Treatment of chronic erosive oral lichen planus with low concentrations of topical tacrolimus: an open prospective study.

Background: Chronic erosive oral lichen planus (EOLP) is a severe form of lichen of the buccal mucosa that is often resistant to systemic or topical therapies.

Objective: To evaluate the efficacy and safety of topical tacrolimus, 0.1 mg per 100 mL of water, in treating EOLP.

Design: Open-label, prospective, noncomparative study, with 6 months of treatment and 6 months of follow-up.

Setting: Dermatology department at a university hospital in Nice, France.

Patients: Ten patients with histologically proved EOLP that was refractory to treatment. Two patients were withdrawn because of noncompliance; findings in 8 were available for evaluation.

Interventions: Mouthwashes with tacrolimus, 0.1 mg per 100 mL of distilled water, 4 times daily for 6 months.

Main Outcome Measures: Efficacy was assessed using a calculated score that combined the intensity of spontaneous and meal-triggered pain and the surface area of erosions. Safety assessment included the monitoring of adverse effects, clinical laboratory values, and blood concentrations of tacrolimus.

Results: Among the 8 patients evaluated, 1 had no improvement and 7 were improved. The mean score decreased from 7.00 at baseline to 5.43 (a 22.43% decrease) at 1 month, 4.14 (a 40.86% decrease) at 2 months, 3.00 (a 57.14% decrease) at 3 months, 2.43 (a 65.29% decrease) at 4 months, 2.57 (a 63.29% decrease) at 5 months, and 3.43 (a 51.00% decrease) at 6 months. A decrease of symptoms was reported by the 7 responding patients as soon as the first month of treatment. No severe adverse effects were observed. All patients had whole-blood concentrations of tacrolimus below the detection limit of the assay (1.5 ng/mL) at all intervals. At 9 months, 6 patients had had a relapse within a mean of 38.6 days. At 12 months, all patients had had a relapse and required treatment with topical corticosteroids or systemic hydroxychloroquine sulfate.

Conclusion: Results of our study suggest a rapid and important palliating effect of low concentration of topical tacrolimus in distilled water in patients with EOLP.