By Saabira Chaudhuri 
 

Anacor Pharmaceuticals Inc.'s (ANAC) shares tumbled early Tuesday despite what the biopharmaceutical company characterized as positive preliminary late-stage results for a study of its nail-fungus infection drug.

Shares--which surged shortly after the results were released--recently dropped 37% in premarket trading to $3.31 on what Wedbush analyst Gregory R. Wade said likely was a comparison with rival Valeant Pharmaceuticals International Inc.'s (VRX) competing product, efinaconazole.

A representative from Anacor wasn't immediately available to comment on the share declines.

Anacor's late-stage study showed that 6.5% of patients treated with its drug, tavaborole, met the primary endpoint of "complete cure." This compares with Valeant's two studies, which had the same primary endpoint and showed that 17.8% and 15.2% of subjects were completely cured.

Anacor's results mark the first of two Phase 3 trials of tavaborole; data from the second trial are expected in March.

Among the secondary endpoints, 26.1% of patients treated with tavaborole achieved a "completely clear" or "almost clear" nail, versus 9.3% in the vehicle-treated at week 52.

"We are pleased that tavaborole met all of the parameters outlined in our Special Protocol Assessment with the FDA with a high degree of statistical significance in this first Phase 3 trial," Anacor Chief Executive David Perry said in a statement. "With its high rates of 'completely clear' or 'almost clear' nails, high negative culture rates, demonstrated safety and ease of use, we believe tavaborole could offer significant advantages over currently approved treatments for onychomycosis."

Valeant published results in November from its two late-stage studies to treat onychomycosis, a common nail infection caused predominantly by dermatophyte fungi, resulting in nail destruction and deformity.

Valeant's shares closed Monday at $65.55 and were inactive premarket.

Write to Saabira Chaudhuri at saabira.chaudhuri@dowjones.com

Subscribe to WSJ: http://online.wsj.com?mod=djnwires

Valeant Pharma (NYSE:VRX)
Historical Stock Chart
From Mar 2024 to Apr 2024 Click Here for more Valeant Pharma Charts.
Valeant Pharma (NYSE:VRX)
Historical Stock Chart
From Apr 2023 to Apr 2024 Click Here for more Valeant Pharma Charts.