New Breast Cancer Treatment Launched in UK

HATFIELD, England, May 25, 2011 -

Halaven(TM) Black Triangle Drug (eribulin), a novel treatment for
patients with locally advanced or metastatic breast cancer who have
progressed after at least two chemotherapeutic regimens for advanced disease
is launched today in the United Kingdom. Prior therapy should have included
two common types of chemotherapy, an anthracycline and a taxane, unless
patients were not suitable for these treatments.[1]

Discovered and developed by Eisai, eribulin is a non-taxane,
microtubule dynamics inhibitor and a synthetic analog of halichondrin B, a
natural product isolated from the marine sponge Halichondria okadai.[2] It is
a new class of agent and the first, single-agent chemotherapy to demonstrate
a statistically significant overall survival benefit in patients with heavily
pre-treated advanced breast cancer compared to currently used treatments.
[1,3] Patients treated with eribulin survived a median of 2.5 months longer
than patients who received treatment of physician's choice (overall survival
of 13.1 months versus 10.6 months, respectively, p=0.041).[1,3]

Breast cancer is the most common cancer in the UK.[4] It accounts
for around 16 percent of female deaths from cancer, the second most common
cause of female cancer death after lung cancer.[5] 30 percent of women
diagnosed with early or localised breast cancer will eventually relapse and
develop metastatic or advanced disease.[6]

"Eribulin addresses an urgent need for new treatment options for
women with advanced breast cancer who have previously received multiple
treatments," says Dr Andrew Wardley, Consultant Medical Oncologist and
Co-Chair of the Breast Group at The Christie Hospital in Manchester.

Eribulin received European Commission approval on 17 March 2011
based on the results of the global Phase III EMBRACE study (Eisai Metastatic
Breast Cancer Study Assessing Treatment of Physician's Choice (TPC) Versus
Eribulin E7389).

The most commonly reported adverse reactions among patients
treated with eribulin were asthenia (fatigue), neutropenia, alopecia (hair
loss), peripheral neuropathy (numbness and tingling in arms and legs), nausea
and constipation.[3]

"As a charity that supports patients living with metastatic
(secondary) breast cancer, we have heard from many UK women that they feel
there are limited treatment options available to them. The UK launch of
eribulin is a step towards a drug being made available to these patients
which could help give them precious extra time," commented Maria Leadbeater,
clinical nurse specialist - metastatic (secondary) breast cancer, Breast
Cancer Care.

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 low molecular weight organic
compounds, therapeutic vaccines, monoclonal antibody-based therapies,
biologics, 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

Halaven is the EU trade name for eribulin.

Global Phase III Clinical Study (EMBRACE)
EMBRACE was an open-label, randomised, global, multi-centre, parallel two-arm
study designed to compare overall survival in patients treated with eribulin
versus a Treatment of Physician's Choice (TPC arm). TPC was defined as any
single-agent chemotherapy, hormonal treatment or biologic therapy approved
for the treatment of cancer; or palliative treatment or radiotherapy
administered according to local practice. The study included 762 patients
with metastatic breast cancer who previously had been treated with at least
two and a maximum of five prior chemotherapies, including an anthracycline
and a taxane. The vast majority (97%) of patients in the TPC arm received
chemotherapy.[3]

The most common adverse reactions (incidence greater than or equal to
19%) among patients treated with eribulin were asthenia (fatigue),
neutropenia, alopecia (hair loss), peripheral neuropathy (numbness and
tingling in arms and legs), nausea and constipation. The most common serious
side effect reported in patients receiving eribulin was neutropenia, with or
without fever (occuring in 45% and 5% of patients respectively).[3] The most
common adverse reaction resulting in discontinuation of treatment with
eribulin was peripheral neuropathy (five percent).[3]

Metastatic Breast Cancer

Breast cancer is now the most common cancer in the UK and the lifetime
risk of being diagnosed with breast cancer is 1 in 8 for women in the UK.[4]
In 2008, almost 47,700 women were diagnosed with breast cancer, around 130
women a day.[4]

