AMAG Pharmaceuticals Announces a Positive CHMP Opinion for the Approval of Ferumoxytol in Europe for the Treatment of Iron Deficiency Anemia in Adult Patients with Chronic Kidney Disease

European Approval and Commercial Launch Trigger $30 Million in
Milestones for AMAG

LEXINGTON, Mass., Apr 20, 2012 (BUSINESS WIRE) –AMAG Pharmaceuticals, Inc. (NASDAQ: AMAG) today announced that the
Committee for Medicinal Products for Human Use (CHMP) of the European
Medicines Agency (EMA) has issued a positive opinion for the approval of
ferumoxytol, an intravenous (IV) iron therapy, for the treatment of iron
deficiency anemia (IDA) in adult patients with chronic kidney disease
(CKD). In the European Union, ferumoxytol will be marketed as Rienso(R) by
AMAG’s partner, Takeda Pharmaceutical Company Limited.

“International expansion of ferumoxytol is an important growth
opportunity for AMAG,” said Frank Thomas, interim president and chief
executive officer of AMAG. “Following the approval of ferumoxytol in
Canada, which we received in late 2011, European approval would mark the
third region where ferumoxytol would be available for the treatment of
iron deficiency anemia in patients with CKD. Continued growth in our
U.S. CKD business, coupled with geographic expansion and the opportunity
to further expand the product’s label to include all patients with IDA,
would significantly enhance the growth prospects for ferumoxytol.”

European approval and the subsequent first commercial sale of
ferumoxytol in Europe would trigger $30 million in milestone payments to
AMAG from Takeda. Additionally, AMAG is entitled to receive tiered,
double-digit royalties on sales of ferumoxytol in licensed territories.
Upon EU Commission approval, Takeda is planning to launch Rienso in the
second half of 2012.

“Iron deficiency anemia can be a debilitating condition for chronic
kidney disease patients and appropriate management of this condition can
carry positive clinical implications for patients. Therefore, treatment
of anemia at all stages of CKD is important and the potential
availability of ferumoxytol in Europe would offer an additional
therapeutic option to help effectively manage this condition,” said
Professor Iain Macdougall 1, consultant nephrologist and
professor of clinical nephrology at King’s College Hospital, London.

Iron deficiency is a common cause of anemia in CKD patients, and is very
common in the later stages of CKD as renal function deteriorates and
erythropoiesis (red blood cell production) declines. IDA can have a
profound impact on patients’ lives, causing fatigue, shortness of breath
and an increase in the risk of cardiovascular complications including
congestive heart failure.2 IV iron is recommended for use to
increase hemoglobin levels in CKD patients with IDA and can also serve
to minimize the dose of ESA required to manage anemia in CKD. 2
Approximately one million grams of IV iron are administered to IDA
patients in the EU each year.

About AMAG Pharmaceuticals, Inc.

AMAG Pharmaceuticals, Inc. is a biopharmaceutical company that
manufactures and markets ferumoxytol under the brand name Feraheme(R) in
the United States. For additional company information, please visit

About Feraheme (ferumoxytol)

In the United States, Feraheme(R) (ferumoxytol) Injection for Intravenous
(IV) use is indicated for the treatment of iron deficiency anemia in
adult chronic kidney disease (CKD) patients. Feraheme received
marketing approval from the U.S. Food and Drug Administration on June
30, 2009 and was commercially launched by AMAG in the U.S. shortly
thereafter. Feraheme received marketing approval in Canada in
December 2011. For additional product information, please visit

AMAG Pharmaceuticals and Feraheme are registered trademarks of
AMAG Pharmaceuticals, Inc.

Rienso is a registered trademark of Takeda Pharmaceutical Company

1 Dr. Macdougall has been an investigator in clinical trials
of ferumoxytol sponsored by AMAG.

2 National Kidney Foundation. KDOQI clinical practice
guidelines and clinical practice recommendations for anemia in chronic
kidney disease. Am J Kidney Dis 2006;47(suppl 3):11-1458

The important safety information below is based on the United States
prescribing information.

Important Safety Information About Feraheme

Indication and contraindications

Feraheme is indicated for the treatment of iron deficiency anemia in
adult patients with chronic kidney disease. Feraheme is contraindicated
in patients with known hypersensitivity to Feraheme or any of its

Warnings and precautions

Serious hypersensitivity reactions, including anaphylactic-type
reactions, some of which have been life-threatening and fatal, have been
reported in patients receiving Feraheme.
Observe patients for
signs and symptoms of hypersensitivity during and after Feraheme
administration for at least 30 minutes and until clinically stable
following completion of each administration.
Only administer the
drug when personnel and therapies are immediately available for the
treatment of anaphylaxis and other hypersensitivity reactions.
Anaphylactic type reactions, presenting with cardiac/cardiorespiratory
arrest, clinically significant hypotension, syncope, and
unresponsiveness have been reported in the post-marketing experience.

