Medivation and Astellas Announce Publication in The Lancet of Positive Efficacy Data From Phase 1-2 Trial of MDV3100 in Advanced Prostate Cancer Patients

Novel, Triple-Acting Oral Androgen Receptor Antagonist Currently in Phase 3 Development for Advanced Prostate Cancer

SAN FRANCISCO and TOKYO, April 15, 2010 - Medivation, Inc. (NASDAQ: MDVN) and Astellas Pharma Inc. today announced
publication of positive results from their previously reported Phase 1-2
trial of the novel triple-acting oral androgen receptor antagonist MDV3100 in
men with progressive, metastatic castration-resistant prostate cancer in the
April 15 online version of The Lancet. According to the published results,
MDV3100 demonstrated anti-tumor activity in patients with late-stage prostate
cancer as evaluated by reductions in prostate specific antigen (PSA) levels,
radiographic findings and circulating tumor cell (CTC) counts. Anti-tumor
effects were observed in patients who were resistant to standard
anti-androgen treatments, as well as in patients who had progressed following
chemotherapy. MDV3100 is currently in Phase 3 development for the treatment
of advanced prostate cancer.

"MDV3100, with its unique mechanism of action, could offer an important
new treatment option to men with prostate cancer that is resistant to
currently available anti-androgens," said Howard Scher, M.D., lead author of
The Lancet article and chief of the Genitourinary Oncology Service at
Memorial Sloan-Kettering Cancer Center in New York. "It is particularly
encouraging that antitumor activity was seen on all outcomes assessed in
patients who had failed chemotherapy because their survival times are one
year or less, on average, and their treatment options are limited."

Phase 1-2 Trial Design and Results

All patients in the open-label, dose-escalation, U.S. Phase 1-2 clinical
trial had progressive disease upon enrollment and were heavily pretreated,
with 77 percent having failed at least two lines of prior hormonal therapy
and 54 percent having failed one or more chemotherapy regimens. A total of
140 men were enrolled in the trial, which evaluated MDV3100 doses between 30
and 600 mg/day. Patients could remain on treatment for as long as they
continued to tolerate the drug and their disease did not progress. Efficacy
endpoints included CTC counts, serum PSA levels, soft tissue and bony
metastases, and time on treatment.

Results showed that MDV3100 was associated with anti-tumor activity
across a variety of endpoints in patients who had become resistant to
bicalutamide (Casodex(R))[1] or other standard anti-androgen treatments,
including patients who had failed prior chemotherapy (n=75) and those who
were chemotherapy-naïve (n=65). Anti-tumor activity was demonstrated by:

    - Substantial reductions in PSA levels, including declines in serum PSA
      of 50 percent or more in 56 percent of patients.

    - The PSA responses lasted for a median of 41 weeks for
      chemotherapy-naïve patients, 32 weeks for all patients and 21 weeks for
      post-chemotherapy patients.

    - Improvement or stabilization in tumors that had spread to soft tissue
      or bone. Treatment with MDV3100 was associated with tumor regressions
      (22 percent of all patients -- both chemotherapy-naïve and post-
      chemotherapy patients) and stable disease in soft tissue (49 percent of
      all patients) and stable disease in bone (56 percent of all patients).

    - The median time to radiographic progression was not reached for
      chemotherapy- naïve patients; it was 47 weeks in all patients combined
      and 29 weeks for post-chemotherapy patients.

    - A conversion from unfavorable to favorable CTCs in 49 percent of
      patients (75 percent of the chemotherapy-naïve and 37 percent of the
      post-chemotherapy groups). Of patients who initiated therapy with
      favorable counts, 91 percent retained favorable counts during
      treatment.

MDV3100 was generally well tolerated in the trial at doses up to and
including 240 mg/day. Fatigue was the most frequently reported adverse event.

"Based on the favorable benefit-risk ratio for MDV3100 observed in the
Phase 1-2 trial, we initiated the randomized, placebo-controlled Phase 3
AFFIRM trial in men with progressive advanced prostate cancer following
chemotherapy," said Lynn Seely, M.D., chief medical officer of Medivation.
"We also plan to evaluate MDV3100 in earlier stages of prostate cancer, as
those patients also are in need of new treatment options."

