Stopping a biologic can trigger a painful pustular flare in psoriasis, and some patients are predictable

The edition in brief

Four studies for dermatologists. In 1,198 biologic withdrawal episodes in plaque psoriasis, 7.2% were followed by a distinct pustular flare — painful, diffuse erythema with pustules and swelling, mostly on the legs. Risk rose with family history, psoriatic arthritis, a previous such flare, repeated withdrawal-relapse cycles and slow initial response; the authors advise close monitoring and early resumption. In the ICONIC-ADVANCE 1 and 2 trials (1,505 adults), the oral IL-23 receptor-blocking peptide icotrokinra kept about 70 to 75% at clear or almost clear skin from week 24 to 52, and 85 to 90% of week-16 responders held their response. In children, risankizumab matched ustekinumab on most week-16 measures and doubled complete clearance (PASI100 40.7% vs 17.9%) in 82 randomised patients. Nemolizumab did not meet its primary itch endpoint in 258 haemodialysis patients with chronic kidney disease-associated pruritus (47.7% vs 32.4%, P = .07). The pearl: what to tell a psoriasis patient before a planned biologic pause.