Abstract: 【Abstract】 Objective To investigate the clinical efficacy and safety of upadacitinib in the treatment of palmoplantar pustulosis that is refractory to or poorly controlled by conventional therapy and/or biological agents. Methods Clinical data were collected from 6 patients with palmoplantar pustulosis who were treated with upadacitinib at the outpatient department of Tianjin Medical University General Hospital from January 2023 to December 2023, and were retrospectively analyzed. Efficacy was evaluated by comparing the palmoplantar pustulosis area and severity index （PPPASI） scores and physician global assessment （PGA） scores in patients with palmoplantar pustulosis before and after the treatment. Adverse events were recorded during the treatment. Results Among the 6 patients with palmoplantar pustulosis, there was 1 male and 5 females, aged 47.22 ± 8.85 years. The patients were treated with oral upadacitinib at a dose of 15 mg/d or 30 mg/d. After 12 weeks of treatment and follow-up, the PPPASI scores decreased from 17.77 ± 10.34 points at baseline to 2.20 ± 1.73 points; the number of patients achieving PPPASI50, 75, 90 and 100 were 6, 6, 2 and 1, respectively, and 4 achieved PPPGA0/1. No severe adverse reactions occurred during the follow-up. Conclusion Upadacitinib may be a new option for refractory palmoplantar pustulosis, but its efficacy and safety still need to be evaluated in larger-sample studies.

Key words: Psoriasis, Arthritis, psoriatic, Janus kinase inhibitors, Upadacitinib, Therapy, Drug-related side effects and adverse reactions