Predicting the success of treating hidradenitis suppurativa with adalimumab

Hidradenitis suppurativa (HS) is a chronic skin disease affecting around 1% of the population and characterized by painful boil‐like lumps, cysts and scarring on skin folds. It has been linked to having increased amounts of ‘tumour necrosis factor alpha’ (TNF‐alpha), a protein in the body that causes inflammation. Adalimumab is a drug approved for HS that reduces the activity of TNF‐alpha. In this study, we have collected clinical (medical) data of HS patients treated with adalimumab from 21 Italian referral centers, with the aim of finding out whether any particular characteristic might predict their likelihood of responding to (having success with) this treatment. Clinical response to adalimumab, meaning how well the treatment works, was measured at week 16 and at week 52 after starting treatment with adalimumab, by means of the Hidradenitis Suppurativa Clinical Response (HiSCR), a recently introduced method of assessing response to treatment in HS. We found that patients who started adalimumab more than 10 years after their HS first started (‘onset’) had a twice higher risk of not responding at week 16, than patients who started adalimumab earlier. Furthermore, previous treatment with immunosuppressive / immunomodulating medicines was associated with a probability of not responding at week 52 that was approximately 1.8 times higher than in patients who had not been treated with those medicines. We confirmed the efficacy and safety of adalimumab in HS and hypothesized that an early use of this drug should be advised, to better control disease progression (called the “window of opportunity” concept). Furthermore, previous use of immunosuppressants could negatively influence the response to adalimumab. Linked Article:   Marzano et al. Br J Dermatol 2021; 184 :133–140.