Astellas and Medivation Announce Initiation of Phase 2 Clinical Trial Comparing MDV3100 With Bicalutamide in Advanced Prostate Cancer

LONDON, STAINES, England and SAN FRANCISCO, March 30, 2011 - Astellas Pharma Europe Ltd. and Medivation, Inc. today announced
treatment of the first patient in the TERRAIN trial, a Phase 2 comparison of
the investigational drug MDV3100, a triple-acting, oral androgen receptor
antagonist, with bicalutamide, a commonly used non-steroidal anti-androgen,
for the treatment of advanced prostate cancer in patients who have progressed
while on LHRH analogue therapy or following surgical castration.

"Given the novel mechanism of MDV3100, this study has the potential to
answer fundamental clinical questions about continued androgen receptor
signalling in patients with progressive prostate cancer despite castrate
levels of testosterone," said Professor Axel Heidenreich, Principal
Investigator of the TERRAIN trial, from Universitätsklinikum der RWTH in
Aachen, Germany, "We look forward to the results of this important trial."

The TERRAIN Phase 2 trial is expected to enroll approximately 370
patients in Europe and North America. The primary endpoint of the trial is
progression-free survival.

"MDV3100 has been shown in preclinical studies to provide more complete
suppression of the androgen receptor signalling pathway than existing
anti-androgens and the TERRAIN study provides the opportunity to investigate
this finding further in a clinical setting," said Lynn Seely, M.D., Chief
Medical Officer of Medivation. "MDV3100 is currently in Phase 3 testing for
advanced prostate cancer, but our goal is to determine if MDV3100 can benefit
men with prostate cancer earlier in the course of the disease."

"This is the first of two Phase 2 trials in earlier-stage disease that we
and our partner Medivation will initiate this year to evaluate the potential
benefit of MDV3100 in a broad spectrum of prostate cancer patients," said
Steven Ryder, M.D., President, Astellas Pharma Global Development. "The
second of our new Phase 2 trials will study MDV3100 in an even earlier-stage
population - hormone naïve prostate cancer patients who are indicated for
androgen deprivation therapy. We expect to begin that trial in the first half
of this year."

MDV3100 Phase 3 Clinical Development Programme

In addition to the TERRAIN trial, MDV3100 is currently being evaluated in
two global Phase 3 studies in patients with advanced prostate cancer.

The randomised, double-blind, placebo-controlled Phase 3 AFFIRM trial
completed enrollment in November 2010. This trial of 1,199 patients with
advanced prostate cancer who were previously treated with docetaxel-based
chemotherapy is evaluating 160 mg/day of MDV3100 versus placebo. The primary
endpoint is overall survival.

A second Phase 3 clinical trial of MDV3100 in advanced prostate cancer,
the PREVAIL trial, is currently enrolling patients. This randomised,
double-blind, placebo-controlled, multi-national trial of approximately 1,700
men with advanced prostate cancer who have not yet received chemotherapy is
evaluating MDV3100 at a dose of 160 mg taken orally once daily plus standard
of care versus placebo plus standard of care. The co-primary endpoints of the
trial are overall survival and progression-free survival.

About the Medivation/Astellas Collaboration

In October 2009, Medivation and Astellas entered into a global agreement
to jointly develop and commercialise MDV3100. The companies are collaborating
on a comprehensive development programme that includes studies to develop
MDV3100 across the full spectrum of advanced prostate cancer disease states.
Subject to receipt of regulatory approval, the companies will jointly
commercialise MDV3100 in the U.S. and Astellas will have responsibility for
commercialising MDV3100 outside the U.S.. Medivation received a $110 million
up-front payment upon entering into the collaboration agreement, and is
eligible to receive up to $335 million in development milestone payments, up
to $320 million in commercial milestone payments, 50% of profits on sales in
the U.S., and tiered, double-digit royalties on sales outside the United
States.

