Antifungal agent - R-126638

One of the most common human fungal skin infections is dermatocytosis. These widespread infections are caused by filamentous fungi, including Epidermophyton, Microsporum and Trichophyton species, and often prove difficult to treat.

Numerous different azole antifungal agents are already available, such as fluconazole, ketoconazole and itraconazole, and others are under development. These include R-126638, which is being investigated by US company Barrier Therapeutics as an oral treatment for dermatomycoses.¹

In one clinical trial, 10 patients with seborrhoeic dermatitis on the forehead caused by Malassezia yeasts were given 200mg of the drug.² Clinical evaluations were carried out before the drug was given, and again after three, seven and 28 days. It reduced the number of living yeasts significantly compared to baseline, and clinical parameters including erythema, itching and desquamation were substantially improved at days seven and 28, although not on the third day. There was no significant improvement in the severity of scaliness, and there was also no effect on sebum secretion.

A pilot trial in 20 patients with tinea pedis has also been carried out. Subjects were given 200mg of the drug once a day for three or five days.³ Six of the 10 patients given a three-day treatment had a negative KOH microscopic evaluation of scales from the border of active lesions at day 28, and seven of those given five days. All bar one of the 20 patients had a significant improvement in their condition after the 28 days.

It has also been given to 19 patients with pityriasis versicolor in 200mg/day doses as an open label study.⁴ After 10 days, 42% had negative KOH microscopic results, and all were mycologically cured by day 30. No serious adverse events occurred.