Introduction: Guselkumab is a subcutaneously administered human monoclonal antibody, selectively blocking IL-23 through binding to its p19 subunit. It was initially approved for the treatment of patients with moderate-to-severe plaque-psoriasis who are candidates for systemic therapy or phototherapy. Pubmed and Embase databases were searched for publications, using the following search terms: psoriasis, psoriatic arthritis, guselkumab, risankizumab, tildrakizumab, p19, interleukin 23, guidelines, treatment recommendations, DISCOVER, ECLIPSE, and VOYAGE.

Areas covered: Accumulating evidence suggests that the IL-23/Th17 pathway is important in the pathogenesis of both psoriasis and psoriatic arthritis. Following a successful development program in psoriasis, guselkumab was evaluated for its efficacy and safety in psoriatic arthritis in a comprehensive clinical trial program, comprising one phase-2 study and two phase-3 studies (DISCOVER-1 and -2). Complementary data on pharmacokinetics and safety exist from pre-clinical experiments and pooled analyses from two long-term studies in psoriasis (VOYAGE-1 and -2). Based on the DISCOVER-1 and -2 data, guselkumab was approved by the FDA for the treatment of active psoriatic arthritis in 2020.

Expert opinion: Guselkumab is the first selective IL-23 inhibitor approved to treat adults with active psoriatic arthritis, broadening therapeutic options in the field through a novel mode of action.