Idenix Pharmaceuticals Provides Update on Hepatitis C Pipeline at JP Morgan Healthcare...

Idenix Pharmaceuticals Provides Update on Hepatitis C Pipeline at JP Morgan
Healthcare Conference

SAN FRANCISCO, Jan. 7 /PRNewswire-FirstCall/ -- Idenix Pharmaceuticals,
Inc. (Nasdaq: IDIX), a biopharmaceutical company engaged in the discovery and
development of drugs for the treatment of human viral and other infectious
diseases, today announced an update on the company's HCV pipeline, including
promising second-generation polymerase and protease inhibitor compounds for
the treatment of hepatitis C. This update will be presented on Tuesday,
January 8, at 2:30 p.m. PT at the JP Morgan Healthcare Conference in San
Francisco, CA.
Second-Generation Nucleoside Polymerase Inhibitor Program
Idenix's preclinical HCV nucleoside polymerase inhibitor program comprises
two novel nucleotide prodrugs, IDX184 and IDX102. This program is based on
Idenix's proprietary liver-targeting technology, which delivers high levels of
nucleoside triphosphate in the liver, potentially maximizing drug efficacy and
limiting systemic side effects.
In preclinical studies using an HCV replicon assay, IDX184 exhibited 10
times greater potency than nucleosides currently in clinical development. In a
7-day preclinical toxicology study of IDX184, no toxicities, including
gastrointestinal or hematological, were observed in monkeys at doses greater
than or equal to 600 mg/kg/day. In HCV genotype-1 infected chimpanzees, once-
daily oral administration of 10 mg/kg of either nucleotide prodrug produced a
rapid and potent inhibition of HCV replication with mean viral load reductions
ranging from 1.5 log(10) with IDX102 to 2.5-4.0 log(10) with IDX184 after 4
days of dosing. IDX184 has been selected as the company's lead candidate from
this program and clinical data are expected in 2008.
Novel Macrocyclic Protease Inhibitor Program
Idenix is evaluating multiple scaffolds in its protease inhibitor
discovery program. Compounds from two of these scaffolds have demonstrated
potent and selective antiviral activity in in vitro preclinical studies to
date. Several compounds have demonstrated subnanomolar potency against the HCV
NS3 protease target, single nanomolar potency in the HCV replicon, and no
inhibition of 8 human cellular proteases. Initial preclinical pharmacokinetic
evaluation of these compounds suggests the potential for once-daily or twice-
daily dosing. Clinical candidates from this program have been selected and
IND-enabling toxicology studies are ongoing.
"Our second-generation HCV drug candidates could offer improvements over
direct-acting compounds currently in clinical development," said Jean-Pierre
Sommadossi, Idenix's chairman and chief executive officer. "For example, in
preclinical studies our second-generation polymerase inhibitor, IDX184,
delivered multi-log viral load reductions in HCV genotype-1 infected
chimpanzees in just 4 days -- on par with the antiviral activity reported to
date from protease inhibitors currently in development."
Sommadossi continued, "In 2008, we look forward to advancing our
nucleotide prodrug and macrocyclic protease inhibitor programs into the clinic
to determine whether the promising preclinical data generated to date bears
out in HCV-infected patients. If successful, the combination of our second-
generation polymerase and protease inhibitors could lead to very exciting
changes in the HCV treatment paradigm."
2007 Financial Guidance
Idenix today reaffirmed prior 2007 financial guidance of ending 2007 with
between $100 million and $110 million of cash, cash equivalents and marketable
securities. The company's 2007 financial results have not yet been finalized
or audited.
About Idenix
Idenix Pharmaceuticals, Inc., headquartered in Cambridge, Massachusetts,
is a biopharmaceutical company engaged in the discovery and development of
drugs for the treatment of human viral and other infectious diseases. Idenix's
current focus is on the treatment of infections caused by hepatitis C virus
and HIV. For further information about Idenix, please refer to www.idenix.com.
Forward-looking Statements
This press release contains "forward-looking statements" within the
meaning of The Private Securities Litigation Reform Act of 1995. Such forward-
looking statements can be identified by the use of forward-looking terminology
such as "could," "may," "plans," "will," or similar expressions, or by express
or implied statements with respect to the company's clinical development
programs in hepatitis C, or any potential pipeline candidates for the
treatment of hepatitis C. Such forward-looking statements involve known and
unknown risks, uncertainties and other factors that may cause actual results
to be materially different from any future results, performance or
achievements expressed or implied by such statements. There can be no
guarantees that the company will advance any clinical product candidate or
other component of its potential pipeline to the clinic, to the regulatory
process or to commercialization. In particular, management's expectations
could be affected by unexpected regulatory actions or delays; uncertainties
relating to, or unsuccessful results of, pre-clinical studies and/or clinical
trials, including additional data relating to the ongoing pre-clinical studies
and/or clinical trials evaluating its product candidates; the company's
ability to obtain additional funding required to conduct its research,
development and commercialization activities; the company's dependence on its
collaboration with Novartis Pharma AG; changes in the company's business plan
or objectives; the ability of the company to attract and retain qualified
personnel; competition in general; and the company's ability to obtain,
maintain and enforce patent and other intellectual property protection for its
product candidates and its discoveries. These and other risks which may impact
management's expectations are described in greater detail under the caption
"Risk Factors" in the company's annual report on Form 10-K for the year ended
December 31, 2006 and the Quarterly Report on Form 10-Q for the quarter ended
September 30, 2007, each as filed with the Securities and Exchange Commission
(SEC) and other filings that the company makes with the SEC.
All forward-looking statements reflect the company's expectations only as
of the date of this release and should not be relied upon as reflecting the
company's views, expectations or beliefs at any date subsequent to the date of
this release. Idenix anticipates that subsequent events and developments may
cause these views, expectations and beliefs to change. However, while Idenix
may elect to update these forward-looking statements at some point in the
future, it specifically disclaims any obligation to do so.
Idenix Pharmaceuticals' Contact:
Teri Dahlman (617) 995-9905
SOURCE Idenix Pharmaceuticals, Inc.

Teri Dahlman of Idenix Pharmaceuticals, Inc., +1-617-995-9905