By Kim Coghill

Washington Editor

Versicor Inc., a California-based company formed in 1995, said Thursday its lead product entered a pivotal Phase III trial.

V-Echinocandin (anidulafungin) is in Phase III trials in order to study the efficacy, safety and tolerability for the treatment of esophageal candidiasis, a fungal infection that causes serious morbidity in patients with compromised immune systems.

George Horner, CEO of Fremont-based Versicor, said the drug will undergo other Phase III trials and "we will make subsequent announcements throughout the year in terms of how we will prosecute our clinical programs. We see this as a first step in many announcements that you will hear this year."

He expects all the trials will be complete in about 18 months, with a targeted new drug application filing sometime around the end of 2002.

"When we went public [in August], one of the significant things we said was that we would bring this compound into Phase III clinical trials in the first quarter of this year. We've achieved that," Horner said.

Versicor grossed about $58 million by selling 4.6 million shares at a price of $11 per share in its IPO. (See BioWorld Today, Aug. 4, 2000.)

Thomas Dietz, a senior biotech analyst with Pacific Growth Equities in San Francisco, estimated that V-Echinocandin will be on the market by the end of 2003 and said its peak North American sales could reach $100 million annually, and worldwide sales $250 million.

Horner said Versicor owns the worldwide rights to V-Echinocandin and does not intend to partner the product.

V-Echinocandin is one of a new class of antifungal agents designed to kill fungi, rather than simply inhibit growth of the fungal cell (fungistatic) and may have a more favorable safety profile than currently available agents. This "killing effect" is an important benefit of V-Echinocandin, because the target patient population is immunosuppressed. Severely immunosuppressed patients may be more effectively treated with a therapy that is fungicidal rather than fungistatic, the company said.

Until recently, Dietz said two major classes of antifungal drugs - polyenes and azoles - were used to treat serious fungal infections. Those two classes of antifungals are limited because of side effects. In January, he said, Cancidas, a product of Merck & Co. Inc., of Whitehouse Station, N.J., was approved for the treatment of invasive aspergillosis in patients who do not respond to or cannot tolerate other antifungal therapies.

In in vitro studies that compared V-Echinocandin with caspofungin acetate (the active component of Merck's Cancidas), V-Echinocandin was found to be more potent in killing both candida and aspergillus, Dietz's research note said.

The 450 patients targeted to be enrolled in the Phase III trial in the United States and South Africa will be treated with a single daily intravenous infusion of V-Echinocandin for up to 21 days. In the first arm, patients will be treated with V-Echinocandin alone and, in the second arm, patients will be treated only with fluconazole, a currently available treatment for fungal infections.

The primary endpoint is endoscopy, and the study is powered to show non-inferiority (i.e., equivalence or superiority) of V-Echinocandin vs. fluconazole.

Patients enrolled in the Phase II trial were treated with single daily intravenous infusions of V-Echinocandin alone for up to 21 days. By the end of the treatment, more than 80 percent of 29 patients who were assessed by endoscopy (the primary endpoint) responded to treatment, with 17 patients experiencing complete responses (complete resolution). V-Echinocandin was well tolerated in the study.

Horner said Versicor has four classes of drugs, with V-Echinocandin, licensed from Eli Lilly and Co., of Indianapolis, the lead product.

V-Glycopeptide (dalbavancin), a novel antibiotic, is behind V-Echinocandin in development, and will be used for the treatment of Gram-positive infections.

The company also has research and development collaborations with Pharmacia Corp., of Peapack, N.J.; Novartis Pharma AG of Basel, Switzerland; and Biosearch Italia S.p.A. of Gerenzano, Italy.

Versicor's stock (NASDAQ:VERS) closed Thursday at $8, down 12.5 cents.