In clinical studies, serious hypersensitivity reactions were reported in
0.2% (3/1,726) of subjects receiving Feraheme. Other adverse reactions
potentially associated with hypersensitivity (e.g., pruritus, rash,
urticaria or wheezing) were reported in 3.7% (63/1,726) of subjects.

Severe adverse reactions of clinically significant hypotension have
been reported in the post-marketing experience.
In clinical studies,
hypotension was reported in 1.9% (33/1,726) of subjects, including three
patients with serious hypotensive reactions. Monitor for signs and
symptoms of hypotension following each Feraheme injection. Excessive
therapy with parenteral iron can lead to excess storage of iron with the
possibility of iatrogenic hemosiderosis. Patients should be regularly
monitored for hematologic response during parenteral iron therapy,
noting that lab assays may overestimate serum iron and transferrin bound
iron values in the 24 hours following administration of Feraheme. As a
superparamagnetic iron oxide, Feraheme may transiently affect magnetic
resonance diagnostic imaging studies for up to 3 months following the
last Feraheme dose. Feraheme will not affect X-ray, CT, PET, SPECT,
ultrasound, or nuclear imaging.

Adverse reactions

In clinical trials, the most commonly occurring adverse reactions in
Feraheme treated patients versus oral iron treated patients reported in
greater-than or equal to 2% of chronic kidney disease patients were diarrhea (4.0% vs. 8.2%),
nausea (3.1% vs. 7.5%), dizziness (2.6% vs. 1.8%), hypotension (2.5% vs.
0.4%), constipation (2.1% vs. 5.7%) and peripheral edema (2.0% vs.
3.2%). In clinical trials, adverse reactions leading to treatment
discontinuation and occurring in 2 or more Feraheme treated patients
included hypotension, infusion site swelling, increased serum ferritin
level, chest pain, diarrhea, dizziness, ecchymosis, pruritus, chronic
renal failure, and urticaria.

Post-marketing safety experience

The following adverse reactions have been identified during
post-approval use of Feraheme. Because these reactions are reported
voluntarily from a population of uncertain size, it is not always
possible to reliably estimate their frequency or establish a causal
relationship to drug exposure.

The following serious adverse reactions have been reported from the
post-marketing spontaneous reports with Feraheme: life-threatening
anaphylactic-type reactions, cardiac/cardiorespiratory arrest,
clinically significant hypotension, syncope, unresponsiveness, loss of
consciousness, tachycardia/rhythm abnormalities, angioedema, ischemic
myocardial events, congestive heart failure, pulse absent, and cyanosis.
These adverse reactions have occurred up to 30 minutes after the
administration of Feraheme injection. Reactions have occurred following
the first dose or subsequent doses of Feraheme.

For full prescribing information, please visit

Forward Looking Statements

This press release contains forward-looking statements within the
meaning of the Private Securities Litigation Reform Act of 1995 and
other federal securities laws. Any statements contained herein which do
not describe historical facts, including but not limited to statements
regarding: the potential approval and potential commercial launch of
ferumoxytol/Rienso(R) in the EU, any milestone payments and royalties we
may receive following such approval and launch, the potential growth in
our US CKD business, geographic expansion, and the opportunity to
further expand the Feraheme label to include all patients with
IDA, and the potential for each of the foregoing to significantly
enhance the growth prospects for ferumoxytol, are forward-looking
statements which involve risks and uncertainties that could cause actual
results to differ materially from those discussed in such
forward-looking statements.

Such risks and uncertainties include: (1) the risk that
ferumoxytol/Rienso(R) does not receive final marketing approval in the EU
from the EMA, (2) uncertainties regarding our and Takeda’s ability to
successfully compete in the intravenous iron replacement market both in
the U.S. and outside the U.S., including the EU, (3) uncertainties
regarding our ability to successfully and timely complete our clinical
development programs and obtain regulatory approval for Feraheme in
the broader IDA indication both in the U.S. and in territories outside
of the U.S., including the European Union, (4) the fact that significant
safety or drug interaction problems could arise with respect to Feraheme,
(5) uncertainties regarding our ability to manufacture Feraheme,
(6) uncertainties relating to our patents and proprietary rights, and
(7) other risks identified in our Securities and Exchange
Commission filings, including our Annual Report on Form 10-K for the
year ended December 31, 2011. We caution you not to place undue reliance
on any forward-looking statements, which speak only as of the date they
are made.

We disclaim any obligation to publicly update or revise any such
statements to reflect any change in expectations or in events,
conditions or circumstances on which any such statements may be based,
or that may affect the likelihood that actual results will differ from
those set forth in the forward-looking statements.

SOURCE: AMAG Pharmaceuticals, Inc.

AMAG Pharmaceuticals, Inc.
Amy Sullivan, 617-498-3303