The SILVER study. Efficacy of topical nitric-zinc complex solution in the treatment of resistant warts: A postmarketing evaluation.

The treatment of cutaneous viral warts caused by human papillomavirus (HPV) infection is often subject to local recurrence and a long clinical and treatment course. Our aim was to analyze real-life data on the treatment of difficult-to-treat warts from a multicenter postmarketing surveillance assessment on the efficacy, tolerability, and safety of a commercially available nitric-zinc complex solution (NZCS). Dermatologists from 14 Italian centers completed a questionnaire about their clinical experience on treatment of "difficult-to-treat" warts, which included warts in the plantar, periungual, anogenital and aesthetically sensitive areas. The questionnaire was designed to obtain detailed information on wart treatment and compare NZCS efficacy with previous treatments. Of 106 questionnaires returned, 83 reported NZCS use; 67 had previous treatments (23 cryotherapy, 2 electrocoagulation, 12 other topical application, and 30 combined treatment, such as laser, cryotherapy, and/or electrocoagulation). NZCS had superior efficacy to that of previous treatments (p < .0001), resulting in 84.1% with a full or partial clearance (vs. 44.8% for previous treatments), and had better local tolerability (p < .0001). NZCS showed better efficacy and tolerability than other previous wart treatments.