Phase II study of KX2-391 ointment 1%, a novel field treatment for actinic keratosis, based on Src/tubulin polymerization inhibition

Background: KX2-391, a dual Src tyrosine kinase and tubulin polymerization inhibitor, inhibits the growth of human keratinocytes with IC50 of 32 nM and induces apoptosis in dividing cells. A phase I study demonstrated that KX2-391 ointment 1% reduced actinic keratosis (AK) lesion counts and was well tolerated following 3 or 5 days of treatment on the forearm. Aim: To determine the activity, safety and pharmacokinetics of KX2-391 ointment 1% (5 or 3 days) in adults with AK on the face or scalp.