Anadys to Halt Development of Investigational Hepatitis C Drug
ANA975
Anadys
Pharmaceuticals announced last week that it will discontinue development of its
investigational anti-HCV drug candidate, ANA975, a toll-like receptor 7 agonist.
Anadys was developing the agent in collaboration with Novartis.
The
decision comes in the wake of disappointing data from toxicology studies in animals.
Toll-like receptor agents can cause excessive immune stimulation, leading to a
range of side effects.
Below
is an excerpt from the Anadys press release announcing the decision:
Development
Discontinued for ANA975, an Early Stage Compound for Treatment of Hepatitis C
Virus Infection
SAN DIEGO,
July 26, 2007 -- PRNewswire-FirstCall via COMTEX News Network -- Anadys Pharmaceuticals,
Inc. (Nasdaq: ANDS) today announced that it and Novartis have decided to discontinue
the development of ANA975, a phase 1b compound for the treatment of hepatitis
C virus (HCV) infection. The parties have determined that the results received
to date from the ongoing 13 week toxicology study together with the results observed
in the previous 13 week toxicology study do not support further clinical evaluation
of chronic daily dosing of ANA975 in hepatitis C patients.
"Although
we are disappointed to discontinue development of ANA975, our animal toxicology
results have convinced us that chronic daily dosing of this compound is inappropriate
for further clinical development," said Lawrence C. Fritz, Ph.D., president
and chief executive officer of Anadys. "However, we remain optimistic that
TLR7 agonists offer therapeutic potential as effective immunomodulators in multiple
disease areas, albeit using alternative dosing schedules, and our plans to develop
ANA773 for cancer treatment continue unabated," Dr. Fritz said.
Anadys
continues its development of ANA773, another TLR7 agonist prodrug distinct from
ANA975, and expects to file an IND by the end of 2007. Anadys plans to evaluate
ANA773 in Phase 1 clinical trials for the treatment of advanced cancer. This program
is independent of the Novartis collaboration and is not affected by the decision
to discontinue development of ANA975.
First and
Second Toxicology Study Results
In June 2006, Anadys and Novartis
suspended dosing in their 28-day phase 1b clinical trial of ANA975 in HCV infected
patients due to then recently obtained information from pre-clinical 13-week toxicology
studies. No clinical observations contributed to this decision. Preliminary analysis
of the toxicology information revealed various new observations which appeared
consistent with intense immune stimulation in animals. Subsequently, the FDA put
the ANA975 IND on full clinical hold. In November 2006, Anadys and Novartis initiated
a second 13-week toxicology study to understand better the observations from the
first toxicology study and to assist in determining a future course of action
for the program.
Analysis of available data from the second 13-week toxicology
study, together with the results from the initial 13-week toxicology study led
the parties to determine that: 1) chronic daily dosing of ANA975 was unlikely
to provide an adequate therapeutic index; and 2) additional preclinical evaluation
would be necessary to determine if alternate dosing schedules of ANA975 would
support a safety margin sufficient for further development of this compound for
the treatment of patients chronically infected with hepatitis C.
About
TLR-7
Toll-like receptor 7 (TLR7) is a pattern-recognition
receptor that activates the innate immune response. Stimulation of TLR7 induces
the release of interferon-alpha and other type I interferons from immune cells,
the release of various pro-inflammatory cytokines, the upregulation of co-stimulatory
molecules and the development of an adaptive immune response. Small-molecule TLR7
agonists have been shown to have broad antiviral and anticancer effects in preclinical
models and in some clinical settings.
About Anadys
Anadys Pharmaceuticals, Inc., http://www.anadyspharma.com,
is a biopharmaceutical company committed to advancing patient care by discovering,
developing and commercializing novel small molecule medicines for the treatment
of viral diseases and cancer. The Company's programs focus on Toll-Like Receptor-based
small molecule product candidates and direct antiviral compounds that inhibit
key steps in viral proliferation. The Company has core expertise in medicinal
chemistry coupled with cell biology and structure-based drug design, and is developing
compounds for the treatment of hepatitis C infection, hepatitis B infection and
cancer.
08/03/07
Reference Anadys
Pharmaceuticals. Development Discontinued for ANA975, an Early Stage Compound
for Treatment of Hepatitis C Virus Infection. Press release. July 26, 3007.
