Positive Phase 2 Clinical Data With Tivantinib in Hepatocellular Carcinoma to be Highlighted in Oral Presentation at 2012 Annual Meeting of American Society of Clinical Oncology

Woburn, Massachusetts And Tokyo (ots/PRNewswire) -

ArQule, Inc. and Daiichi Sankyo, Co., Ltd. (TSE 4568) today
announced that an oral presentation at the Annual Meeting of the
American Society of Clinical Oncology (ASCO) will feature Phase 2
trial data with tivantinib as a single agent investigational
second-line treatment in hepatocellular carcinoma (HCC). ArQule
announced that this randomized, double-blind study met its primary
endpoint in January and will now present the full results from this
trial, including positive data in the pre-defined c-MET high
population. Additional clinical data with tivantinib will be featured
in two poster discussions and two general poster sessions. Abstracts
of these presentations with tivantinib have been published on
http://www.asco.org.

"These findings represent the first randomized data reported with
an investigational c-MET inhibitor administered as a single agent
second-line treatment in HCC," said Paolo Pucci, chief executive
officer of ArQule. "They clearly define c-MET high patients as a
biological subgroup for potential targeted therapy with tivantinib.
The robust statistical significance achieved in this trial reflects
the anti-cancer activity of tivantinib alone and expands its
therapeutic potential."

HCC Trial Summary: c-MET high patients

Data from the HCC trial demonstrated a statistically significant
improvement in time-to-progression (HR=0.43, log rank p-value=0.03),
accompanied by significant improvements in progression-free survival
and disease control rate among second-line patients with c-MET high
tumors who were treated with tivantinib. In addition, overall
survival data were observed favoring tivantinib-treated patients in
this population. Efficacy was similar in the two tivantinib dosing
subgroups (360 milligrams twice daily and 240 milligrams twice
daily), with less frequent neutropenia in the lower dose.

Previously announced top-line data from the HCC trial demonstrate
that treatment with tivantinib produced a statistically significant
56 percent improvement in TTP in the intent-to-treat (ITT) population
by central radiology review, the primary endpoint (HR = 0.64, log
rank p-value = 0.04) in this trial. Adverse events were reported at
similar rates in the treatment and placebo arms, except for a higher
incidence of fatigue and hematologic events, including neutropenia
and anemia, in tivantinib-treated patients. The incidence of
hematologic events declined following dose reduction of tivantinib
from 360 milligrams twice daily to 240 milligrams twice daily.

The schedule of this and other presentations of data with
tivantinib is provided below. All times are Central Daylight Time.

Oral Presentation
Date and time: Saturday, June 2, 2012, 5:00 PM - 5:15 PM
Abstract number: 4005
Poster title: Tivantinib (ARQ 197) versus placebo in patients (Pts) with hepatocellular
carcinoma (HCC) who failed one systemic therapy: Results of a randomized controlled
phase II trial (RCT)
Presenter: Lorenza Rimassa, MD
Location: E Hall D1
Poster Discussion Sessions
Date and time: Saturday, June 2, 2012, 8:00 AM - 12:00 PM
Abstract number: 4545
Poster title: Safety and efficacy of MET inhibitor tivantinib (ARQ 197) combined with
sorafenib in patients (pts) with renal cell carcinoma (RCC) from a phase 1 study
Poster board # 24
Presenter: Igor Puzanov, MD
Location: E450a
Date and time: Saturday, June 2, 2012, 1:15 PM - 5:15 PM
Abstract number: 8519
Poster title: Safety and efficacy of MET inhibitor tivantinib (ARQ 197) combined with
sorafenib in patients (pts) with NRAS wild-type or mutant melanoma from a phase 1
study
Poster board # 8
Presenter: Julie A. Means-Powell, MD
Location: E450b
General Poster Session
Date and time: Monday, June 4, 2012, 8:00 AM - 12:00 PM
Abstract number: 4117
Poster title: Safety and efficacy of MET inhibitor tivantinib (ARQ 197) combined with
sorafenib in patients (pts) with hepatocellular carcinoma (HCC) from a phase 1 study
Poster board # 50D
Presenter: Robert E. Martell, MD, PhD
Location: S Hall A2
Date and time: Monday, June 4, 2012, 8:00 AM - 12:00 PM
Abstract number: 4082
Poster title: A phase II study of tivantinib monotherapy in patients with previously
treated advanced or recurrent gastric cancer
Poster board # 46A
Presenter: Kei Muro, MD
Location: S Hall A2

Tivantinib is currently in Phase 3 development and has not yet
been approved for any indication.

