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CSL Behring Presents Pivotal Efficacy Data for AFSTYLA® In Adolescents and Children with Hemophilia A at the World Federation of Hemophilia 2016 World Congress
CSL Behring today presented data from a Phase III pivotal study of AFSTYLA® [Antihemophilic Factor (Recombinant), Single Chain] in hemophilia A patients less than 12 years of age at the XXXII International Congress of the World Federation of Hemophilia (WFH) in Orlando, Fla.
  • AFSTYLA prophylaxis and on-demand treatment demonstrated long-lasting hemostatic efficacy in pediatric patients with severe hemophilia A in phase III data presented
  • Patients using AFSTYLA prophylactically were well-controlled across treatment regimens – including twice weekly dosing
  • AFSTYLA achieved safe and effective perioperative hemostasis in a wide range of surgeries
  • AFSTYLA demonstrates CSL’s 100-year promise to develop and deliver medical innovations that improve patients’ lives

CSL Behring today presented data from a Phase III pivotal study of AFSTYLA® [Antihemophilic Factor (Recombinant), Single Chain] in hemophilia A patients less than 12 years of age at the XXXII International Congress of the World Federation of Hemophilia (WFH) in Orlando, Fla. The results showed that AFSTYLA, used prophylactically across different treatment intervals (including two to three times weekly), achieved low annualized spontaneous bleeding rates (median AsBR of 0.00) and low annualized bleeding rates (median ABR of 3.69) in previously treated children and adolescents with hemophilia A. Overall, the efficacy of AFSTYLA to treat bleeding events in patients on prophylaxis or on-demand regimens was rated as excellent or good by investigators in 96.3 percent of all bleeding events (total of 347 treated events).

“The results show that AFSTYLA provided robust protection to both prevent and manage bleeds in children and adolescents with hemophilia A,” said Professor Ingrid Pabinger-Fasching, M.D., of the Medical University of Vienna, Austria, and lead investigator of the study. “AFSTYLA fills an important need for the pediatric hemophilia A community, helping to meet their treatment challenges and offering an opportunity for excellent efficacy with a strong safety profile and more convenient dosing.”

The study was part of the Phase I/III AFFINITY clinical program, which included two completed pivotal studies and one ongoing open-label, multicenter extension study evaluating the safety and efficacy of AFSTYLA in children, adolescents, and adults with hemophilia A. The current study results reported at WFH included data on more than 5,200 exposure days in previously treated pediatric patients with severe hemophilia A (factor VIII levels <1%). Patients had more than 50 previous exposure days to factor VIII products prior to enrollment. During the study, patients received either prophylactic (n=81) or on-demand (n=3) treatment with AFSTYLA according to WFH dosing recommendations. The median time on study was 5.6 months. Among patients in the prophylaxis group, 54 percent were dosed twice weekly, and 30 percent were dosed three times weekly. The most common adverse reactions were nasopharyngitis (common cold), arthralgia (joint pain), cough, and headache. There were no serious adverse events, and no patients developed inhibitors while receiving AFSTYLA.

AFSTYLA is the first and only single-chain product for hemophilia A specifically designed for long-lasting protection from bleeds with two to three times weekly dosing. AFSTYLA was approved by the U.S. Food and Drug Administration (FDA) in May for use in children and adults with hemophilia A for routine prophylaxis to reduce the frequency of bleeding episodes; on-demand treatment and control of bleeding episodes; and the perioperative management of bleeding. Regulatory agencies in Europe, Switzerland, and Australia are currently reviewing CSL Behring’s license applications for AFSTYLA.

Additional AFSTYLA Data Presented at WFH

In a separate presentation (Poster #108), researchers shared results on the efficacy and safety of AFSTYLA given as continuous or intermittent bolus infusion during surgery in two studies in the AFFINITY clinical development program. The data included 18 patients with severe hemophilia A whom underwent a total of 21 major surgeries (defined as a procedure requiring general, spinal or regional anesthesia) including a wide range of general, dental and orthopedic procedures. Investigators rated the efficacy of AFSTYLA as excellent or good in 100 percent of the surgeries (19 procedures rated as excellent; 2 procedures rated as good). The results were consistent regardless of the infusion method. No adverse events or serious adverse events were observed during any procedure.

