OBJECTIVES: The Hidradenitis Suppurativa (HS) Symptom Daily Diary (HSSDD) and HS Symptom Questionnaire (HSSQ) item scores provide information on the HS-specific symptoms of patients. Here, clinically meaningful within-patient (CMWP) improvements and severity thresholds for individual item scores are determined.

METHODS: Pooled, blinded data from two identically designed randomised phase 3 trials (BE HEARD I&II [NCT04242446, NCT04242498]) of bimekizumab 320 mg every two/four weeks or placebo were used to estimate HSSDD and HSSQ thresholds in moderate to severe HS patients. The five HSSDD and four HSSQ items were ranked on an 11-point numeric rating scale (0–10); higher scores indicate higher symptomology level. Recall period was 24-hours and 7-days, respectively. Threshold analyses conducted on observed scores for all randomised patients with ≥1 non-missing item score at any scheduled assessment visit. Anchor- (Patient Global Impression of HS Severity [PGI-S-HS] or Severity of Skin Pain [PGI-S-SP]) and distribution-based analyses used to determine CMWP improvement thresholds. Receiver operating characteristic analyses, using PGI-S-HS or PGI-S-SP as anchors, used for severity thresholds.

RESULTS: 934 and 1,007 patients included for HSSDD and HSSQ-related analyses, respectively.

HSSDD: a 3- to 4-point decrease was identified as marked CMWP improvement for worst and average skin pain item scores; 2- to 3-point decrease for smell or odour, itch, and draining or oozing item scores.

HSSQ: a 4- to 5-point decrease was identified as marked CMWP improvement for skin pain item score; 3- to 4-point decrease for smell or odour and draining or oozing item scores; 3-point decrease for itch.

Severity thresholds for both HSSDD and HSSQ were identified, including HSSDD worst skin pain item: <1.67, ≥1.67–<4.00, ≥4.00–<5.50, ≥5.50–<7.17 and ≥7.17 for None, Mild, Moderate, Severe and Very Severe, respectively.

CONCLUSIONS: This analysis defined CMWP improvement and severity thresholds for HSSDD and HSSQ item scores, which can assess treatment efficacy and disease impacts in HS patients.