Gene Therapy and Hemophilia

Today, many clinical trials are underway to evaluate investigational gene therapy and its potential application for hemophilia. Learn more about how gene therapy is aimed at addressing genetic conditions like hemophilia at their source—the genes.

Explore the Science of Gene Therapy Research

See the science behind gene therapy research for hemophilia and how a vector is being studied to deliver a new functional gene to the cell that needs it.

“For more than 50 years, scientists have been investigating and evolving gene therapy, an approach that aims to address a genetic disease…”

“For more than 50 years, scientists have been investigating and evolving gene therapy, an approach that aims to address a genetic disease, such as hemophilia, at its source—the gene.

Genetic diseases can be caused by gene mutations—meaning the body does not have the instructions it needs to create the right proteins. Research is exploring whether a new, functional gene can be delivered into a cell to provide instructions to make a desired protein, such as factor VIII or IX in the case of hemophilia.

Together, let’s explore the science behind this investigational approach with our 3-D vector model. In gene therapy research, we need a way to get the functional gene into the body. A transporter, called a vector, is used.

Vectors are made from modified viruses. You may associate viruses with things that make you sick, but the most commonly used virus for hemophilia gene therapy research—the adeno-associated virus, or AAV—was chosen because it is not known to cause human disease.

A virus is transformed into a vector by removing the viral genetic information.

Now, the modified viral-based shell can serve as a delivery vehicle.

In a laboratory, the new functional gene is created. It contains the instructions for the cell to make a necessary protein such as factor VIII or IX.

Once created, the new functional gene is placed inside the shell. Together, they become a vector.

In hemophilia gene therapy research, the vector is delivered to the body by IV infusion into the blood. The goal is to deliver the new, functional gene to the liver cells, called hepatocytes.

Each viral vector has its own attraction, or tropism, to a certain cell type. In hemophilia, for example, AAV is attracted to the liver's cells. Once the vector reaches the liver, the new functional gene can enter a cell’s nucleus, or command center, where it sits next to the existing DNA.

If transferred successfully, the new gene instructs the liver cells to make the necessary protein. In the case of hemophilia, the gene enables the production of clotting proteins.

Safety and efficacy have not been established. Studies of investigational gene therapy are ongoing, and participants continue to be followed.

To learn more about gene therapy research for hemophilia, visit or talk with your healthcare team.”

“Por más de 50 años, los científicos han investigado y desarrollado la terapia génica, un enfoque que busca abordar una enfermedad genética, como la hemofilia, en su origen: el gen.”

“Por más de 50 años, los científicos han investigado y desarrollado la terapia génica, un enfoque que busca abordar una enfermedad genética, como la hemofilia, en su origen: el gen.

Las enfermedades genéticas pueden deberse a mutaciones genéticas, es decir, el cuerpo no tiene las instrucciones para crear las proteínas adecuadas. Se investiga si un nuevo gen funcional puede administrarse a una célula para proporcionar instrucciones para fabricar una proteína deseada, como el factor VIII o IX para la hemofilia.

Exploraremos la ciencia detrás de este enfoque de investigación con nuestro modelo de vector en 3D. En investigación de terapia génica, se necesita una forma de introducir el gen funcional al cuerpo. Se usa un transportador, llamado vector.

Los vectores son virus modificados. Quizá asocie los virus con cosas que le hacen enfermar, pero el virus más usado para la investigación de la terapia génica en hemofilia, el virus adenoasociado o AAV, fue elegido porque no se sabe que cause enfermedades humanas.

Un virus se transforma en un vector eliminando la información genética viral.

La cubierta de base viral modificada puede ser el vehículo de entrega.

El nuevo gen funcional se crea en un laboratorio. Contiene las instrucciones para que la célula produzca la proteína necesaria, como el factor VIII o IX.

Una vez creado, el nuevo gen funcional se coloca dentro de la cubierta. Juntos, se convierten en un vector.

En la investigación sobre la terapia génica de la hemofilia, el vector se introduce por infusión IV en la sangre. El objetivo es administrar el nuevo gen funcional a las células hepáticas, los hepatocitos.

Cada vector viral tiene su propia atracción a un determinado tipo de célula. En la hemofilia, por ejemplo, el AAV es atraído a las células hepáticas. Cuando el vector llega al hígado, el nuevo gen funcional puede ingresar al núcleo de una célula, donde se asienta junto al ADN existente.

Si se transfiere bien, el nuevo gen instruye a las células hepáticas para crear la proteína necesaria. En la hemofilia, el gen permite la producción de proteínas de coagulación.

La seguridad y la eficacia no se han establecido. Los estudios de terapia génica están en curso, y aún hay un seguimiento de participantes.

Para obtener más información sobre la investigación sobre terapia génica para la hemofilia, visite o hable con su equipo de atención médica.”

About gene therapy

Gene therapy is a potential approach to treating or preventing genetic conditions. The overall goal of investigational gene therapy is to deliver a functional gene to a specific, or target, cell. Once a functional gene is created, one approach is to insert it into a viral-based shell, creating a delivery package known as a vector.

Learn more about vectors, and review a step-by-step process of this delivery method.

The goals for gene therapy research in hemophilia

One approach investigational gene therapy for hemophilia is studying is a process designed to add a functional copy of the factor VIII or factor IX gene to the cell’s command center (nucleus). If transferred successfully, the functional gene is intended to provide the correct instructions for the cell to make factor VIII or factor IX clotting protein. The hope is to move from the highs and lows in clotting-factor levels (often called “peaks and troughs”) to a continuously expressed factor level.

Learn more about the one-time treatment goal.

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