A Study to Evaluate the Efficacy and Safety of Bimekizumab in Study Participants With Moderate to Severe Hidradenitis Suppurativa

Primary Outcome Measures

1. Percentage of Participants Achieving Clinical Response as Measured by Hidradenitis Suppurativa Clinical Response 50 (HiSCR50) at Week 16
   HiSCR50 was defined as at least a 50 percent (%) reduction from Baseline in the total abscess and inflammatory nodule (AN) count, with no increase from Baseline in abscess or draining tunnel count. Intermittent missing data are imputed using multiple imputation with Markov Chain Monte Carlo (MCMC) method followed by monotone regression for monotone missing data. Lesion counts were imputed and then dichotomized to obtain the response status. Participants who experienced an intercurrent event were treated as nonresponders following the intercurrent event. An intercurrent event was defined as receipt of systemic antibiotic rescue medication or discontinuation of study treatment due to an adverse event (AE) or lack of efficacy. Percentage of participants shown do not account for model effects using the logistic regression model.

Secondary Outcome Measures

1. Percentage of Participants Achieving Clinical Response as Measured by Hidradenitis Suppurativa Clinical Response 75 (HiSCR75) at Week 16
   HiSCR75 was defined as at least a 75% reduction from Baseline in the total AN count, with no increase from Baseline in abscess or draining tunnel count. Intermittent missing data were imputed using multiple imputation with MCMC method followed by monotone regression for monotone missing data. Lesion counts were imputed and then dichotomized to obtain the response status. Participants who experienced an intercurrent event were treated as nonresponders following the intercurrent event. An intercurrent event was defined as receipt of systemic antibiotic rescue medication or discontinuation of study treatment due to an AE or lack of efficacy. Percentage of participants shown do not account for model effects using the logistic regression model.
2. Absolute Change From Baseline in Dermatology Life Quality Index (DLQI) Total Score at Week 16
   The DLQI is a patient-reported questionnaire designed for use in adult participants with skin diseases and Hidradenitis Suppurativa (HS). The DLQI is a skin disease-specific questionnaire aimed at the evaluation of how symptoms and treatment affect patients' health related quality of life (HRQoL), with a recall period of 7 days. This instrument asks participants 10 questions about symptoms and feelings, daily activities, leisure, work and school, personal relationships, and treatment. The scoring of each answer for the DLQI is on a scale range of 0 (not at all) to 3 (very much). The DLQI total score was calculated by adding the score of each question. The maximum score is 30, and the minimum score is 0. The higher the score, the more quality of life is impaired. Participants who experienced an intercurrent event were treated as missing following the intercurrent event and imputed using the multiple imputation method for missing data.
3. Absolute Change From Baseline in Worst Skin Pain Score at Week 16
   Absolute change from Baseline in Worst Skin Pain score at Week 16 was assessed using the worst skin pain item in the Hidradenitis Suppurativa Symptom Daily Diary (HSSDD). Worst skin pain during the past 24 hours was assessed daily using an 11-point numeric rating scale (NRS) which ranges from 0 (no skin pain) to 10 (skin pain as bad as you can imagine). The worst skin pain score was derived from the weekly average of daily scores, defined as the sum of the scored item over the course of the study week divided by the number of days in which the item was completed, relative to each respective visit date. Intermittent missing data are imputed using multiple imputation with MCMC method followed by monotone regression for monotone missing data. Participants who experienced an intercurrent event were treated as missing following the intercurrent event and imputed using the multiple imputation method for missing data. Mean values shown do not account for model effects using the ANCOVA model.
4. Percentage of Participants Achieving Worst Skin Pain Response at Week 16
   Skin pain response at Week 16, as assessed by "worst skin pain" item in HSSDD, was defined as an improvement in weekly worst skin pain score of at least 3 points versus Baseline. Worst skin pain during the past 24 hours was assessed daily using an 11-point numeric rating scale (NRS) which ranges from 0 (no skin pain) to 10 (skin pain as bad as you can imagine). Worst skin pain score was derived from weekly average of daily scores (sum of scored item over study week/number of days in which item completed, relative to each respective visit). Intermittent missing data were imputed using multiple imputation with MCMC method followed by monotone regression for monotone missing data. Weekly pain scores were imputed and then dichotomized to obtain response status. Participants who experienced an intercurrent event were treated as non-responders following the intercurrent event. Percentage of participants shown do not account for model effects using logistic regression model.
5. Percentage of Participants With Treatment-emergent Adverse Events (TEAEs) During the Study
   An AE is any untoward medical occurrence in a patient or clinical study participant, temporally associated with the use of investigational medicinal product (IMP), whether or not considered related to the IMP. An AE could therefore be any unfavorable and unintended sign (including an abnormal laboratory finding), symptom, or disease (new or exacerbated) temporally associated with the use of IMP. TEAEs are defined as AEs that have a start date on or following the first dose of study treatment through the final dose of study treatment + 140 days (covering the 20-week Safety Follow-Up \[SFU\] period).
6. Percentage of Participants With Serious Treatment-emergent Adverse Events During the Study
   A serious adverse event (SAE) is defined as any untoward medical occurrence that, at any dose: Results in death; Is life-threatening, Requires inpatient hospitalization or prolongation of existing hospitalization; Results in persistent disability/incapacity; Is a congenital anomaly/birth defect; Important medical events. TEAEs are defined as AEs that have a start date on or following the first dose of study treatment through the final dose of study treatment + 140 days (covering the 20-week SFU period).
7. Percentage of Participants With Treatment-emergent Adverse Events (TEAEs) Leading to Withdrawal From the Study
   An AE is any untoward medical occurrence in a patient or clinical study participant, temporally associated with the use of IMP, whether or not considered related to the IMP. An AE could therefore be any unfavorable and unintended sign (including an abnormal laboratory finding), symptom, or disease (new or exacerbated) temporally associated with the use of IMP. TEAEs are defined as AEs that have a start date on or following the first dose of study treatment through the final dose of study treatment + 140 days (covering the 20-week SFU period). TEAEs leading to discontinuation of the study are reported.