ViroPharma Inc., which is developing drugs to treat diseases causedby RNA viruses, filed for an initial public offering (IPO) expected togross about $27 million.
The Malvern, Pa., company, which began operations in December1994, registered to sell 2.25 million shares at an expected price of$11 to $13 each. After the offering ViroPharma will have about 8.8million shares outstanding.
Many of the scientists and executives at ViroPharma worked atSterling Winthrop Research Institute or its affiliates before thatcompany was taken over by Paris-based Sanofi SA.
Initial development and discovery activities at ViroPharma arefocused on six RNA virus diseases: viral meningitis, "summer flu,"the common cold, influenza, hepatitis C and viral pneumonia. Themost advanced compound, pleconaril (VP 63843), is being developedfor three of the diseases.
The company said pleconaril is a potent, broad-spectrum, orallyactive inhibitor of the RNA viruses that cause viral meningitis,summer flu and the common cold. A Phase IIa study using a summerflu model demonstrated the drug was effective against all fiveendpoints evaluated. A Phase IIb study of pleconaril was started inJune in viral meningitis, and an intranasal formulation is inpreclinical tests for the common cold.
ViroPharma's strategy is to identify and advance inhibitors of theprocess of viral RNA uncoating and replication. For RNA viruses tocause disease they must replicate. Inhibiting replication, therefore,can prevent, limit or stop the disease, the company said.
ViroPharma said it has discovered and characterized RNA uncoatingand replication activities, identified critical molecular targets,developed high-throughput screening assays and discovered andoptimized small-molecule compounds through screening efforts.
The lead drug, pleconaril, the company said, inhibits enterovirus andrhinovirus replication by binding to a specific site inside the coatprotein of the virus. That prevents the release of the viral RNA insidethe cell and blocks the initiation of the replication process.
In preclinical studies the drug inhibited the cell culture replication of96 percent of the rhinoviruses and enteroviruses isolated from 332human patients. Orally administered pleconaril protected mice fromlethal infection by enteroviruses in three distinct animal modelsystems.
In April ViroPharma disclosed results from a double-blind, placebo-controlled Phase II study of pleconaril in 33 healthy volunteers, whowere injected with a enterovirus that caused a summer flu-like illness.Patients on the drug had symptoms reduced to near backgroundlevels, the company reported.
Daily nasal mucus weights of greater than 10 grams were collectedfrom 63 percent of placebo subjects vs. none in the drug-treatedgroup. On the peak day of symptoms half the placebo patients wereill compared to none in the treated group.
Last March ViroPharma and Chiroscience Ltd., of Cambridge, U.K.,began a collaboration to discover drugs that block replication ofRNA viruses. Chiroscience will use its combinatorial chemistry andrational drug design to generate compounds, which ViroPharma willscreen in its chemical and biological assays. The companies willshare rights to compounds identified for clinical development.
The company has an agreement with Sanofi to secure rights forpleconaril in the U.S. and Canada. It was discovered at Sanofi byscientists now at ViroPharma. The company also has a discovery anddevelopment agreement with Boehringer Ingelheim PharmaceuticalsInc., of Ridgefield, Conn., for one hepatitis C target. n
-- Jim Shrine
(c) 1997 American Health Consultants. All rights reserved.