Exhibit 99

         ViroPharma Announces the Sale of Additional Common Stock to
            American Home Products As Part of Hepatitis C Alliance


Exton, PA, October 24, 2000, -- ViroPharma Incorporated (Nasdaq: VPHM) today
announced that it has sold to American Home Products Corporation (NYSE: AHP) an
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additional 104,934 shares of ViroPharma's common stock for $3,000,000 as a
result of further progress made under the companies' hepatitis C virus
collaboration.  The price per share for the stock was based on a premium to a
trailing average price.  This sale is in addition to the sale of 96,059 shares
to American Home Products Corporation that ViroPharma announced on October 6,
2000.

"We are pleased with the progress that we have made in our hepatitis C
collaboration with Wyeth-Ayerst," said Michel de Rosen, ViroPharma's president
and chief executive officer.  "Our hepatitis C program is one of three product
candidate development programs that ViroPharma has advanced into human clinical
trials. We will continue to pursue aggressively the advancement of hepatitis C
product candidates for the treatment of this insidious disease."


In December 1999, ViroPharma and American Home Products Corporation, through its
pharmaceutical division, Wyeth-Ayerst, entered into an alliance to develop and
commercialize ViroPharma's lead small molecule antiviral drug candidates for
hepatitis C virus (HCV) and to discover, develop and commercialize additional
novel inhibitors of HCV.  In this transaction, American Home Products agreed to
purchase shares of ViroPharma's common stock at the time of completion of
certain product development stages.


ViroPharma Incorporated is committed to the commercialization, development and
discovery of antiviral pharmaceuticals.  The Company is focused on drug
development and discovery activities in viral diseases including viral
respiratory infection (VRI), hepatitis C and RSV disease.  ViroPharma's most
advanced product candidate, pleconaril, is clinical development for treatment of
picornavirus diseases, including late stage clinical trials for VRI.  ViroPharma
also has product candidates in clinical development for the treatment of
hepatitis C and RSV disease.


Wyeth-Ayerst Laboratories, a division of American Home Products Corporation
(NYSE:AHP), is a major research-oriented pharmaceutical company with leading
products in the areas of women's health care, cardiovascular therapies, central
nervous system drugs, anti-inflammatory agents, infectious disease, hemophilia,
oncology, vaccines, and generic pharmaceuticals. American Home Products
Corporation (NYSE:AHP) is one of the world's largest research-based
pharmaceutical and health care products companies.  It is a leader in the
discovery, development, manufacturing and marketing of prescription drugs and
over-the-counter medications.  It is also a leader in vaccines, biotechnology
and animal health care.


This press release contains forward-looking statements that involve a number of
risks and uncertainties, including those relating to ViroPharma's continuing
efforts to develop product candidates for the treatment of hepatitis C.  There
can be no assurance that ViroPharma's hepatitis C discovery and preclinical
development efforts will be successful, that clinical trials with product
candidates emerging from such efforts can be initiated on a timely basis, or at
all, or that any such trials can be successfully concluded.  Investigational
pharmaceutical products, such as ViroPharma's product candidates for hepatitis
C, require significant time and effort for research and development, laboratory
testing and clinical testing prior to regulatory approval and commercialization.
As a result, all of the activities described in this press release are subject
to risks and uncertainties.  Neither the FDA nor any other regulatory authority
has approved any of ViroPharma's product candidates for commercialization. There
can be no assurance that FDA or other regulatory authority approval for any
product candidate under development by ViroPharma will be granted on a timely
basis or at all.  Even if approved, there can be no assurance that such drug
candidates will achieve market acceptance.   These factors, and other factors
that could cause future results to differ materially from the expectations
expressed in this press release, include, but are not limited to, those
described in ViroPharma's most recent Registration Statement on Form S-3 filed
with the Securities and Exchange Commission.  The forward-looking statements
contained in this press release may become outdated over time. ViroPharma does
not assume any responsibility for updating any forward-looking statements.


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