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RIBAPHARM SUBMITS INVESTIGATIONAL NEW DRUG APPLICATION FOR HEPAVIR
B - A POTENTIAL NEW TREATMENT FOR THE MORE THAN 1.25 MILLION AMERICANS
CHRONICALLY INFECTED WITH THE HEPATITIS B VIRUS
Costa Mesa, CA - October 31, 2002 -- COSTA MESA, Calif.,
Oct 31, 2002 /PRNewswire-FirstCall via COMTEX/ -- Ribapharm Inc.
(NYSE: RNA) today announced that it has submitted an Investigational
New Drug (IND) application to the U.S. Food and Drug Administration
(FDA) to initiate Phase I clinical studies for Hepavir B in patients
with chronic hepatitis B.
"Ribapharm licensed the rights to develop and commercialize
Hepavir B from Metabasis Therapeutics Inc. in October 2001,"
said Johnson Y.N. Lau, MD, President and CEO of Ribapharm. "This
filing, one year after securing the rights to Hepavir B, underscores
the commitment of the development team and the strategic value of
the partnership between Ribapharm and Metabasis."
Metabasis discovered Hepavir B by applying its HepDirect(TM) prodrug
technology to a proven effective antiviral drug, PMEA. The HepDirect(TM)
technology is a proprietary platform technology discovered and developed
by Metabasis. In animal studies, Hepavir B is predominately converted
into the active moiety in the liver.
"Although Hepavir B is still in Preclinical Phase of development,
it represents an interesting prospect as the efficacy of the active
compound, PMEA, has been demonstrated to be active against both
wild type and drug resistant hepatitis B," said Robert Gish,
MD, Director of Hepatology and Liver Transplantation, California
Pacific Medical Center, San Francisco.
A Phase I clinical study on the safety of rising single doses of
Hepavir B in healthy volunteers was conducted in Europe in August
2002. The study showed that the incidence of treatment-emergent
adverse events associated with single oral doses of Hepavir B were
3 at 10 mg (6 subjects), 6 at 30 mg (12 subjects) and 0 at 60 mg
(6 subjects) versus 5 with placebo (4 subjects), indicating that
single oral doses of Hepavir B up to 60 mg is comparable to placebo
in healthy adult volunteers.
About Hepatitis B
Hepatitis B is a viral infection of the liver. The World Health
Organization (WHO) estimates that more than 350 million people worldwide
have chronic infections. In the United States, the Centers for Disease
Control and Prevention (CDC) estimate nearly 78,000 people each
year are newly infected with hepatitis B.
Chronic infection by the hepatitis B virus can lead to cirrhosis
and liver failure, as well as liver cancer in the more advanced
stages of the disease. The CDC estimates that death will occur in
15 to 25 percent of people chronically infected with hepatitis B.
Hepatitis B is highly infectious and occurs when blood or body
fluids from an infected person enters the body of a person who is
not immune or vaccinated. The virus is often spread through sexual
contact with an infected person. Contaminated needles used in intravenous
drug injections and blood transfusions from infected sources also
spread the virus to otherwise healthy individuals. Hepatitis B infection
can also be spread from mother to baby at birth.
Ribapharm is a biopharmaceutical company that seeks to discover,
develop, acquire and commercialize innovative products for the treatment
of significant unmet medical needs, principally in the antiviral
and anticancer areas.
THE "SAFE HARBOR" STATEMENT UNDER THE PRIVATE SECURITIES
LITIGATION REFORM ACT OF 1995. This press release contains forward-looking
statements that involve risk and uncertainties, including but not
limited to, projections of future sales, operating income, returns
on invested assets, regulatory approval processes, and other risks
detailed from time to time in the Company's Securities and Exchange
Commission filings.
SOURCE Ribapharm Inc.
CONTACT: Investors and Media, Joe Schepers of Ribapharm, +1-212-736-4488,
mobile, +1-973-951-6260, or jschepers@ribapharm.com (RNA)

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