Factors Influencing the Efficacy of Topical Tirbanibulin in Pigmented and Non-Pigmented Actinic Keratosis: Preliminary Results from an Ambispective Cohort Study

Background: Actinic cheilitis (AC) is a chronic inflammatory condition that is caused by excessive exposure to ultraviolet radiation from sunlight with an increased risk of developing invasive squamous cell carcinoma.There are currently no approved topical treatments.The aim of this study was to evaluate the efficacy and tolerability of tirbanibulin as a topical treatment for AC.Methods: Twenty patients with AC diagnosed with optical coherence tomography (OCT) were treated with topical Tirbanibulin once daily for five days.The follow up included clinical visits at seven, 14 and 56 days.Imaging with OCT was performed on day 1 to diagnose AC and on day 56 to assess healing.The subject's selfassessment score, oral health DLQI and local skin reaction score were analyzed at each visit to assess potential side effects.Results: Twenty patients (10 female, 10 male), were included in the study.Twelve patients (60%) showed complete remission and eight patients (40%) showed partial remission of their AC at day 56.Among the patients with partial remission, the reduction in area of AC was >75% in two patients, 50 -75% in five patients and <50% in one patient.The local skin reaction score at day 7 showed in 50% a mild reaction, in 45% a moderate reaction and in 5% a marked reaction like erythema, swelling, crusts, flaking, vesicles/pustules and erosion/ulceration.There were no severe or systemic adverse events.There were no treatment discontinuations.The oral health DLQI improved significantly between baseline and follow-up (6 vs. 3, p= 0.032).Conclusions: Topical treatment with Tirbanibulin may be an effective and well-tolerated option for the treatment of AC, although further investigation including long-term follow-up need to be performed.