Eisai's Eribulin (Halaven(R)) Receives Swissmedic Approval for use in Locally Advanced and Metastatic Breast Cancer

Swissmedic Approval Paves the Way for Forthcoming Eribulin Availability in Switzerland

HATFIELD, England, May 17, 2011 - Eribulin (Halaven(R)) is today approved for use in Switzerland by
Swissmedic, the Swiss Agency for Therapeutic Products, as a monotherapy
treatment of patients with locally advanced and metastatic breast carcinoma
with progression after prior therapy with an anthracycline, a taxane and
capecitabine.[1] Breast cancer is the second most commonly diagnosed cancer
worldwide and there are about 1.3 million new cases of the disease
annually.[2] More than 5,000 Swiss women have the disease and approximately
1,400 are likely to die annually.[3]

Eisai submitted a New Drug Application based on the results from a Phase
II study (Study 211) of eribulin in order to deliver the medicine to patients
as quickly as possible. The approval was based upon the Phase II and Phase
III data.[4]

Dr Matti Aapro, Dean of the Multidisciplinary Oncology Institute,
Genolier, Switzerland commented, "This is a significant medical advance in a
setting where there is currently no recognised standard of care. Until now we
have not had robust clinical trial data to guide our treatment of these
patients so I welcome today's news of the Swissmedic approval for use of
eribulin which will allow patients in Switzerland to gain access to this
important new treatment. The EMBRACE study demonstrates that eribulin is an
effective and relatively well-tolerated treatment, as well as the first
single agent chemotherapy to provide statistically significant overall
survival improvements for patients with metastatic breast cancer previously
treated with an anthracycline and a taxane.*"

The Swissmedic approval means that patients in Switzerland will soon be
able to benefit from this innovative treatment. Eribulin is approved for
treatment for women with locally advanced or metastatic breast cancer who
have progressed after previous treatment with an anthracycline, a taxane and
capecitabine.

Eribulin is the first single-agent chemotherapy to demonstrate a
significant overall survival benefit in patients with advanced breast cancer
in the population studied within EMBRACE. The Swissmedic approval means that
patients in Switzerland will soon be able to benefit from this innovative
treatment.

Eribulin was approved in the USA in November 2010, in Singapore in
February 2011, in Europe in March 2011 and Japan in April 2011, and has
already been launched in USA, UK, Nordics and Japan.

Eisai's commitment to meaningful progress in oncology research, built on
scientific expertise, is supported by a global capability to conduct
discovery and preclinical research, and develop small molecules, biologic and
supportive care agents for cancer across multiple indications. Through these
efforts, Eisai will make further contributions to addressing the
diversified needs of and increasing the benefits provided to patients and
their families as well as healthcare professionals as it seeks to fulfill its
human health care (hhc) mission.

NOTES TO EDITORS

About Eribulin

Eribulin is a non-taxane, microtubule dynamics inhibitor, fully synthetic
analogue, belonging to a class of antineoplastic agents, the halichondrins,
which are natural products isolated from the marine sponge Halichondria
okadai[5],[6]. Eribulin targets microtubules, the major cytoskeletal
component of cells which play a pivotal role in cell replication. Alteration
of microtubule dynamics can cause a cell to stop dividing and self destruct.

About the 211 Study

Study 211 is a Phase II, open-label, single-arm study evaluating the
efficacy and safety of eribulin in patients with locally advanced or
metastatic breast cancer who had received an anthracycline, a taxane and
capecitabine as prior therapy, and who were refractory to their last
chemotherapy regimen, as documented by progression on or within six months of
that therapy. Of 299 patients enrolled in the study, 291 were treated with
eribulin. Two-hundred sixty-nine patients met the key inclusion criteria.
Independent assessment of objective response rate (ORR) was 9.3%. Nearly half
(46.5%) the patients had stable disease after treatment with eribulin. The
median duration of response was 4.1 months. Median progression-free survival
was 2.6 months, and the median overall survival rate was 10.4 months. The
six-month PFS and OS rates were 15.6% and 72.3%, respectively.[7]

The safety analysis included all 291 patients who received treatment with
eribulin. The most frequently reported Grade 3 or Grade 4 adverse events were
neutropenia 54%, febrile neutropenia 5.5%, leucopenia 14%, and
weakness/fatigue (10%; no Grade 4 events). Grade 3 peripheral neuropathy was
reported in 6.9% of patients. No Grade 4 peripheral neuropathy events were
reported.[7]

About EMBRACE

EMBRACE was an open-label, randomised, multi-centre study of 762 women
with MBC who were previously treated with at least two and a maximum of five
prior chemotherapies (greater than or equal to 2 for advanced disease),
including an anthracycline and a taxane. Patients must have been refractory
to the most recent chemotherapy, documented by progression on or within six
months of therapy. The study was designed to compare OS in patients treated
with eribulin versus a TPC arm, reflecting a real-world clinical setting
where a variety of agents are used to treat patients. The primary endpoint
was OS. Secondary endpoints were objective response rate, progression-free
survival, safety and duration of response.[4]

