Ciclopirox olamine, an interesting active ingredient against fungal nail infections?

Onychomycoses, more commonly known as nail fungus, are a common fungal condition primarily affecting the toes. They are responsible for thickening, yellowish or brownish discoloration, and sometimes progressive deformation of the nail plate. This condition, often seemingly benign at first glance, can nonetheless be persistent and substantially impair quality of life, particularly because of its visibility. Most fungal nail infections are caused by dermatophytes, especiallyTrichophyton rubrum, but other pathogens, such as yeasts, for example those of the genus Candida, may also be involved. Treatment of onychomycoses generally relies on oral and/or topical antifungal agents, such as the ciclopirox olamine.

If your nails show symptoms indicative of a fungal infection, don’t hesitate to seek advice from your pharmacist or physician so they can guide you to an appropriate treatment.

Among the topical antifungals available for treating nail mycoses, ciclopirox olamine stands out with a unique mode of action that may offer certain advantages over the limitations of conventional therapies. Unlike azoles or allylamines, which target ergosterol biosynthesis—a molecule present in most fungi that plays a role similar to human cholesterol—ciclopirox olamine acts by disrupting the intracellular homeostasis of fungi, particularly by chelating the metal cations essential to their metabolism, such as iron. This activity, both fungistatic and fungicidal, gives this compound a particularly broad antifungal spectrum. It is effective against dermatophytes, the primary agents responsible for onychomycosis, but also against yeasts Candida and molds, which are often involved in atypical or recalcitrant forms.

Another advantage of ciclopirox olamine is its strong ability to penetrate nail keratin and reach the deeper layers.

Several studies have investigated the effects of ciclopirox olamine onychomycosis. Notably, two parallel-group, double-blind clinical trials can be cited. The first involved 223 patients (ciclopirox olamine 8% group: 112; placebo group: 111) and the second 237 (ciclopirox olamine 8% group: 119; placebo group: 118). The treatment consisted of applying one of the formulations daily to affected toenails for 48 weeks, with clinical evaluations every month and mycological assessments every 3 months. At the end of the protocol, the mycological cure rates were significantly higher in the ciclopirox olamine group: 29% vs. 11% in the first study and 36% vs. 9% in the second. Although these figures remain modest, they confirm the superiority of ciclopirox olamine over placebo. Furthermore, the treatment was very well tolerated, with adverse events being rare, localized (erythema, irritation), and transient.

Another study confirmed these positive results. In this study, an 8% ciclopirox olamine formulation, designated P-3051, was compared with a placebo and a reference preparation, which also contained 8% ciclopirox olamine. The difference between the test solution and the reference lay in the enhanced affinity for keratin of the new formulation. In total, 467 patients with onychomycosis were divided into three groups to receive a daily application of P-3051, the reference lacquer, or a placebo for 48 weeks. An additional 12-week follow-up was then conducted to assess the stability of the outcomes.

The results demonstrate a superior cure rate for products containing ciclopirox olamine.