About ArQule

ArQule is a biotechnology company engaged in the research and
development of next-generation, small-molecule cancer therapeutics.
The Company's targeted, broad-spectrum products and research programs
are focused on key biological processes that are central to human
cancers. ArQule's lead product candidate, in Phase 2 and Phase 3
clinical development together with development and commercialization
partner, Daiichi Sankyo, Co. Ltd, is tivantinib, an oral, selective
inhibitor of the c-MET receptor tyrosine kinase. The Company's
pipeline consists of ARQ 621, designed to inhibit the Eg5 kinesin
motor protein, and ARQ 736, designed to inhibit the RAF kinases.
ArQule's current discovery efforts, which are based on the ArQule
Kinase Inhibitor Platform (AKIP(TM)), are focused on the
identification of novel kinase inhibitors that are potent, selective
and do not compete with ATP (adenosine triphosphate) for binding to
the kinase.

http://www.ArQule.com

About Daiichi Sankyo

The Daiichi Sankyo Group is dedicated to the creation and supply
of innovative pharmaceutical products to address the diversified,
unmet medical needs of patients in both mature and emerging markets.
While maintaining its portfolio of marketed pharmaceuticals for
hypertension, hyperlipidemia, and bacterial infections, the Group is
engaged in the development of treatments for thrombotic disorders and
focused on the discovery of novel oncology and
cardiovascular-metabolic therapies. Furthermore, the Daiichi Sankyo
Group has created a "Hybrid Business Model," which will respond to
market and customer diversity and optimize growth opportunities
across the value chain. For more information, please visit
http://www.daiichisankyo.com.

This press release contains statements regarding the clinical
trials with tivantinib (ARQ 197) by ArQule and its business partner,
Daiichi Sankyo. These statements are based on the current beliefs and
expectations of both companies, and are subject to risks and
uncertainties that could cause actual results to differ materially.
Positive information about pre-clinical and early stage clinical
trial results does not ensure that later stage or larger scale
clinical trials will be successful. For example, tivantinib may not
demonstrate a promising therapeutic effect; in addition, it may not
demonstrate an appropriate safety profile in current or later stage
or larger scale clinical trials as a result of known or as yet
unanticipated side effects. The results achieved in later stage
trials may not be sufficient to meet applicable regulatory standards
or to justify further development. Problems or delays may arise
during clinical trials or in the course of developing, testing or
manufacturing these compounds that could lead ArQule or its partners
to discontinue development. Even if later stage clinical trials are
successful, unexpected concerns may arise from analysis of data or
from additional data. Obstacles may arise or issues may be identified
in connection with review of clinical data with regulatory
authorities. Regulatory authorities may disagree with ArQule's view
of the data or require additional data or information or additional
studies. In addition, the planned timing of initiation and completion
of clinical trials for tivantinib are subject to the ability of
ArQule, Daiichi Sankyo, and Kyowa Hakko Kirin, a licensee of
tivantinib, to enroll patients, enter into agreements with clinical
trial sites and investigators, and overcome technical hurdles and
other issues related to the conduct of the trials for which each of
them is responsible. There is a risk that these issues may not be
successfully resolved. Drug development involves a high degree of
risk. Only a small number of research and development programs result
in the commercialization of a product. Positive pre-clinical data may
not be supported in later stages of development. Furthermore, ArQule
may not have the financial or human resources to successfully pursue
drug discovery in the future. Moreover, with respect to partnered
programs, even if certain compounds show initial promise, Daiichi
Sankyo or Kyowa Hakko Kirin may decide not to license or continue to
develop them, as the case may be. In addition, Daiichi Sankyo and
Kyowa Hakko Kirin have certain rights to unilaterally terminate their
agreements with ArQule. If either company were to do so, ArQule might
not be able to complete development and commercialization of the
applicable licensed products on its own. For more detailed
information on the risks and uncertainties associated with the
ArQule's drug development and other activities, see the ArQule's
periodic reports filed with the Securities and Exchange Commission.
Neither ArQule, nor Daiichi Sankyo undertake any obligation to
publicly update any forward-looking statements.

ots Originaltext: ArQule, Inc. and Daiichi Sankyo, Co., Ltd.
Im Internet recherchierbar: http://www.presseportal.de

Contact:
Contact: William B. Boni, VP, Investor Relations/Corp.
Communications, +1(781)994-0300; Dr. Michaela Paudler-Debus, Daiichi
Sankyo, Co., Ltd., +81-3-6225-1338 (office)