Introduction: Onychomycosis is a fungal infection, frequently caused by dermatophytes, that affects hand and foot nails. Infection rates in Western adult populations range from 2% to 14%, although up to 50% of people over 70 years of age may be affected. Prevalence of onychomycosis is also higher in immuno-compromised and patients with diseases that affect peripheral circulation, such as diabetes mellitus. The aim of the present study was to evaluate clinical efficacy of a nail acidifying solution vs. nail lacquer containing 5% amorolfine for the local treatment of mild to moderate nail onychomycosis.
Patients and Methods: 112 adults with confirmed onychomycosis (at least one great toenail) were randomized in this open, prospective, blinded trial. The acetic acid/ethyl lactate-based solution was brushed on twice-daily and the amorolfine lacquer applied and removed weekly for 168 days. Out of these 112 patients, a fully data analysis could be performed in 102 patients (53 acetic acid group and 49 amorolfine group, respectively). Clinical efficacy was evaluated at the following time points: day (D) D0 = baseline, D14, D28, D56, D112, and D168, respectively. All patients underwent microbiological testing at baseline and at the end of the treatment. Primary objective of this trial was the change in the percentage of healthy nail surface at study end.
Results: The percentage of healthy surface between baseline and D168 increased with 11.4% (± 17.0%) in the acid-based treated patient group and 5.2% (± 12.6%) in the amorolfine group respectively. The observed difference in increase of percentage of healthy surface after application of the acidifying solution was statistically significant (95% CI: 0.4; 12.1, p = 0.037) in comparison to the amorolfine group. Both treatments resulted in significant (p < 0.05) improvement after 168 days (vs. baseline) for nail dystrophy, discoloration, nail thickening, and healthy aspect but effects were more pronounced in the acetic acid group. Microbiological results and improved quality of life further confirmed clinical efficacy. Both treatments were well tolerated and appreciated for their properties and efficacy.
Conclusions: The present trial confirmed clinical performance of daily acidification of the nail, as reflected by 1) the superior increase of percentage of healthy nail surface when compared to amorolfine; 2) the overall improvement of other onychomycosis-related parameters; 3) the convenience and absence of significant side effects. These data indicate that acid/acid ester solutions can be a convenient, safe and equally effective alternative for the topical management of onychomycosis.