About MDV3100

MDV3100 is an investigational therapy in clinical development for
advanced prostate cancer. In a Phase 1-2 trial in 140 patients with advanced
prostate cancer published in The Lancet in April 2010, encouraging
anti-tumour activity was noted with MDV3100 across endpoints. In preclinical
experiments published in Science in April 2009, the triple-acting, oral
androgen receptor antagonist provided more complete suppression of the
androgen receptor pathway than bicalutamide, the most commonly used
anti-androgen. MDV3100 slows growth and induces cell death in
bicalutamide-resistant cancers via three complementary actions - MDV3100
blocks testosterone binding to the androgen receptor, impedes movement of the
androgen receptor to the nucleus of prostate cancer cells (nuclear
translocation) and inhibits binding to DNA. In the preclinical experiments
published in Science, MDV3100 was superior to bicalutamide in each of these
three actions.

About Prostate Cancer

Prostate cancer is the second most common non-skin cancer among men in
the world, and it is the sixth leading cause of cancer death among men
worldwide. Patients whose prostate tumours have stopped responding to, or are
growing despite the use of active hormone treatment strategies are considered
to have advanced prostate cancer. These patients have a poor prognosis and
few treatment options.

This press release contains forward-looking statements, including
statements regarding the continued clinical development of Medivation's
product candidates, the therapeutic and commercial potential of MDV3100, the
planned initiation of additional clinical trials and the continued
effectiveness of, and continuing collaborative activities under, Medivation's
collaboration agreements with Pfizer and Astellas, which are made pursuant to
the safe harbor provisions of the Private Securities Litigation Reform Act of
1995. Any statements contained in this press release that are not statements
of historical fact may be deemed to be forward-looking statements.
Forward-looking statements involve risks and uncertainties that could cause
Medivation's actual results to differ significantly from those projected,
including, without limitation, risks related to progress, timing and results
of Medivation's clinical trials, including the risk that adverse clinical
trial results could alone or together with other factors result in the delay
or discontinuation of some or all of Medivation's product development
activities, enrollment of patients in Medivation's clinical trials,
partnering of Medivation's product candidates, including Medivation's
dependence on the efforts of and funding by Astellas for the development of
MDV3100, the achievement of development, regulatory and commercial milestones
under Medivation's collaboration agreements, the manufacturing of
Medivation's product candidates, the adequacy of Medivation's financial
resources, unanticipated expenditures or liabilities, intellectual property
matters, and other risks detailed in Medivation's filings with the Securities
and Exchange Commission, including its annual report on Form 10-K for the
year ended December 31, 2010, filed on March 16, 2011 with the SEC. You are
cautioned not to place undue reliance on the forward-looking statements,
which speak only as of the date of this release. Medivation disclaims any
obligation or undertaking to update or revise any forward-looking statements
contained in this press release.

About Astellas Pharma Europe Ltd.

Astellas Pharma Europe Ltd., located in the UK, is a European subsidiary
of Tokyo-based Astellas Pharma Inc. Astellas is a pharmaceutical company
dedicated to improving the health of people around the world through the
provision of innovative and reliable pharmaceuticals. The organisation is
committed to becoming a global company by combining outstanding R&D and
marketing capabilities and continuing to grow in the world pharmaceutical
market. Astellas Pharma Europe Ltd. is responsible for 21 affiliate offices
located across Europe, the Middle East and Africa, an R&D site and three
manufacturing plants. The company employs approximately 3,900 staff across
these regions. For more information about Astellas Pharma Europe, please
visit www.astellas.eu.

About Medivation, Inc.

Medivation, Inc. is a biopharmaceutical company focused on the rapid
development of novel small molecule drugs to treat serious diseases for which
there are limited treatment options. Medivation aims to transform the
treatment of these diseases and offer hope to critically ill patients and
their caregivers. Together with its corporate partners Astellas and Pfizer,
Medivation currently has investigational drugs in Phase 3 development to
treat advanced prostate cancer, mild-to-moderate Alzheimer's disease and
Huntington disease. For more information, please visit us at
www.medivation.com.

www.astellas.eu

www.medivation.com

Contacts for inquiries or additional information: Astellas Pharma Europe Ltd., Corporate Communications, Mindy Dooa, Tel: +44(0)1784-419408; Medivation, Inc., Chief Business Officer, Patrick Machado, Tel: +1-415-829-4101