ABSTRACT: Hidradenitis suppurativa (HS) is a painful chronic skin disease characterized by abscesses, nodules, and tunnels in the skin. Adalimumab, a monoclonal antibody against tumor necrosis factor-α, is approved for the treatment of HS in Europe, the USA, and Japan. This multicenter, open-label, post-marketing, observational study (ClinicalTrials.gov: NCT03894956) evaluated the safety and effectiveness of adalimumab in routine clinical practice in Japan (March 2019-May 2021). Patients with HS were treated with s.c. doses of adalimumab according to the dosage described in the package insert. The primary end-point was safety (data cut-off, December 2020). Secondary end-points assessed effectiveness, including HS Clinical Response (HiSCR), skin pain, Dermatology Life Quality Index (DLQI), and C-reactive protein (CRP). Here, we report 12-week interim effectiveness results. A total of 84 eligible patients from 65 sites were enrolled; 83 patients were included in this analysis. Mean age was 42.0 years, mean body mass index was 26.9 kg/m2 , 78.3% of patients were male, 61.4% had Hurley stage III disease, 39.8% had a disease duration ≥10 years, and 7.2% had a family history of HS. The most common affected sites were the axilla (60.2%), buttocks (59.0%), and the inguinal and femoral regions (47.0%). Mean abscess and inflammatory nodule count was 13.0 (standard deviation, 12.0). Among patients with a comorbidity (57.8%), the most common were diabetes mellitus, hypertension, and chronic kidney disease. No patient reported a serious infection or any safety event of special interest. One patient died from a serious adverse event of cardiac failure unrelated to adalimumab. At week 12, 57.4% of patients achieved HiSCR, and significant reductions from baseline in skin pain, DLQI (both p < 0.0001), and CRP (p = 0.0029) were observed. These results support the administration of adalimumab as a well-tolerated and effective treatment for Japanese patients with HS in real-world clinical practice.
