Anadys Pharmaceuticals Receives FDA Clearance of Phase II Protocol to Study ANA598...

Anadys Pharmaceuticals Receives FDA Clearance of Phase II Protocol to Study
ANA598 in Combination With Interferon-Alpha and Ribavirin in HCV Patients
ANA598 To Be Dosed for 12 Weeks in Triple Combination

SAN DIEGO, July 30 /PRNewswire-FirstCall/ -- Anadys Pharmaceuticals, Inc.
(Nasdaq: ANDS) today announced finalization of the protocol for the Company's
Phase II trial of ANA598 in combination with pegylated interferon-alpha and
ribavirin in hepatitis C patients. Allowance of the protocol has been
received from the United States Food and Drug Administration (FDA), and
patient dosing is expected to commence within the next several weeks.

In the Phase II study, naive genotype 1 patients will receive ANA598 or
placebo in combination with Pegasys(R) (peginterferon alfa-2a) and Copegus(R)
(ribavirin, USP) (a current standard of care, or SOC) for 12 weeks at dose
levels of 200 mg or 400 mg twice daily (bid), each with a loading dose of 800
mg bid on day one. After week 12, patients will continue to receive SOC.
Patients who achieve undetectable levels of virus at weeks 4 and 12 will be
randomized to stop all treatment at week 24 or 48. The primary endpoint of
the study is the proportion of patients with undetectable virus at week 12
(defined as complete Early Virological Response, or cEVR). Additional
endpoints include safety and tolerability as well as the proportion of
patients with undetectable virus at week 4 (defined as Rapid Virological
Response, or RVR), weeks 24 and 48, and 24 weeks after stopping all treatment
(defined as Sustained Virological Response, or SVR).

Ninety patients are planned to be enrolled in this study - thirty patients
receiving ANA598 and fifteen receiving placebo at each dose level. The study
will be conducted at a number of clinical sites in the United States. Anadys
expects to receive 28-day safety and response (RVR) data from the 200 mg dose
level by year-end and additional on-treatment safety and response data from
both cohorts during the first two quarters of 2010.

"ANA598 has demonstrated potent antiviral activity and good tolerability as a
single agent in Phase I, as well as preclinical properties indicative of
likely synergy when used clinically in combination regimens," said Steve
Worland, Ph.D., President and CEO of Anadys. "We are now in a position to
demonstrate the value of ANA598 when used in combination in a Phase II trial
to treat hepatitis C patients. This trial incorporates several attractive
features designed to further enhance the competitive position of ANA598,
including twelve weeks of triple combination treatment and a randomized
exploration of shortening the overall duration of HCV therapy in conjunction
with ANA598 treatment."

About ANA598

ANA598 is a non-nucleoside inhibitor of the HCV RNA polymerase. Anadys has
completed three Phase I clinical studies of ANA598 that have demonstrated
potent antiviral activity and good tolerability. In a monotherapy study in
naive genotype 1 patients, treatment with ANA598 for three days led to median
declines in viral load ranging from 2.4 to 2.9 log10 in three separate dose
groups. No patient at any dose level showed evidence of viral rebound while
on ANA598, and there were no serious adverse events.

Anadys has completed dosing in two long-term chronic toxicology studies of
ANA598 (26 weeks duration in rats and 39 weeks duration in monkeys). At the
13-week interim, the toxicology profile of ANA598 in both species was very
favorable. A preliminary assessment of the results from the 26-week study in
rats indicates a similar profile to that seen in rats at 13 weeks, in which
the only adverse finding was a marginal decrease in the rate of weight gain in
females at 1000 mg/kg, the highest dose tested. Complete results from both
studies, including 39-week data from the monkey study, are expected at the end
of the third quarter 2009.

Anadys has presented in vitro data supporting the use of ANA598 in combination
with interferon-alpha as well as with direct antivirals currently in
development. In particular, data has shown that ANA598 is synergistic in
vitro with interferon-alpha as well as representative HCV protease and
polymerase inhibitors. Furthermore, ANA598 retains full activity in vitro
against mutations conferring resistance to protease inhibitors, nucleoside
polymerase inhibitors and non-nucleoside polymerase inhibitors that act at
binding sites distinct from that of ANA598, and protease and nucleoside
polymerase inhibitors retain full activity against mutations conferring
resistance to ANA598.

ANA598 has received Fast Track Status from the FDA for the treatment of
chronic hepatitis C.

About Anadys

Anadys Pharmaceuticals, Inc. is a biopharmaceutical company dedicated to
improving patient care by developing novel medicines for the treatment of
hepatitis C. The Company believes hepatitis C represents a large unmet
medical need in which meaningful improvements in treatment outcomes may be
attainable with the introduction of new medicines. The Company is developing
ANA598, a non-nucleoside polymerase inhibitor for the treatment of hepatitis
C. The Company has also investigated the potential of ANA773, an oral,
small-molecule inducer of endogenous interferons that acts via the Toll-like
receptor 7, or TLR7, pathway in hepatitis C.

Safe Harbor Statement

Statements in this press release that are not strictly historical in nature
constitute "forward-looking statements." Such statements include, but are not
limited to, references to (i) Anadys' expectation that dosing in the ANA598
Phase II study will commence in the next several weeks; (ii) the ability for
patients in the ANA598 Phase II study to achieve undetectable levels of virus
at weeks 4 and 12 and to achieve SVR; (iii) Anadys' expectation that it will
receive 28-day data from the 200 mg dose level by year end and additional data
during the first two quarters of 2010; (iv) the antiviral and tolerability
profile of ANA598 seen to date, which may not be duplicated in the Phase II
study; (v) preclinical properties indicative of likely synergy when used
clinically in combination regimens; and (vi) the belief that certain features
of the Phase II protocol have the ability to further enhance the competitive
position of ANA598. Such forward-looking statements involve known and unknown
risks, uncertainties and other factors, which may cause Anadys' actual results
to be materially different from historical results or from any results
expressed or implied by such forward-looking statements. For example, the
results of preclinical and early clinical studies may not be predictive of
future results, and Anadys cannot provide any assurances that ANA598 will not
have unforeseen safety issues or will have favorable results in the planned
Phase II trial. In addition, Anadys' results may be affected by risks related
to competition from other biotechnology and pharmaceutical companies, its
effectiveness at managing its financial resources, its ability to enter into
collaborations around its product candidates, its ability to successfully
develop and market products, difficulties or delays in its preclinical studies
or clinical trials, difficulties or delays in manufacturing its clinical
trials materials, the scope and validity of patent protection for its product
candidates, regulatory developments involving its product candidates and its
ability to obtain additional funding to support its operations. Risk factors
that may cause actual results to differ are more fully discussed in Anadys'
SEC filings, including Anadys' Form 10-K for the year ended December 31, 2008
and Anadys' Current Report on Form 8-K filed on June 4, 2009. All
forward-looking statements are qualified in their entirety by this cautionary
statement. Anadys is providing this information as of this date and does not
undertake any obligation to update any forward-looking statements contained in
this document as a result of new information, future events or otherwise.

Pegasys(R) and Copegus(R) are registered trademarks of Hoffman-La Roche Inc.

SOURCE Anadys Pharmaceuticals, Inc.

investors, Amy Conrad of Anadys Pharmaceuticals, Inc., +1-858-530-3607,
aconrad@anadyspharma.com; or media, Ian Stone, ian.stone@russopartnersllc.com,
or David Schull, david.schull@russopartnersllc.com, both of Russo Partners,
LLC, +1-619-528-2220, for Anadys Pharmaceuticals, Inc.