Biogen Idec and Sobi announce positive top-line efficacy and safety results from phase 3 Alprolix® paediatric study

  * Study Meets Primary Endpoint and Achieves Low Bleeding Rates with Once-
    Weekly Prophylactic Dosing in Children
  * Results Support EU Regulatory Submission and Future Paediatric Indication
    Applications

Biogen Idec (NASDAQ: BIIB) and Swedish Orphan Biovitrum AB (publ) (Sobi) (STO:
SOBI) today announced positive top-line results of the Kids B-LONG Phase 3
clinical study that evaluated the safety, efficacy and pharmacokinetics of
Alprolix® [Coagulation Factor IX (Recombinant), Fc Fusion Protein] in children
under age 12 with severe haemophilia B. Alprolix was generally well tolerated
and no inhibitors (neutralising antibodies that may interfere with the activity
of the therapy) were detected during the study. In this study, once-weekly
prophylactic dosing with Alprolix resulted in low bleeding rates. Alprolix is
the only approved hemophilia B therapy with prolonged circulation in the body.

The successful completion of Kids B-LONG supports applications for paediatric
indications in several geographies and is an important step in seeking marketing
authorisation for Alprolix in Europe. The European Medicines Agency requires the
inclusion of paediatric study data in the initial marketing application for a
new haemophilia therapy. Interim results of the Kids B-LONG study helped support
the U.S. approval of Alprolix for use in children.

"According to published studies, prophylactic treatment for children with severe
haemophilia is recommended because it is associated with proven clinical
benefits. However, frequent administration schedules can be burdensome for
children and their caregivers," said Aoife Brennan, M.D, vice president of
hematology clinical development at Biogen Idec. "These data will enable
regulatory filings in Europe later this year as well as support paediatric
indications in other countries, with the potential to help address a critical
need among children with haemophilia B."

Kids B-LONG investigated the safety, efficacy, and pharmacokinetics (measurement
of the presence of the drug in a person's body over time) of Alprolix in
previously treated children under age 12 with severe haemophilia B. The study's
primary endpoint was to evaluate the occurrence of inhibitor development.
Secondary endpoints included the overall and spontaneous annualised bleeding
rates (ABR), which is the estimated number of yearly bleeding episodes, and the
number of injections used to treat bleeding episodes.

In the study, children treated prophylactically with Alprolix had an overall
median ABR of 1.97. The median ABR for spontaneous joint bleeds was zero.
Approximately 33 percent of participants in the study experienced zero bleeding
episodes. Overall, 91.7 percent of bleeding episodes were controlled by one or
two injections of Alprolix. The terminal half-life of Alprolix in the study was
66.5 hours for children under six and 70.3 hours for children six to less than
12 years of age. Additional analyses of the Kids B-LONG study are ongoing, and
detailed results will be presented at a future scientific meeting.

No inhibitors to Alprolix were detected during the study. Alprolix was generally
well tolerated and no cases of serious allergic reactions or vascular thrombotic
events were reported in any participants, all of whom had been previously
treated with other commercially available factor IX products. No serious adverse
events were determined by any investigator to be related to the drug. One
adverse event, decreased appetite, was considered related to Alprolix treatment
and was reported in one participant. No participant discontinued the study due
to an adverse event after receiving Alprolix. The pattern of treatment-emergent
adverse events reported was consistent with the population studied and generally
consistent with results seen in adolescents and adults in the pivotal Phase 3 B-
LONG study.

"Sobi and Biogen Idec are committed to advancing treatment options for adults
and children with haemophilia," said Birgitte Volck, M.D., Ph.D., senior vice
president of development and chief medical officer at Sobi. "The completion of
Kids B-LONG marks an important milestone in the Alprolix development program. We
are excited to pursue the next stages of preparation for regulatory filing in
Europe and to potentially advance treatment options for people with haemophilia
B."

- - -

About Kids B-LONG
Kids B-LONG was a global, open-label, multicenter Phase 3 study involving 30
boys with severe haemophilia B (factor IX activity equal to or less than 2 IU
per dL, or 2 percent) with at least 50 prior exposure days to factor IX
therapies. The study was conducted at 16 haemophilia treatment centers in six
countries. Overall, 27 participants (90 percent) completed the study. The median
time participants spent in the study was 49.4 weeks, and 24 participants
received Alprolix injections on at least 50 separate days (exposure days).

