Enanta Pharmaceuticals Presents New Preclinical Data on Compounds Targeting Hepatitis B Virus and Non-Alcoholic Steatohepatitis at The International Liver Congress™ 2019

WATERTOWN, Mass.–(BUSINESS WIRE)–Enanta Pharmaceuticals, Inc. (NASDAQ:ENTA), a research and
development-focused biotechnology company dedicated to creating small
molecule drugs for viral infections and liver diseases, announced that
new preclinical data from Enanta’s wholly-owned development programs for
hepatitis B virus (HBV) and non-alcoholic steatohepatitis (NASH) will be
presented at The International Liver Congress™ (ILC) 2019, in Vienna,
Austria.

New data include a presentation on development candidate EDP-514,
Enanta’s core inhibitor for HBV that is expected to enter into a Phase 1
clinical study in the second half of 2019. Presentations also focus on
Enanta’s NASH program, featuring new data on the FXR agonist EDP-305,
and including in vivo data on EP-027315 and EP-026856, two
prototype compounds from Enanta’s ASK-1 (apoptosis signal-regulating
kinase 1) inhibitor project.

“Enanta continues to generate an abundance of preclinical and clinical
data on our development candidates EDP-514 for HBV, and EDP-305 for
NASH,” stated Jay R. Luly, President and CEO, Enanta. “Our extensive
scientific research provides us the knowledge and confidence to move
forward our best candidates with the highest likelihood of success. We
look forward to announcing clinical results of EDP-305 in our ARGON-1
Phase 2 study in NASH patients in the third quarter and to initiating a
phase 1 study with EDP-514 during the second half of 2019.”

A summary of the poster presentations at The International Liver
Congress™ (ILC) 2019 are below.

Full abstracts can be found at http://ilc-congress.eu.

April 11, 2019 – 09:00 – 19:00
THU-084: “A comparative
study of anti-Fibrotic therapeutics using aptamer-based quantitative
proteomics in a rat model of non-alcoholic steatohepatitis cirrhosis,” Smitha
Krishnan, United States

Data in this poster demonstrate that in a preclinical rat model of NASH
cirrhosis utilizing an aptamer-based proteomics assay, it was possible
to identify non-invasive biomarkers of treatment response and potential
pathways activated by different mechanisms currently under study in
clinical trials by Enanta and others. Three anti-fibrotic compounds were
evaluated: two ASK-1 inhibitors, Enanta compound EP-026856 and Gilead’s
selonsertib, and one FXR agonist, Enanta compound EDP-305. While all
three drugs were effective in inhibiting fibrosis development in this
12-week treatment model, EP-026856 showed the greatest effect on
returning non-invasive serum markers back to baseline.

April 12, 2019 – 09:00 – 17:00

FRI-191: “EDP-514, a novel HBV core inhibitor with potent
antiviral activity both in vitro and in
vivo,” Kai Lin, United States

Data in this poster demonstrate that EDP-514, a novel class II HBV core
inhibitor, is a potent inhibitor of HBV replication, and prevents the de
novo formation of new cccDNA in primary human hepatocytes when given
early during infection. Data also show that EDP-514 is pan-genotypic,
and that combinations of EDP-514 with nucleoside reverse-transcriptase
inhibitors (NRTIs, current anti-viral therapies for HBV) or a class I
core inhibitor result in additive to synergistic antiviral effects in
vitro. ln vivo, EDP-514 demonstrates excellent in vivo
efficacy with >4-log viral load reduction in HBV-infected PXB mice.

FRI-340: “In vivo effects of a novel inhibitor of apoptosis
signal-regulating kinase 1 in mouse models of liver injury and metabolic
disease,” Manuel Roqueta-Rivera, United States

Data in this poster demonstrate that EP-027315 is a potent and highly
selective inhibitor of ASK-1. It inhibits hepatic ASK-1 and decreases
liver pJNK (one of the stress-activated protein kinase signaling
pathways influencing inflammation in liver cells), plasma ALT (a common
marker of potential liver damage), and apoptosis (cell death) in a
dose-dependent manner in a mouse acute injury model. EP-027315 also
protects against liver injury in a diet-induced obesity model.
Suppression of markers of liver injury, inflammation, and apoptotic
pathways are observed at both a transcriptional and protein level.

About Enanta
Enanta Pharmaceuticals is using its robust,
chemistry-driven approach and drug discovery capabilities to become a
leader in the discovery and development of small molecule drugs for the
treatment of viral infections and liver diseases. Enanta’s research and
development efforts are currently focused on the following disease
targets: respiratory syncytial virus (RSV), non-alcoholic
steatohepatitis (NASH)/ primary biliary cholangitis (PBC), and hepatitis
B virus (HBV).

Enanta’s research and development activities are funded by royalties
from HCV products developed under its collaboration with AbbVie.
Glecaprevir, a protease inhibitor discovered by Enanta, is now sold by
AbbVie in numerous countries as part of its newest treatment for chronic
hepatitis C virus (HCV) infection. This leading HCV regimen is sold
under the tradenames MAVYRET™ (U.S.) and MAVIRET™ (ex-U.S.)
(glecaprevir/pibrentasvir). Please visit www.enanta.com
for more information.

Forward Looking Statements Disclaimer
This press release
contains forward-looking statements, including statements with respect
to the prospects for further developments with respect to EDP-305 for
NASH/PBC and EDP-514 for HBV. Statements that are not historical facts
are based on management’s current expectations, estimates, forecasts and
projections about Enanta’s business and the industry in which it
operates and management’s beliefs and assumptions. The statements
contained in this release are not guarantees of future performance and
involve certain risks, uncertainties and assumptions, which are
difficult to predict. Therefore, actual outcomes and results may differ
materially from what is expressed in such forward-looking statements.
Important factors and risks that may affect actual results include: the
development risks of early stage discovery efforts in the disease areas
in Enanta’s research and development pipeline, such as NASH, PBC and
HBV; the impact of development, regulatory and marketing efforts of
others with respect to competitive treatments for NASH, PBC and HBV;
Enanta’s limited clinical development experience; Enanta’s need to
attract and retain senior management and key scientific personnel;
Enanta’s need to obtain and maintain patent protection for its product
candidates and avoid potential infringement of the intellectual property
rights of others; and other risk factors described or referred to in
“Risk Factors” in Enanta’s most recent Form 10-Q for the quarter ended
December 31, 2018 and other periodic reports filed more recently with
the Securities and Exchange Commission. Enanta cautions investors not to
place undue reliance on the forward-looking statements contained in this
release. These statements speak only as of the date of this release, and
Enanta undertakes no obligation to update or revise these statements,
except as may be required by law.

Contacts

Investor Contact
Carol Miceli
617-607-0710
[email protected]

Media
Contact:
Kari Watson
MacDougall Biomedical Communications
781-235-3060
[email protected]