalgia according to 1990 American College of Rheumatology criteria were enrolled at 108 centres in eight countries. Subjects were randomly assigned to placebo, SXB 4.5 g/night or SXB 6 g/night. The primary efficacy endpoint was the proportion of subjects with ≥30% reduction in pain visual analogue scale from baseline to treatment end. Other efficacy assessments included function, sleep quality, effect of sleep on function, fatigue, tenderness, health-related quality of life and subject's impression of change in overall wellbeing.
  
  
  RESULTS
  Significant improvements in pain, sleep and other symptoms associated with fibromyalgia were seen in SXB treated subjects compared with placebo. The proportion of subjects with ≥30% pain reduction was 42.0% for SXB4.5 g/night (p=0.002) and 51.4% for SXB6 g/night (p<0.001) versus 26.8% for placebo. Quality of sleep (Jenkins sleep scale) improved by 20% for SXB4.5 g/night (p≤0.001) and 25% for SXB6 g/night (p≤0.001) versus 0.5% for placebo. Adverse events with an incidence ≥5% and twice placebo were nausea, dizziness, vomiting, insomnia, anxiety, somnolence, fatigue, muscle spasms and peripheral oedema.
  
  
  CONCLUSIONS
  These results, combined with findings from previous phase 2 and 3 studies, provide supportive evidence that SXB therapy affords important benefits across multiple symptoms in subjects with fibromyalgia.
authors.affiliation: Rheumatologische Schwerpunktpraxis, Gräfelfing, Germany. dr.spaeth@mac.com
authors.forename: Michael
authors.initials: M
authors.lastname: Spaeth
authors.forename: Robert M
authors.initials: RM
authors.lastname: Bennett
authors.forename: Beverly A
authors.initials: BA
authors.lastname: Benson
authors.forename: Y Grace
authors.initials: YG
authors.lastname: Wang
authors.forename: Chinglin
authors.initials: C
authors.lastname: Lai
authors.forename: Ernest H
authors.initials: EH
authors.lastname: Choy
mesh_terms: D000759:Adjuvants, Anesthesia / Q000008:administration & dosage / Q000009:adverse effects; D000328:Adult; D005260:Female; D005356:Fibromyalgia / Q000188:drug therapy*; D005500:Follow-Up Studies; D006304:Health Status; D006801:Humans; D008297:Male; D008875:Middle Aged; D059352:Musculoskeletal Pain / Q000188:drug therapy*; D017060:Patient Satisfaction; D011788:Quality of Life; D012890:Sleep / Q000187:drug effects*; D012893:Sleep Wake Disorders / Q000188:drug therapy*; D012978:Sodium Oxybate / Q000008:administration & dosage* / Q000009:adverse effects
chemical_list: D000759:Adjuvants, Anesthesia; D012978:Sodium Oxybate