Outcome and long-term treatment protocol for topical tacrolimus in oral lichen planus.

BACKGROUND AND OBJECTIVE Topical tacrolimus has been shown to be beneficial in the treatment of oral lichen planus (OLP). However, long-term effects and its optimal application protocol with gradual reduction have not been studied. Accordingly, we analysed the clinical response of OLP to tacrolimus in our daily clinical practice with a focus on the optimal long-term therapeutic scheme. METHODS Retrospective analysis of all consecutive patients diagnosed with OLP and treated with topical tacrolimus (0.03% oral rinse) in a clinical setting between 2015 and 2020. The objective clinical response was measured by a 4-point scale (complete remission, major remission, partial remission, no response), subjective impairment by a 3-point scale (severe, moderate, none). RESULTS Fifty-seven patients (74% women; median age: 66 years) were included. Fifty-six (98%) patients had prior treatment with topical steroids. After introduction of tacrolimus, objective remission (major or complete) was reached by 28%, 62%, 87% and 97% of patients after 3, 6, 12 and 24 months, respectively. Subjective remission was reported by 16%, 48%, 69% and 83% after 3, 6, 12 and 24 months of treatment, respectively. The treatment frequency could be gradually reduced from initially twice daily to once daily or less in 28%, 61%, 78% and 87% after 3, 6, 12 and 24 months, respectively. 41% of patients completely suspended the treatment at one point, but 67% of them experienced a relapse after a median time of 3.3 months. Four patients (7%) developped a squamous cell carcinoma (SCC) during the observation period. Otherwise, there were only few and minor side-effects. CONCLUSION Topical tacrolimus can be an effective second-line therapy for OLP refractory to potent topical corticosteroids. The therapy frequency can often be reduced during the maintenance period. Both signs of clinical activity and subjective impairment should guide therapy. Regular follow-up is necessary to recognize possible SCC