title: Assessing the validity, responsiveness and meaningfulness of the Hidradenitis Suppurativa Clinical Response (HiSCR) as the clinical endpoint for hidradenitis suppurativa treatment.
abstract: BACKGROUND
  Quantification of disease severity supports the development of evidence-based treatments. Assessments to capture clinical improvement in hidradenitis suppurativa (HS) can be improved.
  
  
  OBJECTIVE
  This study aimed to validate the Hidradenitis Suppurativa Clinical Response (HiSCR), which is defined as a ≥ 50% reduction in inflammatory lesion count (sum of abscesses and inflammatory nodules, AN), and no increase in abscesses or draining fistulas in HS when compared with baseline as a meaningful clinical endpoint for HS treatment.
  
  
  METHODS
  Patients with ≥ 3 ANs at baseline in a Phase II adalimumab trial for HS were included for analysis. HiSCR achievers vs. nonachievers were assessed at week 16 and week 52. Criteria measures included physician-rated assessments [Hurley stage, modified Sartorius score (MSS), and HS Physician's Global Assessment] and patient-reported outcomes (PROs: visual analogue pain scale, Dermatology Life Quality Index, and Work Productivity and Activity Impairment questionnaire). Test-retest reliability, convergent validity, responsiveness and predictive validity of HiSCR, and its meaningfulness to patients were assessed.
  
  
  RESULTS
  Among 138 eligible study participants, the majority were female (69·6%) with a mean age of 36·7 years. The mean (median) MSS was 125·2 (85·5) at baseline. Test-retest reliability of the AN count was 0·91. HiSCR was significantly correlated with improvements in all physician-rated and PRO measures (Spearman's rho between -0·61 and -0·27, all P < 0·001). Improvements of all PROs in HiSCR achievers exceeded the respective meaningful improvement thresholds.
  
  
  CONCLUSIONS
  In patients with HS with ≥ 3 ANs, HiSCR achievers had significant improvements in physician-rated and patient-reported HS disease severity and impact. HiSCR is a valid and meaningful endpoint for assessing HS treatment effectiveness in controlling inflammatory manifestations in this population.
authors.affiliation: Department of Dermatology, Harvard Medical School, Boston, MA, U.S.A.
authors.forename: A B
authors.initials: AB
authors.lastname: Kimball
authors.forename: G B E
authors.initials: GB
authors.lastname: Jemec
authors.forename: M
authors.initials: M
authors.lastname: Yang
authors.forename: A
authors.initials: A
authors.lastname: Kageleiry
authors.forename: J E
authors.initials: JE
authors.lastname: Signorovitch
authors.forename: M M
authors.initials: MM
authors.lastname: Okun
authors.forename: Y
authors.initials: Y
authors.lastname: Gu
authors.forename: K
authors.initials: K
authors.lastname: Wang
authors.forename: P
authors.initials: P
authors.lastname: Mulani
authors.forename: M
authors.initials: M
authors.lastname: Sundaram
mesh_terms: D000068879:Adalimumab; D000328:Adult; D000893:Anti-Inflammatory Agents / Q000627:therapeutic use*; D061067:Antibodies, Monoclonal, Humanized / Q000627:therapeutic use*; D005260:Female; D017497:Hidradenitis Suppurativa / Q000188:drug therapy*; D006801:Humans; D008297:Male; D010146:Pain / Q000517:prevention & control; D010147:Pain Measurement; D011788:Quality of Life; D015203:Reproducibility of Results; D012720:Severity of Illness Index; D016896:Treatment Outcome
chemical_list: D000893:Anti-Inflammatory Agents; D061067:Antibodies, Monoclonal, Humanized; D000068879:Adalimumab