About Metastatic Breast Cancer

Worldwide, more than one million women a year are diagnosed with breast
cancer, including 421,000 women in Europe.[8,9] Approximately 30 percent of
women initially diagnosed with earlier stages of breast cancer eventually
develop recurrent or metastatic disease,[10] and while around 9 out of 10 of
women diagnosed with early stage breast cancer survive beyond five years,
this drops to around 1 in 10 among women first diagnosed with MBC.[11] Most
MBC patients have a limited survival time of approximately 18-24 months.[12]

Eisai in Oncology

Eisai is dedicated to discovering, developing and producing innovative
oncology therapies that can make a difference and impact the lives of
patients and their families. This passion for people is part of Eisai's human
health care (hhc) mission, which strives for better understanding of the
needs of patients and their families to increase the benefits health care
provides. Our commitment to meaningful progress in oncology research, built
on scientific expertise, is supported by a global capability to conduct
discovery and preclinical research, and develop small molecules, therapeutic
vaccines, biologic and supportive care agents for cancer across multiple
indications.

Eisai Europe Limited

Eisai concentrates its R&D activities in three key areas:

- Integrative Neuroscience, including: Alzheimer's disease, multiple
sclerosis, neuropathic pain, epilepsy, depression

- Integrative Oncology, including: anticancer therapies; vaccines, tumor
regression, tumor suppression, antibodies and supportive cancer therapies;
pain relief, nausea

- Vascular/Immunological reaction, including: acute coronary syndrome,
atherothrombotic disease, severe sepsis, rheumatoid arthritis, psoriasis,
Crohn's disease

- In Europe, Eisai undertakes sales and marketing operations in over 20
markets.

Eisai

Eisai is a research-based human health care (hhc) company that discovers,
develops and markets products throughout the world. Through a global network
of research facilities, manufacturing sites and marketing subsidiaries, Eisai
actively participates in all aspects of the worldwide health care system.
Eisai employs approximately 11,000 employees worldwide.

For further information, please visit www.eisai.co.jp.

* Eribulin-mesylate is indicated for the treatment of patients with
locally advanced or metastatic breast cancer that has progressed after prior
anthracycline, taxane, and capecitabine therapy.

———————————

[1] Swiss medic approval letter

[2] Sources: GLOBOCAN 2008, Cancer Incidence and Mortality Worldwide:
IARC CancerBase No. 10 [Internet]

[3] globocan.iarc.fr/factsheets/populations/factsheet.asp?uno=756

[4] Cortes J, O'Shaughnessy J, Loesch D, et al. A Phase III open-label
randomized study (EMBRACE) or eribulin monotherapy versus treatment of
physician's choice in patients with metastatic breast cancer. The Lancet.
2011; 377: 914 -923

[5] Kuznetsov G, Towle MJ, Cheng H, et al: Induction of morphological and
biochemical apoptosis following prolonged mitotic blockage by halichondrin B
macrocyclic ketone analog E7389. Cancer Res 2004; 64: 5760-5766

[6] Towle MJ, et al. In Vitro and In Vivo Anticancer Activities of
Synthetic Macrocyclic Ketone Analogues of Halichondrin B. Cancer Res 2001;
61: 1013-1021

[7] Cortes et al. Phase II Study of the Halichondrin B Analog Eribulin
Mesylate in Patients With Locally Advanced or Metastatic Breast Cancer
Previously Treated With an Anthracycline, a Taxane, and Capecitabine. Jour
Clin Oncol, September 1, 2010 vol. 28 no. 25 3922-3928.

[8] Coughlin, S. Breast cancer as a global health concern. Cancer
Epidemiology, October 2009; 33: 315-18.

[9] Ferlay J, Parkin DM, Steliarova-Foucher E. Estimates of cancer
incidence and mortality in Europe in 2008. Eur J Cancer.2010: 46(4):765-781

[10] O'Shaughnessy J. Extending survival with chemotherapy in metastatic
breast cancer. Oncologist. 2005;10 Suppl 3:20-29

[11] Cancer Research UK, Breast Cancer Statistics - Key Facts [updated
April 2010]. Available from:
info.cancerresearchuk.org/cancerstats/types/breast/index.htm?script=true
(accessed (04/08/10)

[12] Fernandez Y, Cueva J, Palomo AG, et al. Novel therapeutic approaches
to the treatment of metastatic breast cancer. Cancer Treat
Rev.2010:36(1):33-42

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Media Enquiries: Eisai Europe Ltd, Cressida Robson, +44-7908-314-155, Cressida_Robson at eisai.net