Phase 3 Trial of MDV3100 Underway

Medivation and Astellas are enrolling patients in a Phase 3 clinical
trial of MDV3100 in men with progressive disease following docetaxel
treatment. Known as AFFIRM, the randomized, placebo-controlled, double-blind,
multi-national trial has a primary endpoint of overall survival; secondary
endpoints include progression-free survival, safety and tolerability. The
AFFIRM study is being conducted at sites in Argentina, Austria, Australia,
Belgium, Canada, Chile, France, Germany, Italy, Netherlands, Poland, South
Africa, Spain, UK and U.S

About the Medivation/Astellas Collaboration

In October 2009, Medivation, Inc. entered into a global agreement with
Astellas Pharma Inc. to develop and commercialize MDV3100. The companies will
collaborate on a comprehensive development program that will include
additional studies to develop MDV3100 for both early- and late-stage prostate
cancer. Astellas is a recognized global category leader in the field of
urology, focusing its R&D and marketing resources in areas where there are
unmet medical needs. The company has developed pioneering treatments for
prostate cancer, benign prostatic hyperplasia and overactive bladder. Through
its commitment to research, support and understanding, the company continues
working to identify and develop innovative solutions for better patient
outcomes across the field of urology with a particular focus on broadening
its expertise and product delivery in oncology.

About MDV3100

MDV3100 is an investigational therapy in clinical development for the
treatment of advanced prostate cancer. The first triple-acting, oral androgen
receptor antagonist, MDV3100 has been shown in preclinical studies to provide
more compIete 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.

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. Prostate tumors that have stopped responding to, or are growing
despite the use of, active hormone treatment strategies are characterized as
castrate-resistant. Patients with castrate-resistant prostate cancer have a
poor prognosis and few treatment options.

About Astellas Pharma Inc.

Astellas Pharma Inc., located in Tokyo, Japan, is a pharmaceutical
company dedicated to improving the health of people around the world through
provision of innovative and reliable pharmaceuticals. Astellas has
approximately 15,000 employees worldwide. The organization is committed to
becoming a global category leader in Urology, Immunology & Infectious
Diseases, Neuroscience, DM complications & Metabolic Diseases and Oncology.
For more information on Astellas Pharma Inc., please visit our website at
www.astellas.com.

In Europe, Astellas is responsible for 20 affiliate offices located
across Europe, the Middle East and Africa, an R&D site and three
manufacturing plants. The company employs approximately 3,400 staff across
these regions.

Headquartered in Deerfield, Illinois, Astellas Pharma US, Inc. employs
more than 2,000 people in the U.S., Canada and Brazil.

About Medivation

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. In September 2008, Medivation announced a global agreement
with Pfizer, Inc to develop and commercialize dimebon (latrepirdine) for the
treatment of Alzheimer's and Huntington diseases. With Pfizer, Medivation is
conducting a broad dimebon clinical development program that includes several
Phase 3 trials assessing the efficacy and safety of dimebon taken alone or in
combination with other Alzheimer's medications in patients with mild,
moderate and severe Alzheimer's disease. The companies are also conducting a
Phase 3 trial of dimebon in Huntington disease. In October 2009, Medivation
entered a global agreement with Astellas Pharma Inc. to develop and
commercialize MDV3100 for both early- and late-stage prostate cancer. The
first Phase 3 clinical trial in the MDV3100 development program, known as the
AFFIRM trial, is under way in patients with castration-resistant prostate
cancer who have previously been treated with docetaxel-based chemotherapy.
For more information, please visit us at www.medivation.com.

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 Medivation's
product candidates, 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 Pfizer and
Astellas for the development of dimebon and MDV3100, respectively, including
the risk that Pfizer could elect to unilaterally terminate the dimebon
collaboration agreement with Medivation at its election at any time, the
achievement of development, regulatory and commercial milestones under
Medivation's collaboration agreements, manufacturing of Medivation's product
candidates, including Medivation's dependence on Pfizer for the manufacture
of all clinical requirements of dimebon, 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, 2009, filed on March 15,2010 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.

[1] Casodex is a registered trademark of the AstraZeneca group of
companies.

    Contacts:
    Medivation, Inc.
    Patrick Machado
    Chief Business Officer
    +1-415-829-4101

    WCG
    Bernadette Simmons
    bsimmons@wcgworld.com
    +44(0)7827-860309

Contacts: Medivation, Inc., Patrick Machado, Chief Business Officer, +1-415-829-4101; WCG: Bernadette Simmons, bsimmons at wcgworld.com, +44(0)7827-860309