Efficacy Assessment of a Topically Applied Nitric–Zinc Complex Solution for the Treatment of External Ano-genital Warts in 100 Patients

INTRODUCTION: External ano-genital warts (AGWs) due to human papilloma virus infection are the most common sexually transmitted ano-genital lesions of viral origin worldwide. Treatments include topical chemicals/drugs, excisional surgery, cryosurgery, electrosurgery and laser surgery. Nitric-zinc complex (NZC) is a new topically applied solution containing nitric acid, zinc, copper and organic acids that induces a caustic effect on condyloma. The objective of this study was to investigate the efficacy and tolerability of NZC in the treatment of AGWs. METHODS: Patients attending for AGWs between September 2016 and February 2018 were retrospectively studied. They received at least one NZC application for a maximum of four treatments (V0, V1, V2, V3) with average intervals of 25 days between sessions. Recurrences were evaluated at 3 and 6 months after clearance. RESULTS: One hundred patients (70 males, 30 females) with a mean age of 36.39 years were studied. The total number of AGWs diagnosed at the baseline visit (V0) in all patients was 418 with a mean of 4.18 AGWs per patient. A wart cure rate of 92% was observed in ≤ 4 treatment sessions (383 lesions cured at visit 4, V4, out of 418 lesions at baseline), with a cure rate of 49% with only one NZC application. Complete clearance was observed in 25, 52, 72 and 84% of patients at V1, V2, V3 and V4, respectively. Relapses were observed in 29% of patients at 3 months and in 5% at 6 months. Of note, patients with ≤ 5 AGWs at V0 showed better clearance results than patients with > 5 lesions (p < 0.05). The treatment was well tolerated by most patients. CONCLUSION: NZC has been demonstrated to be effective for AGWs after 1–4 treatment sessions, obtaining a good response from the first application. The better response in patients with fewer warts suggests that the earlier diagnosis is made and treatment started, the better the expected results. FUNDING: ISDIN.