Ustekinumab in the treatment of palmoplantar pustulosis

Conflicts of interest: S.G., J.F. and S.D. have received travel grants from Janssen‐Cilag; U.M. has received honoraria as a speaker and advisor for Janssen‐Cilag/Centocor, the distributor and manufacturer of ustekinumab. No funding sources supported this work. Madam, Palmoplantar pustulosis (PPP) is a challenging disease for dermatologists for which no therapeutic standard has yet been defined.1 Acitretin and psoralen plus ultraviolet A (PUVA) are commonly used; however, virtually all the therapies used in plaque psoriasis and numerous experimental treatments have been tried in PPP with varying clinical response. This indicates the need for an efficacious systemic long‐term treatment for PPP. Ustekinumab is a fully human IgG1κ monoclonal antibody approved for the treatment of moderate to severe plaque psoriasis that inhibits the p40 subunit shared by interleukin (IL)‐12 and IL‐23. One mode of action is a decrease of IL‐17A‐ and IL‐17F‐producing T‐helper 17 cells.2 As IL‐17A and IL‐17F have been linked to tissue neutrophil recruitment,3 4–5 ustekinumab might be a therapeutic approach in diseases in which neutrophilic inflammation, such as in PPP, plays a role.6