Immediate response to apremilast in patients with palmoplantar pustulosis: a retrospective pilot study.

Our study demonstrated that apremilast can effectively treat cutaneous manifestations and arthralgia in Japanese patients with PPP who had apparent pustules and/or clavicular-sternocostal arthralgia. Owing to the retrospective design of the study and a small sample size, placebo-controlled clinical trials with a larger number of patients are warranted to confirm the efficacy of apremilast for treatment of PPP.