Leading Hematology Journal Publishes Pivotal ELOCTATE™ Data that Demonstrated Efficacy and Safety of Investigational Long

  Leading Hematology Journal Publishes Pivotal ELOCTATE™ Data that
  Demonstrated Efficacy and Safety of Investigational Long-Lasting Therapy for
  Hemophilia A

– Phase 3 Study Showed Potential for Once- or Twice-Weekly Prophylactic Dosing
                                  Regimens –

Business Wire

WESTON, Mass. & STOCKHOLM -- November 13, 2013

Today Biogen Idec (NASDAQ: BIIB) and Swedish Orphan Biovitrum AB(publ) (Sobi)
(STO: SOBI) announced that the detailed phase 3 data for the companies’
investigational long-lasting recombinant factor VIII Fc fusion protein
candidate ELOCTATE™ were published online in Blood, the journal of the
American Society of Hematology (ASH). Results from the A-LONG study showed
that people with severe hemophilia A may achieve effective prevention or
reduction of bleeding episodes with one or two prophylactic infusions a week.

ELOCTATE uses a technology called Fc fusion to prolong the time the therapy
circulates in the body, which may extend the time between prophylactic
infusions. If approved, ELOCTATE may enable people with severe hemophilia A to
receive fewer prophylactic infusions than the current standard of care.
Existing therapies require prophylactic infusions two to three times per week
or every other day, based on guidelines established by the Medical and
Scientific Advisory Council of the National Hemophilia Foundation. The A-LONG
study investigated ELOCTATE administered as individualized prophylactic
therapy (every three to five days with individual pharmacokinetics [PK]-guided
dosing adjustments) and as weekly prophylactic therapy. It also evaluated the
efficacy and safety of ELOCTATE used to treat bleeding episodes and to control
bleeding during surgery.

“There is an unmet medical need in the hemophilia community for longer
intervals between prophylactic infusions while maintaining good control of
bleeding episodes,” said Johnny Mahlangu, M.D., director of the Haemophilia
Comprehensive Care Centre, University of the Witwatersrand and National Health
Laboratory Service, Johannesburg, South Africa. “A-LONG is the first clinical
study to show that effective control over breakthrough bleeding may be
achieved with once- or twice-weekly prophylactic infusions in people with
severe hemophilia A.”

Hemophilia A is characterized by the substantial reduction, or absence of
functional levels of factor VIII, which impairs clotting and causes prolonged
periods of internal bleeding. To replace the missing clotting factor,
therapies can be infused on a regular schedule (prophylaxis), or after a
bleeding episode occurs (episodic or on-demand). Studies show people with
severe hemophilia who follow a prophylactic regimen experience fewer bleeding
episodes and their associated risks.^1,2,3,4,5

“Biogen Idec scientists have been researching long-lasting hemophilia
therapies for more than a decade, with the commitment to use innovative
science to develop therapies that we believe have the potential to transform
the standard of care,” said Glenn Pierce, M.D., Ph.D., senior vice president
of Global Medical Affairs and chief medical officer of Biogen Idec’s
hemophilia therapeutic area. “This study demonstrated the value of Fc fusion
technology in prolonging factor half-life to make less frequent prophylactic
infusions possible for people with hemophilia A.”

A-LONG Study Results

A-LONG was a global, open-label, multi-center phase 3 study that evaluated the
efficacy, safety and pharmacokinetics (PK) (measurement of the presence of the
drug in a patient’s body over time) of ELOCTATE in 165 male patients with
severe hemophilia A aged 12 years and older. The study involved 60 hemophilia
treatment centers in 19 countries on six continents.

The A-LONG study evaluated weekly and individualized prophylaxis to reduce or
prevent bleeding episodes, and episodic dosing to treat bleeding episodes. In
the individualized arm, each study participant’s PK parameters were used to
guide adjustments to dosing interval (from three to five days), and dose (25
to 65 IU/kg) to target a trough, or minimum, factor VIII level of 1–3 IU/dL or
higher as needed to maintain good control of breakthrough bleeding episodes.
The dose in the weekly prophylaxis arm was 65 IU/kg.

The median annualized bleeding rates (ABR), or projected number of yearly
bleeding episodes, was 1.6 in the individualized arm and 3.6 when ELOCTATE was
administered once weekly. People in the episodic treatment arm had an ABR of
33.6. ELOCTATE controlled more than 87 percent of bleeding episodes with a
single infusion, and physicians rated hemostatic response (the control and
prevention of a bleeding episode) as excellent or good in all (n=9) major
surgeries.

There were no drug-related serious adverse events, and noinhibitors
(neutralizing antibodies) were detected. Adverse events were representative of
events occurring in the general hemophilia population; the most common
(incidence of ≥5 percent) occurring outside of the perioperative period,
included nasopharyngitis (common cold), arthralgia (joint pain), headache and
upper respiratory infection.

“This study in Blood marks the first peer-reviewed publication to report
pivotal phase 3 results of a potential long-lasting therapy option for people
with hemophilia A,” said Birgitte Volck, M.D., Ph.D., senior vice president
development and chief medical officer of Sobi. “There is great interest among
the hemophilia community for options that have the potential to lessen the
frequency of prophylactic infusions necessary to prevent or reduce bleeding
episodes.”

Results of A-LONG were included in marketing applications in several
countries, including the United States, Canada and Australia.

