ZADAXIN Adds Benefit to Pegylated Interferon for HCV Non-Responders;
Hepatitis C Patients Who Failed Prior Therapy Responding to ZADAXIN


SAN MATEO, Calif.--(BUSINESS WIRE)--Nov. 4, 2002--ZADAXIN(R) in combination
with pegylated interferon advanced in its effort to be part of the first
approved hepatitis C therapy for non-responders. Close to half of all
patients fail to respond to initial treatment with currently available
therapies and become non-responders. Today, SciClone Pharmaceuticals, Inc.
(Nasdaq:SCLN) reported that ZADAXIN in combination with pegylated interferon
alpha increased the early virologic response (EVR) rates up to 36% in
hepatitis C patients who had failed prior therapy. Complete data from a
twelve week dose ranging study showed that groups of non-responders treated
with ZADAXIN combination therapy reported positive dose related EVR rates
ranging from 20 to 36%. EVR is suggested to be an early indicator of
sustained response, and non-responders seldom have a sustained response to
re-treatment.

The results of this dose ranging study were presented today at the annual
meeting of the American Association for the Study of Liver Disease (AASLD) by
a team lead by Dr. Adrian Di Bisceglie of Saint Louis University School of
Medicine. Dr. Di Bisceglie concluded, "These data suggest that ZADAXIN in
combination with pegylated interferon may be able to treat a large subset of
hepatitis C patients that have been extremely difficult to treat in the past
-- non-responders infected with hepatitis C genotype 1. ZADAXIN was well
tolerated with no obvious side effects."

Dr. Eduardo Martins, Medical Director of SciClone Pharmaceuticals, commented,
"These data add to our belief that ZADAXIN has the potential to offer new,
safer and better therapy options for hepatitis C patients. Twelve week EVR
data has been proposed by hepatologists to be a predictor of patients that
may or may not respond to pegylated interferon therapy. Significantly, the
twelve week data from this dose ranging study clearly show ZADAXIN's ability
to add to the antiviral effects of pegylated interferon and improve response
rates in the treatment of some of the most difficult to treat hepatitis C
patients, those who have already failed to respond to prior therapy. Based on
these results, we are optimistic about the outcome of the two phase 3
hepatitis C clinical trials we are conducting."

Close to half of all hepatitis C patients fail to respond to the standard
therapy of pegylated interferon plus ribavirin. More dramatically, an
estimated two million hepatitis C carriers in the
U.S. are infected with a
high viral load of genotype 1 virus and are the most difficult group of
patients to treat. In comparison to the general hepatitis C patient
population, 70% of these patients fail to respond to standard therapy.

All 31 hepatitis C patients in the dose ranging study had a high viral load
of genotype 1 virus, 27 having failed previous treatment with interferon plus
ribavirin and four having failed with interferon alone. Patients were
randomized into three groups to receive 180 mcg/week of pegylated interferon
alfa-2a plus one of three different bi-weekly doses of ZADAXIN
. Observation
at the end of 12 weeks of therapy showed that EVR (measured by negative or a
greater than 2 log reduction in hepatitis C viral RNA) increased with higher
doses of ZADAXIN. The groups receiving 0.8 mg, 1.6 mg and 3.2 mg doses of
ZADAXIN in combination therapy reported EVR rates of 20%, 30% and 36%,
respectively. Based on extensive previous ZADAXIN clinical data and
commercial experience, SciClone's two
U.S. phase 3 hepatitis C clinical
trials are using the 1.6 mg twice weekly dose.

About SciClone's Phase 3 Hepatitis C Trials

SciClone's phase 3 hepatitis C clinical trials are currently enrolling 1,000
non-responders at multiple sites throughout the
U.S. During these trials,
patients will be randomized to receive either ZADAXIN plus pegylated
interferon or placebo plus pegylated interferon for a period of 12 months,
followed by a six-month observation period. F. Hoffmann LaRoche has provided
Pegasys brand pegylated interferon alfa-2a for these trials. Additional
information can be found at www.sciclone.com.

About SciClone

SciClone Pharmaceuticals is a biopharmaceutical company primarily focused on
the development of Immune System Enhancers. Its lead product ZADAXIN is in
two phase 3 hepatitis C clinical trials in the
U.S., a phase 3 hepatitis B
clinical trial in
Japan, a phase 2 malignant melanoma clinical trial in
Europe, and two phase 2 liver cancer clinical trials in the U.S.

ZADAXIN has been approved for sale by the ministries of health in over 30
countries and is marketed in China and selected other countries outside the
U.S. ZADAXIN has been administered to more than 10,000 patients in both
clinical and commercial use, alone and in combination with anti-viral and
anti-cancer drugs, without producing any reported ZADAXIN related significant
side effects or toxicities.

SciClone's strategic goal is to become a principal worldwide provider of
Immune System Enhancers (ISEs) both as monotherapies and as critical
components of combination drug therapies for infectious diseases and cancer.
In addition to ZADAXIN, SciClone's drug development opportunities include
SCV-07, a potentially orally available ISE, and products to address the
protein-based disorder that causes cystic fibrosis.

The information in this press release contains forward-looking statements
including expectations and beliefs regarding the outcome of SciClone's phase
3 hepatitis C clinical trials, the effectiveness of ZADAXIN in treating
hepatitis C patients and SciClone's ability to obtain regulatory approvals
for ZADAXIN. Words such as "expects," "plans," "believe," "may," "will,"
"anticipated," "intended" and variations of these words or similar
expressions are intended to identify forward-looking statements. In addition,
any statements that refer to expectations, projections or other
characterizations of future events or circumstances, including any underlying
assumptions, are forward-looking statements. These statements are not
guarantees of future performance and are subject to risks, uncertainties and
assumptions that are difficult to predict. Therefore, our actual results
could differ materially and adversely from those expressed in any
forward-looking statements as a result of various factors, including the fact
that results from studies with a limited group of patients may not be
predictive of the results of larger studies, EVR may not be predictive of the
achievement of the endpoint of the hepatitis C clinical trial, our ability to
enroll a sufficient number of eligible patients in the hepatitis C clinical
trials to yield statistically significant results, the speed with which
patients are enrolled in the hepatitis C clinical trials, maintenance of the
sufficiency and eligibility of the enrolled patient population, unexpected
adverse results to patients and the statistical significance of data obtained
from the clinical trials, the regulatory approval process, future actions of
the Food and Drug Administration and other events that could prolong the
clinical trials or result in unanticipated expense, as well as other risks
and uncertainties described in SciClone's filings with the Securities and
Exchange Commission.

CONTACT:

SciClone Pharmaceuticals, Inc.

Richard A. Waldron, 650/358-3437 (CFO)

SOURCE: SciClone Pharmaceuticals, Inc.

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11/04/2002 08:00 EASTERN