Real-world safety and effectiveness of adalimumab in patients with hidradenitis suppurativa: A 52-week analysis of a postmarketing surveillance study in Japan

Adalimumab is a human monoclonal antibody against tumor necrosis factor-a that was approved in Japan for the treatment of hidradenitis suppurativa (HS), a chronic recurrent inflammatory skin disease. We report the results of the final analysis of the postmarketing surveillance (PMS) study (: NCT03894956), which evaluated the 52-week safety and efficacy of adalimumab for HS treatment in real-world clinical practice in Japan. This multicenter, prospective, open-label, observational study (March 2019 to May 2021) included patients with HS treated with subcutaneous adalimumab at doses following the package insert. The primary endpoint was safety, and the secondary endpoints were effectiveness, including HS clinical response (HiSCR), C-reactive protein (CRP), skin pain, and Dermatology Life Quality Index (DLQI). Of the 84 patients registered at 65 sites, 83 patients were included in the analyses. Adverse drug reactions (ADRs) were reported by 10 (12.0%) patients; two patients reported a serious ADR, including one patient with serious infection. Other safety events of special interest reported were liver disorder and dermatitis psoriasiform (one patient each). Almost all patients with ADRs were recovering or had recovered, except for one patient who experienced a serious ADR of liver disorder and died. At 12 weeks, 55.4% of patients achieved HiSCR; this increased to 60.5% and 62.8% at 24 and 52 weeks of adalimumab treatment, respectively. Significant reductions from baseline in CRP (P < 0.05), skin pain (P < 0.0001), and DLQI (P < 0.0001) were observed at all time points. The results from this PMS study demonstrated that long-term adalimumab treatment is well tolerated and effective in patients with HS in real-world clinical practice in Japan.