Safety and tolerability of tirbanibulin ointment 1% treatment on 100 cm2 of the face or scalp in patients with actinic keratosis: A phase 3 studyCapsule Summary

Background: Tirbanibulin is approved for actinic keratosis (AK) field treatment up to 25 cm2. However, AK often affects larger areas; thus, AK treatments for larger fields are needed. Objective: Evaluate the safety and tolerability of tirbanibulin when applied to a field of approximately 100 cm2. Methods: Phase 3, multicenter, open-label, single-arm study among adult patients having a treatment field on the face or balding scalp of approximately 100 cm2 with 4-12 AKs. Patients received tirbanibulin to cover the treatment field once daily (5 consecutive days). Safety was assessed by evaluating treatment emergent adverse events and tolerability by composite score of 6 local tolerability signs (LTS). Results: A total of 105 patients were included. The most common LTS were erythema (96.1%) and flaking/scaling (84.4%), being mostly mild-to-moderate severity, and resolved/returned to or close to baseline by Day 29. The only severe LTS were erythema (5.8%) and flaking/scaling (8.7%). Most frequent treatment emergent adverse events were application site pruritus (10.5%) and application site pain (8.6%). Mean total number of AKs decreased from 7.7 AKs at baseline to 1.8 AKs at Day 57. Mean percent of change (reduction) from baseline in lesion count was 77.8% at Day 57. Limitations: No control group. No long-term follow-up. Conclusion: Safety and tolerability profiles in patients treated with tirbanibulin up to 100 cm2 were consistent with those previously reported over smaller field. Tirbanibulin could be used on a larger field (>25 cm2).