Anacor Pharmaceuticals announced positive results from a phase-1 clinical trial of AN2718, an investigational topical anti-fungal product candidate for the potential treatment of skin and nail infections. At various concentrations, AN2718 gel showed low irritation potential, leading investigators to conclude that application site reactions in future efficacy trials would be unlikely.

In this 21-day cumulative irritation study, AN2718 gel at 1.5 per cent, 2.5 per cent, 5.0 per cent and 7.5 per cent and AN2718 cream at 0.3 per cent and 1.0 per cent were compared to their respective vehicles. All doses of AN2718 gel, cream and vehicle were applied to the skin of normal volunteers for 21 days using semi-occlusive, adhesive patches. Application sites were then evaluated daily for signs of irritation. The irritation indices for all AN2718 doses were very low and comparable to vehicle.

"The absence of irritation seen in this study suggests that future efficacy and dosing studies will not be limited by tolerability," said Karl R Beutner, senior vice president and chief medical officer of Anacor Pharmaceuticals. "We look forward to initiating a phase-2 clinical trial later in the year to further evaluate the potential of AN2718."

AN2718 is a novel boron-containing small molecule that inhibits an essential protein synthesis enzyme, leucyl-transfer RNA synthetase, or LeuRS. This enzyme plays an essential role in fungal protein synthesis by attaching the leucine amino acid to transfer RNA, or tRNA.

Anacor is a biopharmaceutical company developing novel small molecule therapeutics derived from its boron chemistry platform.