Gong X, Chen X, Kuligowski ME, et al. - Utilizing plasma concentrations of ruxolitinib from phase II and III studies, researchers sought to describe the pharmacokinetic (PK) profiles of ruxolitinib, a potent selective JAK1/JAK2 inhibitor, in patients treating their atopic dermatitis (also known as atopic eczema) with ruxolitinib cream. Three double-blind, vehicle-controlled studies in AD patients yielded pharmacokinetic data: phase II study with ruxolitinib cream 0.15%, 0.5%, or 1.5% once daily or 1.5% twice daily (BID), and two phase III studies with 0.75% or 1.5% BID. Plasma ruxolitinib concentrations after topical ruxolitinib cream treatment in patients with up to 20% BSA affected by AD are not expected to result in systemic plasma concentrations associated with adverse effects commonly associated with oral JAK inhibitors.