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IDELVION® Newly Approved 3500 IU Vial to Provide Convenience to Patients Using Larger Volumes
• IDELVION 14-day dosing option for some patients, combined with the larger vial size, will improve convenience with fewer vials and less infusions • New vial option delivers on CSL Behring’s promise to enhance current treatments and provide more alternatives to patients
KING OF PRUSSIA, Pa. – 31 May 2018 – Global biotherapeutics leader CSL Behring today announced that the US Food and Drug Administration (FDA) has approved a 3500 IU (international unit) vial size for IDELVION® [Coagulation Factor IX (Recombinant), Albumin Fusion Protein (rFIX-FP)], its novel, long-acting recombinant albumin fusion protein for treating hemophilia B.  For some patients requiring high doses of IDELVION, the 3500 IU vial size will reduce the reconstitution time needed to prepare multiple vials for a similar dose. IDELVION is the first and only FDA-approved factor IX therapy that delivers zero median AsBR (annualized spontaneous bleeding rate) and is approved for up to 14-day dosing in appropriate patients.  When used prophylactically, IDELVION has been shown to elevate factor IX levels to 21% at steady state.

“Having a variety of vial sizes available for patients, particularly larger vials, increases convenience for patients in optimizing their administration regimen,” said Craig Kessler, MD, Director, Division of Coagulation and Director of the Hemophilia and Thrombosis Comprehensive Care Center, Georgetown University Medical Center. “The 3500 IU vial can be helpful for patients currently on IDELVION or those who might have been waiting until more convenient vial sizes were available in order to begin treatment with IDELVION.”

“We believe a good portion of the community will benefit from the addition of this fifth, larger vial to the IDELVION family,” adds Jerry Powell, MD, Coagulation Medical Director, North America, CSL Behring.  “Reconstituting the same amount of factor from a single vial will require less diluent than reconstituting multiple vial sizes, saving patients time and ancillary supplies.”

In the clinical trial, IDELVION delivered high factor IX levels of 21% at steady state with prophylactic use and 5% over 14 days with one single dose.  IDELVION is currently available in 250 IU, 500 IU, 1000 IU, and 2000 IU, with the 3500 IU vial to be available for order in the coming weeks. 

About Hemophilia B

Hemophilia B is a congenital bleeding disorder characterized by deficient or defective factor IX; nearly all affected patients are male. People with hemophilia B may experience prolonged or spontaneous bleeding, especially into the muscles, joints, or internal organs. According to the U.S. Centers for Disease Control and Prevention, the condition occurs in approximately one in 25,000 male births.


CSL Behring engineered IDELVION to extend the half-life of recombinant factor IX through fusion with recombinant albumin. CSL Behring selected recombinant albumin as its fusion partner for its coagulation factor proteins due to its long physiological half-life.  IDELVION is approved in the United States, Australia, Canada the European Union and Japan.

For more information about IDELVION, including full prescribing information, please visit For more information about CSL Behring's recombinant products in development to treat hemophilia, visit

Important Safety Information

IDELVION®, Coagulation Factor IX (Recombinant), Albumin Fusion Protein (rFIX-FP), is indicated in children and adults with hemophilia B (congenital Factor IX deficiency) for:

  • On-demand treatment and control of bleeding episodes
  • Perioperative management of bleeding
  • Routine prophylaxis to reduce the frequency of bleeding episodes

IDELVION is not indicated for induction of immune tolerance in patients with hemophilia B.

IDELVION is contraindicated in patients who have had life-threatening hypersensitivity to the product or its components, including hamster proteins.

IDELVION is for intravenous use only. IDELVION can be self-administered or administered by a caregiver with training and approval from a healthcare provider or hemophilia treatment center. Higher dose per kilogram body weight or more frequent dosing may be needed for pediatric patients.

Hypersensitivity reactions, including anaphylaxis, are possible. Advise patients who self-administer to immediately report symptoms of hypersensitivity, including angioedema, chest tightness, hypotension, generalized urticaria, wheezing, and dyspnea. If symptoms occur, discontinue IDELVION and administer appropriate treatment.

Development of neutralizing antibodies (inhibitors) to IDELVION may occur. If expected Factor IX activity plasma levels are not attained or bleeding is not controlled with appropriate dose, perform an assay to measure Factor IX inhibitor concentration. Factor IX activity assay results may vary with the type of activated partial thromboplastin time reagent used.

Thromboembolism (eg, pulmonary embolism, venous thrombosis, and arterial thrombosis) can occur when using Factor IX-containing products. In addition, nephrotic syndrome has been reported following immune tolerance induction in hemophilia B patients with Factor IX inhibitors and allergic reactions to Factor IX.

The most common adverse reaction (incidence ≥1%) reported in clinical trials was headache.

Please see full prescribing information for IDELVION.

About CSL Behring

CSL Behring is a global biotherapeutics leader driven by its promise to save lives. Focused on serving patients’ needs by using the latest technologies, we develop and deliver innovative therapies that are used to treat coagulation disorders, primary immune deficiencies, hereditary angioedema, inherited respiratory disease, and neurological disorders. The company's products are also used in cardiac surgery, organ transplantation, burn treatment and to prevent hemolytic disease of the newborn.

CSL Behring operates one of the world's largest plasma collection networks, CSL Plasma. The parent company, CSL Limited (ASX:CSL), headquartered in Melbourne, Australia, employs nearly 20,000 people, delivering its life-saving therapies to people in more than 60 countries. For more information visit and follow us on

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Media Contact
Jennifer Purdue
Office: +1 610 878 4802         Mobile: +1 610 306 9355       


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