A double-blind, randomized, placebo-controlled trial of oral isotretinoin in the treatment of recalcitrant facial flat warts

Background: Recalcitrant facial flat warts are caused by human papillomavirus and may persist for years despite treatment. Isotretinoin has demonstrated benefits in the treatment of recalcitrant, genital and common warts, but placebo-controlled trials have not been performed. Objective: To determine whether isotretinoin is safe and effective for recalcitrant facial flat warts. Methods: Isotretinoin 30 mg/day or placebo was administered to 16 and 15 patients, respectively, in double-blind, randomized fashion for 12 weeks. Cutaneous lesions were assessed and adverse events including serologic and ophthalmologic changes were recorded. It is considered that warts were recalcitrant if the patient was treated for at least 3 years with at least three of the following options: retinoids, 5-fluorouracil, imiquimod and cryotherapy using liquid nitrogen. Results: Each patient in the istotretinoin group showed complete clearance of all flat warts, while none of the patients in the placebo group showed any improvement (p = 0.0001). The most frequent adverse event was cheilitis. There were no statistically significant changes in the laboratory findings. Limitations: The study design does not permit complete blinding of the dermatologist who can easily recognize the adverse effects of isotretinoin. The clinical findings, however, were so dramatic that this would not have impacted the findings. Another limitation of the study is a lack of follow-up to assess for recurrence after the drug was discontinued. Conclusions: Isotretinoin is an effective treatment for recalcitrant flat facial warts with a well-known, manageable safety profile.