About Alprolix
Alprolix® [Coagulation Factor IX (Recombinant), Fc Fusion Protein] is the only
approved recombinant, clotting factor IX therapy with prolonged circulation in
the body. In the United States, it is indicated for the control and prevention
of bleeding episodes, perioperative (surgical) management and routine
prophylaxis in adults and children with hemophilia B. Alprolix is not indicated
for immune tolerance induction therapy, which is a treatment for people with
inhibitors, and should not be used in individuals with a known history of
allergic reactions to Alprolix or any of the other ingredients in Alprolix.
Alprolix was developed by fusing factor IX to the Fc portion of immunoglobulin G
subclass 1, or IgG1 (a protein commonly found in the body). It is believed that
this enables Alprolix to use a naturally occurring pathway to prolong the time
the therapy remains in the body. While Fc fusion has been used for more than 15
years, Biogen Idec is the only company to apply it in hemophilia.

Common adverse reactions (incidence of greater than or equal to 1 percent) from
the B-LONG study were headache and oral paresthesia (an abnormal sensation in
the mouth). For complete prescribing information, go to www.alprolix.com.

Alprolix is also approved for the treatment of hemophilia B in Canada, Japan,
and Australia.

About Haemophilia B
Haemophilia B occurs in about one in 25,000 male births annually, and more
rarely in females, affecting about 6,300 people in the United States. The World
Federation of Hemophilia global survey conducted in 2012 estimates that
approximately 28,000 people are currently diagnosed with haemophilia B
worldwide. It is caused by having substantially reduced or no factor IX
activity, which is needed for normal blood clotting. People with haemophilia B
experience bleeding episodes that cause pain, irreversible joint damage and
life-threatening haemorrhages. Prophylactic injections of factor IX temporarily
replace clotting factors necessary to control bleeding and prevent new bleeding
episodes.

About the Sobi and Biogen Idec Collaboration
Sobi and Biogen Idec are collaborators in the development and commercialisation
of Alprolix for haemophilia B. Sobi has an opt-in right to take over exclusive
final development and commercialisation of Alprolix for the Sobi territories
(Europe, North Africa, Russia and certain Middle Eastern markets). Biogen Idec
leads development for Alprolix, has manufacturing rights, and has
commercialisation rights in North America and all other regions in the world
excluding the Sobi territory.

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 Haemophilia, Inflammation and Genetic diseases. We also market a
portfolio of specialty and rare disease products for partner companies across
Europe, the Middle East, North Africa and Russia. Sobi is a pioneer in
biotechnology with world-class capabilities in protein biochemistry and
biologics manufacturing. In 2014, Sobi had total revenues of SEK 2.6 billion
(USD 380 M) and about 600 employees. The share (STO: SOBI) is listed on NASDAQ
OMX Stockholm. More information is available at www.sobi.com.

About Biogen Idec
Through cutting-edge science and medicine, Biogen Idec discovers, develops and
delivers to patients worldwide innovative therapies for the treatment of
neurodegenerative diseases, hematologic conditions and autoimmune disorders.
Founded in 1978, Biogen Idec is the world's oldest independent biotechnology
company and patients worldwide benefit from its leading multiple sclerosis and
innovative hemophilia therapies. For product labeling, press releases and
additional information about the Company, please visit http://www.biogenidec.com

For more information please contact
Sobi
Media relations
Oskar Bosson, Head of Communications
T: +46 70 410 71 80
E: oskar.bosson@sobi.com

Investor relations
Jörgen Winroth, Vice President, Head of Investor Relations
T: +1 347-224-0819, +1 212-579-0506, +46 8 697 2135
E: jorgen.winroth@sobi.com

Biogen Idec
Media Contact
Lee-Ann Murphy
T: +1-781-464-3260
E: public.affairs@biogenidec.com

Investor Relations Contact:
Ben Strain
T: +1-781-464-2442
E: IR@biogenidec.com

Biogen Idec Safe Harbor
This press release contains forward-looking statements, including statements
about the potential and therapeutic impact of Alprolix. These forward-looking
statements may be accompanied by such words as "anticipate," "believe," "could,"
"estimate," "expect," "forecast," "intend," "may," "plan," "potential,"
"project," "target," "will" and other words and terms of similar meaning. You
should not place undue reliance on these statements. 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,
European regulatory authorities may require additional information or further
studies, or may fail to approve, or refuse to approve, or may delay approval of
our marketing authorization application for Alprolix, 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

[HUG#1898090]