About the Fc Fusion Technology Platform

ELOCTATE was developed using Fc fusion technology, which takes advantage of a
naturally occurring pathway that delays the breakdown of IgG1 protein in the
body by recycling it back into the bloodstream. This technology prolongs the
time ELOCTATE circulates in the body. While Fc fusion is an established
technology that has been used for more than 15 years, Biogen Idec is the only
company to apply it in hemophilia.

About Hemophilia A

Hemophilia A is a rare, genetic disorder in which the ability of a person's
blood to clot is impaired. Hemophilia A occurs in about one in 5,000 male
births annually, and more rarely in females, affecting about 16,000 people in
the U.S. It is caused by having substantially reduced or no factor VIII
activity, which is needed for normal blood clotting. People with hemophilia A
experience bleeding episodes that can cause pain, irreversible joint damage
and life-threatening hemorrhages. Prophylactic infusions of factor VIII can
restore the coagulation process, control bleeding, and prevent new bleeding
episodes.The Medical and Scientific Advisory Council of the National
Hemophilia Foundationrecommends prophylaxis as the optimal therapy for people
with severe hemophilia A.

About the Biogen Idec and Sobi Collaboration

Biogen Idec and Swedish Orphan Biovitrum (Sobi) are partners in the
development and commercialization of ELOCTATE for hemophilia A and ALPROLIX
for hemophilia B. Biogen Idec leads development, has manufacturing rights, and
has commercialization rights in North America and all other regions excluding
the Sobi territory. Sobi has the right to opt in to assume final development
and commercialization in Europe (including Russia), the Middle East and
Northern Africa.

AboutBiogen Idec

Through cutting-edge science and medicine,Biogen Idecdiscovers, develops and
delivers to patients worldwide innovative therapies for the treatment of
neurodegenerative diseases, hemophilia and autoimmune disorders. Founded in
1978,Biogen Idecis the world’s oldest independent biotechnology company.
Patients worldwide benefit from its leading multiple sclerosis therapies, and
the company generates more than$5 billionin annual revenues. For product
labeling, press releases and additional information about the company, please
visit www.biogenidec.com.

About Sobi

Sobi is an international specialty healthcare company dedicated to rare
diseases. Our mission is to develop and deliver innovative therapies and
services to improve the lives of patients. The product portfolio is primarily
focused on inflammation and genetic diseases, with three late stage biological
development projects within hemophilia and neonatology. We also market a
portfolio of specialty and rare disease products for partner companies. Sobi
is a pioneer in biotechnology with world-class capabilities in protein
biochemistry and biologics manufacturing. In 2012, Sobi had total revenues of
SEK 1.9 billion (€ 215 M) and about 500 employees. The share (STO: SOBI) is
listed on NASDAQ OMX Stockholm. More information is available at www.sobi.com.

Biogen Idec Safe Harbor

This press release contains forward-looking statements, including statements
about the potential advances, impact and therapeutic effect of ELOCTATE, our
investigational long-lasting recombinant factor VIII product candidate. These
statements may be identified by words such as "believe," "expect," "may,"
"plan," "potential," "will" and similar expressions, and are based on our
current beliefs and expectations. Drug development and commercialization
involve a high degree of risk. Factors which could cause actual results to
differ materially from our current expectations include the risk that
unexpected concerns may arise from additional data or analysis, regulatory
authorities may require additional data or information or further studies, or
may fail to approve or may delay approval of our drug candidates, or we may
encounter other unexpected hurdles. For more detailed information on the risks
and uncertainties associated with our drug development and commercialization
activities, please review the Risk Factors section of our most recent annual
or quarterly report filed with the Securities and Exchange Commission. Any
forward-looking statements speak only as of the date of this press release and
we assume no obligation to update any forward-looking statements, whether as a
result of new information, future events or otherwise.

^1 Nilsson IM, Berntorp E, Löfqvist T, Pettersson H. Twenty-five years'
experience of prophylactic treatment in severe haemophilia A and B. J Intern
Med 1992;232:25-32.

^2 Manco-Johnson MJ, Abshire TC, Shapiro AD, et al. Prophylaxis versus
episodic treatment to prevent joint disease in boys with severe hemophilia. N
Engl J Med 2007;357:535-44.

^3 Aledort LM, Haschmeyer RH, Pettersson H. A longitudinal study of
orthopaedic outcomes for severe factor-VIII-deficient haemophiliacs. The
Orthopaedic Outcome Study Group. J Intern Med 1994;236:391-9.

^4 Panicker J, Warrier I, Thomas R, Lusher JM. The overall effectiveness of
prophylaxis in severe haemophilia. Haemophilia : the official journal of the
World Federation of Hemophilia 2003;9:272-8.

^5 Nilsson IM, Hedner U, Ahlberg A. Haemophilia prophylaxis in Sweden. Acta
Paediatr Scand 1976;65:129-35.

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Contact:

BIOGEN IDEC CONTACTS:
Media Contact:
Todd Cooper, +1-781-464-3260
Senior Director, Public Affairs
or
Investor Relations Contact:
Ben Strain, +1-781-464-2442
Senior Manager, Investor Relations
or
SWEDISH ORPHAN BIOVITRUM CONTACTS:
Media Contact:
Oskar Bosson, +46 70 410 71 80
Head of Communications
or
Analyst/Investor Contact:
Jörgen Winroth, +1 347-224-0819, +1 212-579-0506, +46 8 697 2135
Vice President, Head of Investor Relations