1% difamilast ointment safe, effective against atopic dermatitis

Difamilast ointment is superior to vehicle and can be a safe and effective option for the treatment of atopic dermatitis (AD), a recent study reports.

Researchers conducted a phase III, randomized, double-blinded trial of 364 patients, of whom 182 (mean age 32.1 years, 55.5 percent men) received a vehicle control while 182 (mean age 31.7 years, 52.7 percent men) were given 1% difamilast ointment. Treatments were given twice-daily for 4 weeks, after which the primary endpoint of success rate in investigator global assessment (IGA) was assessed.

Success, defined as an IGA score of 0 or 1, with improvement of at least two grades, was reported in 38.46 percent of the difamilast group, a significantly higher rate than the 12.64-percent success rate in the vehicle arm (difference, 25.93 percent; p<0.0001).

Notably, such superiority of difamilast was already apparent as early as week 1 (success rate, 10.99 percent vs 0.55 percent; difference, 10.45 percent; p<0.0001).

Difamilast likewise proved superior in terms of secondary endpoints, including the proportion of patients with ≥50-percent, ≥75-percent, and ≥90-percent improvements in overall score in the eczema area and severity index (EASI; p<0.001 for all).

In terms of safety, 1% difamilast was correlated with treatment-emergent adverse events (TEAEs) in 17.6 percent of participants, as opposed to 28.0 percent in the vehicle arm. TEAEs were mostly mild or moderate in intensity. Worsening AD was the most common side effect, which led to discontinuations in 3.8 percent and 11.5 percent of difamilast and vehicle participants, respectively.