P90 Adalimumab treatment for hidradenitis suppurativa: a retrospective analysis of demographics, patient characteristics and treatment outcomes for 107 patients from a tertiary dermatology centre
Authors: O’Connor Jane , Steyn Mia , Lakhan Manpreet , Ferguson Felicity , Malhomme Helena , Ayis Salma , Shah Aadarsh , Rashidghamat Ellie 
Published: June 2023

Hidradenitis suppurativa (HS) is a chronic inflammatory disease characterized by recurrent painful nodules, abscesses and sinus tracts in predominantly apocrine gland-bearing skin. Adalimumab is an antitumour necrosis factor biologic approved by the National Institute for Health and Care Excellence in June 2016 for the management of moderate-to-severe HS and is the only licensed biologic for HS. We conducted a retrospective review of patients attending our specialist HS service who were initiated on adalimumab. Demographics, Hurley stage, HS physician global assessment (HS-PGA), patient-reported psychosocial outcomes and reasons for treatment discontinuation were examined. The cohort comprised 57% females (53%). Seventy-four per cent of patients were overweight or obese (n = 80), with a mean weight of 90 kg. Seventy-eight per cent were current or ex-smokers (n = 83). Twelve per cent reported a positive family history of HS (n = 13). Patients had an average baseline Hurley score of 2.8, representing moderate-to-severe disease (Hurley stages 2–3) and a HS-PGA of 3.7 (3 = moderate and 4 = severe). Concomitant treatment with antibiotics and/or systemic therapy was required in 44% of patients (n = 48). Oral antibiotics (n = 30; 28%), Septrin® (n = 16; 15%) and acitretin (n = 10; 9%) were the three most commonly coprescribed medicines. Nineteen per cent of patients underwent a surgical procedure for HS during treatment. The average treatment duration of adalimumab was 22 months. Thirty-two per cent of patients discontinued. Reason(s) for discontinuation included primary failure (n = 13), side-effects (n = 12), malignancy (n = 3; lung adenocarcinoma, plasma cell myeloma, extramammary Paget disease), COVID-19 concerns (n = 3), loss to follow-up (n = 2), secondary failure (n = 2), personal stress (n = 1), serious infection (n = 1; tuberculosis) and pregnancy (n = 1). Statistically significant improvements in HS-PGA score at 16 weeks were demonstrated compared with baseline (3.7 vs. 2.8; P &lt; 0.001). Hurley score remained stable at these timepoints. Disease-related quality of life (Dermatology Life Quality Index) also significantly improved from 18.35 at baseline (reflecting severe impact) to 12.4 at 16 weeks (P &lt; 0.001). Statistically significant differences were also found for the following patient-reported outcomes at 16 weeks compared with baseline (rated out of 100): severity (67 vs. 52; P &lt; 0.013), odour (59 vs. 49; P = 0.008), discharge (64 vs. 46; P &lt; 0.001), pain (65 vs. 46; P &lt; 0.001) and fatigue (66 vs. 54; P = 0.006). Paired t-tests were used for all statistical analyses. In summary, adalimumab is an effective treatment for moderate-to-severe HS leading to clinical improvement in the HS-PGA scale and patient-reported outcomes. One-third of patients discontinued treatment due to a lack of response or side-effects. Adalimumab is often used in combination with other systemic therapies and surgery, reflecting the challenges of HS management.