Treatment With Prolia(R) (denosumab) Associated With Significantly Greater Adherence, Compliance and Persistence Compared to Alendronate

New 2-Year Open-Label Study Shows More Than 90 Percent of Patients Preferred Prolia Injection Every Six Months Over Weekly Oral Alendronate

THOUSAND OAKS, California, March 23, 2011 - Amgen (Nasdaq: AMGN) today announced new data that showed postmenopausal
women with osteoporosis had significantly greater adherence, compliance, and
persistence during Prolia(R) (denosumab) treatment than during alendronate
treatment, an oral bisphosphonate commonly used to treat osteoporosis.

Adherence to treatment, which includes both compliance (a measure of how
well patients follow directions for taking medication) and persistence (a
measure of whether patients continue with treatment), was measured over two
years.

Results from the DAPS (Denosumab Adherence Preference and Satisfaction)
study presented at the annual European Congress on Osteoporosis and
Osteoarthritis (ECCEO11-IOF) in Valencia, Spain, also found that more than 90
percent of patients preferred Prolia as a treatment option over alendronate.
In addition, significantly more patients were satisfied with denosumab
injection compared with alendronate tablet (mean score of 4.5 vs. 3.2; score
scale of 1-5, higher score, higher satisfaction, p<0.0001).

"Despite the availability of several treatment options, many
postmenopausal women with osteoporosis are not taking their medication as
prescribed and therefore remain at risk for fractures," said Professor Nick
Freemantle, University of Birmingham, Birmingham, UK. "Prolia is an important
treatment option for patients not only because of its efficacy and safety,
but also because, as this study suggests, women may be more likely to stay on
treatment compared to weekly oral alendronate."

DAPS Study Results

DAPS was a two-year, multicenter, open-label, crossover study of 250
postmenopausal women with a bone mineral density (BMD) T-score of less than
or equal to -2.0 to greater than or equal to -4.0 at the lumbar spine, total
hip, or femoral neck and no prior bisphosphonate treatment. Patients were
randomized (1:1) to receive either Prolia every six months in year 1 followed
by weekly oral alendronate in year 2, or receive alendronate in year 1
followed by Prolia in year 2.

In the study, 92.4 percent of the patients preferred Prolia over
alendronate versus 7.6 percent who preferred alendronate (p<0.0001).
Additionally, 91.2 percent preferred Prolia as a treatment option versus 8.8
percent for alendronate (p<0.0001), and overall significantly more patients
were more satisfied with treatment with Prolia compared to treatment with
oral alendronate.

In patients who received Prolia in the second year of the study,
treatment with Prolia compared to alendronate was associated with
significantly greater:

    - adherence (92.5 percent vs. 63.5 percent, p<0.0001),
    - compliance (93.4 percent vs. 67.8 percent, p<0.0001), and
    - persistence (97.2 percent vs. 71.3 percent, p<0.0001) with treatment.

Patients were considered adherent to treatment if they received two
Prolia injections within 6 months (plus or minus 4 weeks) apart, or took
greater than or equal to 80 percent weekly oral alendronate and at least two
alendronate tablets in the last month, and returned for the final study visit
within an allotted time.

The incidence and types of adverse events (AEs) and serious adverse
events (SAEs) were generally similar between the Prolia and alendronate
patient groups. SAEs were reported in 3.5 percent and 3.9 percent of patients
receiving Prolia and alendronate, respectively.

Osteoporosis: Impact, Prevalence and the Role of Adherence

Referred to as a "silent epidemic" by the International Osteoporosis
Foundation (IOF), osteoporosis is a global problem that is increasing in
significance as the population of the world both increases and ages. The
World Health Organization has officially declared osteoporosis a public
health crisis, and the IOF is urging governments worldwide to make
osteoporosis a healthcare priority.

Osteoporosis-associated fractures are a significant cause of mortality
and morbidity. In 2000, the number of osteoporotic fractures in Europe was
estimated at 3.79 million, of which 890,000 were hip fractures.(1) Since
2001, the incidence of hip fractures in European countries has risen
significantly.(2) In the United States (U.S.), the number of fractures due to
osteoporosis is expected to rise to more than three million by 2025.(3)

The direct medical cost of osteoporotic fractures in Europe is expected
to rise from euro 31.7 billion in 2000 to euro 76.7 billion in 2050.(4) In
2005, osteoporosis-related fractures were responsible for an estimated $19
billion in cost in the U.S., and this cost is expected to rise to
approximately $25 billion by 2025.(5)

Postmenopausal women with osteoporosis who have experienced a fracture
are at increased risk for another fracture.(6),(7),(8) Poor adherence can
increase fracture risk and has been associated with more fracture-related
hospitalizations.(9) Yet globally, adherence to osteoporosis treatments
remains low.

