A Phase 1 Randomized, Placebo‐Controlled Trial With a Topical Inhibitor of Stearoyl‐Coenzyme A Desaturase 1 Under Occluded and Nonoccluded Conditions

Stearoyl‐coenzyme A desaturase 1 (SCD‐1) in sebaceous glands is a key enzyme in the synthesis of monounsaturated fatty acids essential for acne development. GSK1940029 gel, a novel SCD‐1 inhibitor, is being developed as a potential treatment for acne. To assess the irritation potential, pharmacokinetics (PK), and safety of topical GSK1940029 to the skin of healthy adults, two interdependent studies were conducted in parallel. Study 1 (n = 54) investigated the irritation potential of GSK1940029 (0.3% and 1%, occluded application) to allow for its application to larger surface areas in study 2 (n = 39), which investigated the safety, tolerability, and PK of GSK1940029 after single and repeat doses as occluded and nonoccluded applications. GSK1940029 was not a primary or cumulative irritant after 2 and 21 days of dosing in study 1. In study 2, single and repeat applications of GSK1940029 (0.1% to 1%) doses were well tolerated with little or no influence on AUC and C(max) under occluded or unoccluded conditions. Systemic exposure increased proportionally with surface area and was higher in occluded conditions. Design of these interdependent studies allowed for the assessment of the irritation potential for topical GSK1940029 in parallel with the investigation of PK and safety profiles.