Researchers at Children’s Hospital of Philadelphia (CHOP) found that emicizumab, a widely used drug for hemophilia A, could also improve blood clotting for select people with hemophilia B depending on their genes. The preclinical study, recently published in Blood, offers proof that this class of hemophilia A drug could potentially be used to treat hemophilia B.
Hemophilia is a genetic disorder in which blood doesn’t properly clot due to missing or low levels of certain proteins called “clotting factors,” which can lead to excessive bleeding. Hemophilia A, which is most common, is caused by a factor VIII (FVIII) deficiency, while hemophilia B results from a factor IX (FIX) deficiency. Traditionally, hemophilia was treated with intravenous factor replacement. However, hemophilia A treatment was revolutionized with the 2018 Food and Drug Administration (FDA) approval of emicizumab, a bispecific antibody that works by mimicking some of the biological functions of FVIII.
In contrast, hemophilia B still requires intravenous infusions of FIX. There are no current non-factor therapies in development that specifically target the deficiency in FIX activity. This study explores the interaction of emicizumab with hemophilia B-related FIX variants to understand their effect on the body’s blood clotting ability.
“Our research offers hope that these new treatments could eventually improve the quality of life for pediatric patients with select hemophilia B gene types, especially young children where intravenous administration is very challenging,” said Benjamin J. Samelson-Jones, MD, PhD, an attending physician in the Division of Hematology at CHOP. “We aim to help patients experience fewer complications and greater ease in managing their condition.”
In this study, researchers investigated specific FIX variants causing hemophilia B to determine whether they would help blood clot more effectively when combined with emicizumab. They screened 105 hemophilia B-causing FIX variants and found 41 variants that demonstrated improved clotting with emicizumab. They confirmed the results by similarly demonstrating improved clotting in patient samples.
“This study is an important example of how CHOP’s Frontier Programs are empowering us to transform pediatric healthcare,” said Samelson-Jones, a core member of the Novel Therapeutics for Bleeding Disorders (NoT Bleeding) Program team. “Our goal is to develop and deliver innovative therapies for hemophilia with a focus on safety and patient accessibility.”
This study was supported by the Frontiers Program at the Children’s Hospital of Philadelphia. Further research to confirm the safety and efficacy of the drug for hemophilia B patients is now supported by the National Institutes of Health.
Kyumin Lee, et al. “Enhanced procoagulant activity of select hemophilia B causing factor IX variants with emicizumab.” Blood. Online September 12, 2024. DOI: 10.1182/blood.2023021944.
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Researchers at Children’s Hospital of Philadelphia (CHOP) found that emicizumab, a widely used drug for hemophilia A, could also improve blood clotting for select people with hemophilia B depending on their genes. The preclinical study, recently published in Blood, offers proof that this class of hemophilia A drug could potentially be used to treat hemophilia B.
Hemophilia is a genetic disorder in which blood doesn’t properly clot due to missing or low levels of certain proteins called “clotting factors,” which can lead to excessive bleeding. Hemophilia A, which is most common, is caused by a factor VIII (FVIII) deficiency, while hemophilia B results from a factor IX (FIX) deficiency. Traditionally, hemophilia was treated with intravenous factor replacement. However, hemophilia A treatment was revolutionized with the 2018 Food and Drug Administration (FDA) approval of emicizumab, a bispecific antibody that works by mimicking some of the biological functions of FVIII.
In contrast, hemophilia B still requires intravenous infusions of FIX. There are no current non-factor therapies in development that specifically target the deficiency in FIX activity. This study explores the interaction of emicizumab with hemophilia B-related FIX variants to understand their effect on the body’s blood clotting ability.
“Our research offers hope that these new treatments could eventually improve the quality of life for pediatric patients with select hemophilia B gene types, especially young children where intravenous administration is very challenging,” said Benjamin J. Samelson-Jones, MD, PhD, an attending physician in the Division of Hematology at CHOP. “We aim to help patients experience fewer complications and greater ease in managing their condition.”
In this study, researchers investigated specific FIX variants causing hemophilia B to determine whether they would help blood clot more effectively when combined with emicizumab. They screened 105 hemophilia B-causing FIX variants and found 41 variants that demonstrated improved clotting with emicizumab. They confirmed the results by similarly demonstrating improved clotting in patient samples.
“This study is an important example of how CHOP’s Frontier Programs are empowering us to transform pediatric healthcare,” said Samelson-Jones, a core member of the Novel Therapeutics for Bleeding Disorders (NoT Bleeding) Program team. “Our goal is to develop and deliver innovative therapies for hemophilia with a focus on safety and patient accessibility.”
This study was supported by the Frontiers Program at the Children’s Hospital of Philadelphia. Further research to confirm the safety and efficacy of the drug for hemophilia B patients is now supported by the National Institutes of Health.
Kyumin Lee, et al. “Enhanced procoagulant activity of select hemophilia B causing factor IX variants with emicizumab.” Blood. Online September 12, 2024. DOI: 10.1182/blood.2023021944.
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