    - An analysis of data combined over multiple U.S. health plans showed
      that approximately 50 percent of patients discontinue oral
      bisphosphonate therapy within the first year.(10)
    - Data from the UK Health Improvement Network and General Practice
      Research Database showed that less than 50 percent of women in the UK
      continue osteoporosis therapy after six months.(11)
    - In Germany, the IMS(R) Disease Analyser database showed that compliance
      with medication helped reduce the risk for fracture, yet only one third
      of women in the database were still on treatment after one year.(12)

About Prolia

Prolia is the first approved therapy that specifically targets RANK
Ligand, an essential regulator of osteoclasts (the cells that break down
bone).

Prolia is approved in the European Union (EU) for the treatment of
osteoporosis in postmenopausal women at increased risk of fractures, and for
the treatment of bone loss associated with hormone ablation in men with
prostate cancer at increased risk of fractures.

Prolia is approved in the U.S. for the treatment of postmenopausal women
with osteoporosis at high risk for fracture, defined as a history of
osteoporotic fracture, or multiple risk factors for fracture; or patients who
have failed or are intolerant to other available osteoporosis therapy.

Prolia is available in 12 European countries, the U.S., Canada and
Australia. Applications in the rest of the world are pending.

Prolia is administered as a single subcutaneous injection of 60mg once
every six months. For further information on Prolia, please visit:
www.prolia.com.

Important EU Safety Information

The most common adverse reactions with Prolia were urinary tract
infection, upper respiratory tract infection, sciatica, cataracts,
constipation, rash, pain in extremity. The most serious adverse reactions
were those of skin infections, predominantly cellulitis, reported more
commonly in the Prolia group compared with placebo (0.4 percent vs. 0.1
percent) in postmenopausal osteoporosis studies. In breast and prostate
cancer studies, serious adverse reactions of skin infection were similar in
the Prolia and placebo groups (0.6 percent vs. 0.6 percent). In the Phase 3
placebo-controlled clinical trial in patients with prostate cancer receiving
ADT, an imbalance in cataract adverse events was observed with Prolia
compared with placebo (4.7 percent vs. 1.2 percent placebo). No imbalance in
cataract adverse events was observed in postmenopausal women with
osteoporosis or in women undergoing aromatase inhibitor therapy for
nonmetastatic breast cancer.

Prolia may lead to hypocalcaemia. Hypocalcaemia must be corrected by
adequate intake of calcium and vitamin D before initiating therapy.
Osteonecrosis of the jaw (ONJ) has been reported rarely in clinical studies
in patients receiving denosumab at a dose of 60 mg every 6 months for
osteoporosis.

Important U.S. Safety Information

Prolia is contraindicated in patients with hypocalcemia. Pre-existing
hypocalcemia must be corrected prior to initiating Prolia. Hypocalcemia may
worsen, especially in patients with severe renal impairment. All patients
should be adequately supplemented with calcium and vitamin D.

In the pivotal study, serious infections leading to hospitalizations were
reported more frequently in the Prolia-treated patient group. Serious skin
infections, as well as infections of the abdomen, urinary tract and ear, were
more frequent in patients treated with Prolia. Patients should be advised to
seek prompt medical attention if they develop signs or symptoms of severe
infection, including cellulitis. Endocarditis was reported more frequently in
the Prolia-treated patient group. Epidermal and dermal adverse events such as
dermatitis, rashes, and eczema have been reported. Discontinuation of Prolia
should be considered if severe symptoms develop.

Prolia resulted in significant suppression of bone remodeling. The
significance of these findings is unknown. The long-term consequences of the
degree of suppression of bone remodeling observed with Prolia may contribute
to adverse outcomes such as ONJ, atypical fractures, and delayed fracture
healing. ONJ has been reported in patients with Prolia. Patients should be
monitored for these adverse outcomes. The most common adverse reactions (> 5
percent and more common than placebo) were back pain, pain in extremity,
musculoskeletal pain, hypercholesterolemia, and cystitis. Pancreatitis has
also been reported with Prolia.

