Atopic dermatitis, a chronic, pruritic skin disease, affects 10–30% of children and up to 14% of adults in developed countries. ATI-1777, a potent and selective Jak1/3 inhibitor, was designed with multiple sites of metabolism to deliver local efficacy in the skin and limit systemic exposure. In preclinical studies, ATI-1777 selectively inhibited Jak1/3 with limited systemic exposure and without any adverse effects.
The primary goal of this study was to assess the preliminary clinical efficacy of ATI-1777 topical solution in adults with moderate or severe atopic dermatitis.
ATI-1777-AD-201, a phase 2a, first-in-human, randomized, double-blind, vehicle-controlled, parallel-group study, evaluated the efficacy, safety, tolerability, and pharmacokinetics of ATI-1777 topical solution in 48 participants with atopic dermatitis over 4 weeks.
The primary endpoint was a reduction of a modified Eczema Area and Severity Index score from baseline.
Reduction was significantly greater in the ATI-1777–treated group on day 28 than in vehicle-treated group (percentage reduction from baseline = 74.45% [standard error = 6.455] and 41.43% [standard error = 6.189], respectively [ P < .001]). Average plasma concentrations of ATI-1777 were <5% of the half-maximal inhibitory concentration of ATI-1777 for inhibiting Jak1/3. No deaths or serious adverse events were reported.