Pharmacokinetics, Safety, and Skin Irritation and Sensitization Potential of Clascoterone Cream in Early‐Phase Clinical Study Participants

Clascoterone is an androgen receptor inhibitor approved for the treatment of acne vulgaris in patients 12 years of age and older. Here, we report results of 5 phase 1 studies that assessed the pharmacokinetics (PK), safety, and skin irritation and sensitization potential of clascoterone cream 1% in healthy participants and patients with acne. Studies CB-03-01/02 (EudraCT: 2007-005064-28) and CB-03-01/04 (n = 24 each) assessed PK in healthy participants. Study 171-7151-203 (n = 8) assessed steady-state PK in patients with acne. Studies CB-03-01/05 (n = 36) and CB-03-01/32 (n = 250) assessed skin irritation and sensitization potential, respectively, in healthy participants. Systemic exposure to clascoterone was low after repeated daily application for up to 42 days of treatment. Clascoterone was excreted in urine as conjugated esters at a ≤1% fraction of the administered dose. Adverse events and local skin reactions were generally mild/moderate and reversible. No clinically relevant changes were observed in laboratory tests and vital signs. Skin irritation and sensitization with clascoterone treatment were minimal. Phase 1 study findings supported low systemic absorption of clascoterone and a favorable safety profile after topical application of clascoterone cream 1%, with no evidence of irritation or sensitization.