Efficacy of granulocyte and monocyte adsorptive apheresis on skin and joint manifestations of palmoplantar pustulosis with pustulotic arthro‐osteitis: A multicentric, prospective, observational study

Abstract Granulocyte and monocyte adsorptive apheresis (GMA) selectively removes activated granulocytes and monocytes from the peripheral blood. In 2012, GMA was approved in Japan as a treatment for generalized pustular psoriasis and localized pustular psoriasis or palmoplantar pustulosis (PPP). Limited evidence from case reports and monocentric studies suggested that GMA is an effective treatment for skin and joint symptoms of PPP with pustulotic arthro‐osteitis (PAO). The present, prospective, observational study was performed at three dermatology departments in Japan to evaluate the efficacy and safety of GMA in patients with PPP with PAO. Between April 2017 and December 2020, two male and 12 female patients with PPP and PAO were enrolled. Their mean age, mean duration of skin manifestations, and mean duration of PAO symptoms was 52.8 years, 51.2 months, and 44.9 months, respectively. GMA was applied weekly over five sessions. The skin and joint symptoms were assessed at baseline, post‐GMA, and at the 3‐month follow‐up. A total of 12 patients completed five GMA sessions, and two patients discontinued the treatment because of adverse events. Thus, 12 patients were finally assessed post‐GMA, and 10 patients were assessed at the 3‐month follow‐up. The assessment of GMA efficacy demonstrated that the skin symptoms had remarkably improved and improved in 33.3% (4/12) and 70% (7/10) of the patients post‐GMA and at the 3‐month follow‐up, respectively. Furthermore, the joint symptoms had remarkably improved in 66.7% (8/12) and 60% (6/10) of the patients post‐GMA and at the 3‐month follow‐up, respectively. These results suggest that GMA is effective in treating the skin and joint symptoms of PPP with PAO.