At WFH, investigators also presented the effects of an intensified prophylaxis regimen with AFSTYLA (50 IU/kg three times weekly) that was prescribed by the investigator to eradicate a pre-existing low titer inhibitor in a patient enrolled in the pediatric study (Poster #89). The individual had approximately 27 exposure days to factor VIII therapy in the year prior to enrollment and about 100 exposure days overall. He was enrolled into the study with a pre-existing low-titer inhibitor that was not reported at screening. The results showed that the patient’s inhibitor titer continuously decreased, dropping below the cut-off for positivity (<0.6 BU/mL) after three months and remaining negative through the end of the study. In addition, all bleeding episodes (total of seven treated) were well-controlled with AFSTYLA. The patient continues to be treated with prophylactic AFSTYLA in the extension study.

“For 100 years CSL has developed and delivered innovative treatments for patients with serious medical conditions and, today, we are pleased to present at the WFH 2016 World Congress new AFSTYLA data from our AFFINITY clinical development program,” said Dr. Andrew Cuthbertson, Chief Scientific Officer and Director of R&D, CSL Limited. “The collective results build upon previous data demonstrating the efficacy of this innovative therapy for routine prophylaxis, on-demand treatment and perioperative bleeding management in hemophilia A. As the first and only FDA-approved single-chain recombinant factor VIII product, AFSTYLA delivers improved protection from bleeding with less frequent dosing and has an excellent safety profile.”

About Hemophilia A

Primarily affecting males, hemophilia A is a congenital bleeding disorder characterized by deficient or defective factor VIII. People with hemophilia A 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 (CDC), the condition affects approximately 1 in 6,000 male births.


AFSTYLA (also known as rVIII-Single Chain) for hemophilia A is CSL Behring’s recombinant single-chain factor VIII specifically designed for greater molecular stability and longer duration of action. AFSTYLA uses a covalent bond that forms one structural entity, a single polypeptide-chain, to improve the stability of factor VIII and provide longer-lasting factor VIII activity.

For more information about AFSTYLA, including full prescribing information in the U.S., please visit

U.S. Only: AFSTYLA Important Safety Information

AFSTYLA®, Antihemophilic Factor (Recombinant), Single Chain, is indicated in adults and children with hemophilia A (congenital factor VIII deficiency) for:

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

AFSTYLA is not indicated for the treatment of von Willebrand disease.

AFSTYLA is contraindicated in patients who have had life-threatening hypersensitivity reactions to AFSTYLA or its excipients, or to hamster proteins.

AFSTYLA is for intravenous use only. AFSTYLA can be self-administered or administered by a caregiver with training and approval from a healthcare provider or hemophilia treatment center.

Higher and/or more frequent dosing may be needed for patients under 12 years of age.

Hypersensitivity reactions, including anaphylaxis, are possible. Advise patients to immediately report symptoms of a hypersensitivity reaction. If symptoms occur, discontinue AFSTYLA and administer appropriate treatment.

Development of factor VIII (FVIII) neutralizing antibodies (inhibitors) can occur. If expected factor VIII activity levels are not attained or bleeding is not controlled with appropriate dose, perform an assay to measure factor VIII inhibitor concentration.

Monitor plasma factor VIII activity using a chromogenic assay or one-stage clotting assay. In the U.S., if one-stage clotting assay is used, multiply result by a conversion factor of 2 to determine factor VIII activity level.

The most common adverse reactions (>0.5%) reported in clinical trials were dizziness and hypersensitivity.

About CSL Behring

CSL Behring is a global biotherapeutics leader which is 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 more than 16,000 people with operations in more than 30 countries. For more information about CSL Behring visit or follow us at



Greg Healy
CSL Behring
Office: 610-878-4841
Mobile: 610-906-4564

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