Metastatic breast cancer is an advanced stage of the disease that
occurs when cancer spreads beyond the breast to other parts of the body.
Approximately five percent of women with breast cancer will have metastatic
disease at the time of diagnosis[7] and others with local and regional
disease may eventually develop metastatic disease.[6] An estimated 13 percent
of women presenting with metastatic breast cancer will survive beyond five
years.[7]

Halaven(TM) Black Triangle Drug (eribulin)

Eribulin is a non-taxane, microtubule dynamics inhibitor indicated for
the treatment of patients with breast cancer who have previously received at
least two chemotherapeutic regimens for metastatic disease and whose prior
therapy should have included an anthracycline and a taxane.[1] Eribulin
belongs to a class of antineoplastic agents, the halichondrins, which are
natural products, isolated from the marine sponge Halichondria okadai. It is
believed to work by inhibiting the growth phase of microtubule dynamics
without affecting the shortening phase and sequesters tubulin into
non-productive aggregates.

About Eisai

Eisai is one of the world's leading R&D-based pharmaceutical companies
that has defined its corporate mission as "giving first thought to patients
and their families and to increasing the benefits health care provides,"
which we call human health care (hhc).

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

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

- Integrative Oncology: Anticancer therapies; tumour regression, tumour
suppression, antibodies, etc and Supportive cancer therapies; pain relief,
nausea, etc

- Vascular/Immunological Reaction: Acute coronary syndrome,
atherothrombotic disease, sepsis, rheumatoid arthritis, psoriasis, Crohn's
disease, etc

With operations in the U.S., Asia, Europe and its domestic home market of
Japan, we employ more than 10,000 people worldwide, and reported consolidated
sales of over £3.53 billion in FY2007, an increase of 8.9% year on year. In
Europe, Eisai undertakes sales and marketing operations in over 20 markets,
including the United Kingdom, France, Germany, Italy, Spain, Switzerland,
Sweden, Ireland, Austria, Denmark, Finland, Norway, Portugal, Iceland, Czech
Republic, Hungary, Slovakia and the Netherlands.

For further information please visit our web site www.eisai.com

References

———————————

[1] Summary of Product Characteristics Halaven (updated March
2011). Available at:
www.medicines.org.uk/EMC/medicine/24382/SPC/Halaven+0.44+mg+ml+solution+for+injection/

[2] Jordan MA et al. The primary antimitotic mechanism of action
of the synthetic halichondrin E7389 is suppression of microtubule growth. Mol
Cancer Ther 2005;4:1086-95

[3] Cortes J, O'Shaughnessy J, Loesch D, et al. Eribulin monotherapy
versus treatment of physician's choice in patients with metastatic breast
cancer (EMBRACE): a phase 3 open-label randomised study. The Lancet.
2011; 377: 914 -923

[4] Cancer Research UK. Cancer Statistics - Key Facts. Available
from URL info.cancerresearchuk.org/cancerstats/types/breast/
(Accessed 1 April 2011)

[5] Cancer Research UK. Breast cancer mortality statistics 2004.
info.cancerresearchuk.org/cancerstats/types/breast/mortality/
(Accessed 1 April 2011)

[6] O'Shaughnessy. Extending Survival with Chemotherapy in Metastatic
Breast Cancer. The Oncologist. 2005;10;20-29

[7] Cancer Research UK. Statistics and outlook for breast cancer.
Available from URL
www.cancerhelp.org.uk/type/breast-cancer/treatment/statistics-and-outlook-for-breast-cancer
(Accessed 1 April 2011)

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Media Enquiries: Eisai Europe Ltd, Cressida Robson, +44-7908-314-155, Cressida_Robson at eisai.net . Tonic Life Communications, Benjamyn Tan / Juliet Morley, +44(0)207-798-9900 / +44(0)7747111217, benjamyn.tan at toniclc.com , eisaioncology at toniclc.com .