By Lisa Seachrist

Washington Editor

Seeking funds to commercialize its lead antiviral product and bring two others to the clinic, ViroPharma Inc. filed a registration statement with the SEC to sell 3 million shares of common stock.

ViroPharma¿s stock (NASDAQ:VPHM) closed Wednesday at $23.125, up $1.937 a share. The Exton, Pa.-based company, which is under an SEC-imposed quiet period, estimated raising $70 million based on its closing price of $23.44 on Monday.

Following the close of this offering, the company will have nearly 14.6 million shares outstanding. Morgan Stanley Dean Witter, of New York, and US Bancorp Piper Jaffray Inc., of Minneapolis, are underwriting the proposed offering. ViroPharma has made 450,000 shares of common stock available for overallotments.

ViroPharma hopes to raise enough money to be ready to launch its most advanced product, pleconaril, as a treatment for viral meningitis should it gain FDA approval. In addition, the company is developing pleconaril as a treatment for viral respiratory infection (VRI), a severe form of the common cold.

The company began Phase III clinical trials of pleconaril for the treatment of viral meningitis in July 1998. In that study the company is testing whether 200 milligrams of pleconaril three times daily can reduce the duration of headaches associated with enteroviral meningitis in adults and adolescents. The company also has a pediatric component of this Phase III clinical program ¿ children are being treated three times per day with 2.5 milligrams of pleconaril for every kilogram they weigh.

Should pleconaril show positive results in this clinical trial and receive marketing clearance from FDA, ViroPharma will establish a specialty sales force of 50 to 70 people to market the drug to emergency medicine, infectious disease and pediatric infectious disease specialists, it said in SEC filings.

The company intends to take a different approach with pleconaril in VRI. A Phase III clinical study in VRI was initiated in September 1999. Adolescent and adult patients suffering from VRI are receiving 400 milligrams of the drug three times a day to see if the drug can reduce the length of the disease. In Phase II studies, pleconaril reduced by 3.5 days ¿ from 14 to 10.5 days ¿ the median time to complete symptom elimination.

The company is looking for a marketing partner for the drug in VRI since primary care physicians typically treat those patients. ViroPharma said it intends to have a marketing partner in place for the VRI indication of pleconaril by the end of 2000.

In addition to its clinical program with pleconaril, ViroPharma has two products ready to begin clinical testing. VO50406 is being developed for the treatment of hepatitis C. The company already is in discussions with potential marketing and development partners for this drug. ViroPharma is also developing VP14637 for the treatment of disease caused by respiratory syncytial virus and intends to market and develop that drug on its own. n