Evaluating the efficacy of 100% trichloroacetic acid needling in the treatment of palmoplantar warts

Towards Formulation of Highly Acidic Active Ingredients: Development of Clinically Effective Concentrated Trichloroacetic Acid Gel for Wart Management

Common warts are benign skin lesions caused by the human papillomavirus. Although they are usually not harmful, they can cause pain, depending on their location. While many modalities are available for treatment of warts, none is a gold standard, and many are not affordable and/or have suboptimal outcomes. Trichloroacetic acid (TCA) is a chemical tissue-destroying agent used as a highly concentrated solution for wart management. While available and efficient, it is difficult to handle as the solution spreads to tissue surrounding the wart causing pain and burning. Hence, we developed a new polymer-based gel of high TCA content (100% w/v). Gels were formed successfully as hydroxyethyl cellulose (HEC) and chitosan were used to impart viscosity and bioadhesion. Formulae of different concentrations were tested for their physical properties, and the optimal formulation was selected for clinical evaluation. A combination of 3% HEC and 2% chitosan provided optimal viscosity and limited water content and have acceptable stability. The efficacy and safety of the biweekly application of TCA gel were evaluated in 30 patients. The clinical study revealed gel's efficacy and tolerability; half of the patients showed a complete cure, and 90% showed improvement within 6 weeks. Only 10-12% of the patients reported side effects. In summary, transforming TCA solution into a gel enabled its application and handling in a practical manner by physicians and patients alike, while maintaining its efficacy as a tissue-destroying agent. Moreover, it is economic and easy to apply, rendering it a promising formulation for similar conditions requiring controlled tissue ablation.

Skin needling with 100% trichloroacetic acid vs. needling with bleomycin in the treatment of recalcitrant cutaneous warts

The treatment of warts has always been a challenging prospect for dermatologists. In some cases, these warts can become resistant or recalcitrant to treatment. Although a plethora of therapeutic and destructive options is available for wart management, to date no treatment has been found to be completely effective because none of the agents induce specific antiviral immunity. We conducted a study to evaluate the efficacy and safety of skin needling with topical 100% trichloroacetic acid (TCA) against the same type of skin needling with bleomycin in patients with recalcitrant cutaneous warts. In total, 33 (63.5%) patients in the TCA group and 35 (81.4%) in the bleomycin group had complete clearance of all the warts, which was not statistically significant (P = 0.13). There was also no statistically significant difference between the treated and untreated warts in the bleomycin group, whereas in the TCA group there was a significantly higher response rate in the treated warts. The most common adverse event (AE) in both groups was transient procedure site pain. We found that the use of needling plus TCA leads to a faster resolution of warts compared with needling plus bleomycin, with a comparable safety profile. Additionally, we found that TCA is superior to bleomycin for management of multiple warts. However, needling with either TCA or bleomycin has excellent and fairly comparable efficacy, and these methods should be used for the management of multiple or recalcitrant warts, as they have minimal AEs and recurrence rates.