Denosumab Commercialization Collaborations

In July 2009, Amgen and GlaxoSmithKline announced a collaboration
agreement to jointly commercialize Prolia for postmenopausal osteoporosis in
Europe, Australia, New Zealand and Mexico once the product is approved in
these countries. Amgen will commercialize Prolia's postmenopausal
osteoporosis and potential oncology indications in the U.S. and Canada and
for all oncology indications in Europe and in other specified markets.

In addition, GlaxoSmithKline will register and commercialize denosumab
for all indications in countries where Amgen does not currently have a
commercial presence, including China, Brazil, India and South Korea but
excluding Japan. The structure of the collaboration allows Amgen the option
of an expanded role in commercialization in both Europe and certain emerging
markets in the future.

Amgen and Daiichi-Sankyo Company Limited have a collaboration and license
agreement for the development and commercialization of denosumab in Japan.

About Amgen

Amgen discovers, develops, manufactures, and delivers innovative human
therapeutics. A biotechnology pioneer since 1980, Amgen was one of the first
companies to realize the new science's promise by bringing safe, effective
medicines from lab to manufacturing plant to patient. Amgen therapeutics have
changed the practice of medicine, helping millions of people around the world
in the fight against cancer, kidney disease, rheumatoid arthritis, bone
disease, and other serious illnesses. With a deep and broad pipeline of
potential new medicines, Amgen remains committed to advancing science to
dramatically improve people's lives. To learn more about our pioneering
science and vital medicines, visit www.amgen.com.

Forward-Looking Statements

This news release contains forward-looking statements that are based on
management's current expectations and beliefs and are subject to a number of
risks, uncertainties and assumptions that could cause actual results to
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of historical fact, are statements that could be deemed forward-looking
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    CONTACT:
    Amgen, Thousand Oaks
    Ashleigh Koss: +1-805-313-6151 (media)
    Wendy Woods Williams: +41(41)3692-542 (E.U. media)
    Arvind Sood: +1-805-447-1060 (investors)

(1) "Facts and statistics about osteoporosis and its impact."
International Osteoporosis Foundation. Accessed at
www.iofbonehealth.org/facts-and-statistics.html#factsheet-category-22
on 4 February 2011

(2) "Osteoporosis in the European Union in 2008: Ten years of progress
and ongoing challenges." Accessed at
www.iofbonehealth.org/publications/eu-policy-report-of-2008.html on 4
February 2011

(3) Burge R, et al. Incidence and economic burden of osteoporosis-related
fractures in the United States, 2005-2025. J Bone Miner Res. 2007:
22::465-475

(4) "Facts and statistics about osteoporosis and its impact."
International Osteoporosis Foundation. Accessed at
www.iofbonehealth.org/facts-and-statistics.html on 4 February 2011

(5) "Fast Facts" National Osteoporosis Foundation. Accessed at
www.nof.org/node/40 on 4 February 2011

(6) Kanis JA et al. A Meta-Analysis of Previous Fracture and Subsequent
Fracture Risk. Bone. 2004;35(2):375-82.

(7) Lindsay R et al. Risk of new vertebral fracture in the year following
a fracture. JAMA. 2001 Jan 17;285(3):320-33.

(8) Klotzbuecher CM et al. Patients with prior fractures have an
increased risk of future fractures: a summary of the literature and
statistical synthesis. J Bone Miner Res. 2000 Apr;15(4):721-39.

(9) Siris ES et al. Adherence to bisphosphonate therapy and fracture
rates in osteoporotic women: relationship to vertebral and nonvertebral
fractures from 2 US claims databases. Mayo Clin Proc. 2006 Aug;81(8):1013-22.

(10) Weycker D. et al. Compliance with drug therapy for postmenopausal
osteoporosis. Osteoporos Int. 2006;17(11):1645-52. Epub 2006 Jul 22.

(11) Li L, Roddam A, Gitlin M, Taylor A, Shepherd S, Jick S.
Retrospective Analysis of Persistence to Anti-Osteoporosis Medications in the
UK General Practice Research Database (GPRD). Poster P606. Presented at IOF
WCO-ECCEO 2010

(12) Hadji P, Claus V, Steinle T, Kostev K, Intorcia M. Non-adherence in
women with osteoporosis treated with oral bisphosphonates: German
Retrospective cohort Analysis on Non-aDherence (GRAND). Poster P604.
Presented at IOF WCO-ECCEO 2010

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Media: Ashleigh Koss, +1-805-313–6151; E.U. Media: Wendy Wood Williams, +41(41)3692-542; Investors: Arvind Sood, +1-805-447-1060