In atopic dermatitis (AD), phosphodiesterase 4 (PDE4) inhibition reduces proinflammatory mediators and cytokines. Difamilast is a new selective PDE4 inhibitor. One recent research published in the British Journal of Dermatology has found out that difamilast, in 0·3% and 1% ointments are superior to vehicle and well tolerated in paediatric patients
H. Saeki and colleagues from the Department of Dermatology, Nippon Medical School, Tokyo, Japan conducted the present study to demonstrate the superiority of topical difamilast to vehicle in Japanese paediatric patients with atopic dermatitis.
The authors carried out a phase 3 randomised, double-blind, vehicle-controlled trial, which included patients aged 2–14 years with an Investigator Global Assessment (IGA) score of 2 or 3. These patients received difamilast 0·3% (n = 83), difamilast 1% (n = 85) or vehicle (n = 83) ointment twice daily for 4 weeks.
The study revealed that the primary endpoint was established as the success rate in IGA score at week 4 (percentage of patients with IGA score of 0 or 1 with improvement by at least 2 grades). The success rates in IGA score at week 4 were 44·6%, 47·1%, and 18·1% in the difamilast 0·3%, difamilast 1%, and vehicle groups, respectively.
Both, difamilast groups demonstrated significantly higher success rates in IGA score versus vehicle at week 4 (difamilast 0·3%, P = 0·0005; difamilast 1%, P < 0·0001). Regarding secondary endpoints, success rates in Eczema Area and Severity Index (EASI) 50, EASI 75 and EASI 90 at week 4 were significantly higher in difamilast 0·3% and 1% than those in vehicle.
Eczema Area and Severity Index score in difamilast 0·3% and 1% was significantly reduced compared with that of vehicle at week 1, and the significant difference between both difamilast and vehicle groups was maintained from week 1 through week 4. Most treatment-emergent adverse events were mild or moderate, and no serious events or deaths were reported.
Hence, it was concluded that difamilast 0·3% and 1% ointments are superior to vehicle and well tolerated in Japanese paediatric patients with atopic dermatitis.
doi:10.1111/bjd.20655