Gene Therapy Research in Hemophilia

Hemophilia is a result of a change in a single gene, affecting the production of factor protein. Gene therapy is designed to increase factor by delivering a working copy of the gene.

Currently, hemophilia is most commonly treated with frequent injections or infusions. Gene therapy research is aimed at finding a potential one-time or infrequent treatment as an additional treatment option to replace ongoing treatments for hemophilia. 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.

Current factor therapy for hemophilia

Graph illustrating typical peak and trough levels for someone taking factor treatment.

Aim: continuously expressed factor level

Chart illustrating a continuous, steady factor level.

Graphics are illustrative examples.

Goals for gene therapy research in hemophilia

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The primary research goal is the safety and effectiveness in reducing bleeding rates.

Secondary goals can include the effectiveness of addressing other areas such as joint health and the number of infusions.

Investigational gene therapy for hemophilia is designed to add a functional copy of the factor VIII or factor IX gene to a cell’s command center (nucleus). If transferred successfully, the functional gene is intended to provide the cell with the instructions to make factor VIII or factor IX clotting protein.

In this case, a virus is used as the delivery vehicle, or vector. First, the viral genetic information is removed. The new DNA (functional gene) is placed inside the viral-based shell, which can carry the new gene into the body. The vector is delivered into the body via intravenous (IV) infusion into the blood.

The vector used in hemophilia gene therapy research has a preference for targeting liver cells (hepatocytes).

Have questions about gene therapy research and clinical trials?

Investigational Gene Therapy’s Potential Application for Hemophilia

What is a vector? See how gene therapy research is aiming to treat hemophilia by delivering a new functional copy of a gene into the cell by a vector.

“Today, many clinical trials are underway to evaluate investigational gene therapy and its potential application for hemophilia.”

“Today, many clinical trials are underway to evaluate investigational gene therapy and its potential application for hemophilia. The goal of this research is to evaluate a transition in the treatment experience—aiming to move from recurrent treatment interventions with highs and lows in clotting-factor levels to a potential single or infrequent intervention. The idea is to move to a continuously expressed factor level, with the hope of preventing spontaneous bleeding episodes.

The goal of investigational gene therapy is to address hemophilia at its source—the gene. One approach being studied is to deliver a new, functional copy of a gene into the cell by a vector, with the aim of producing blood-clotting factors.

You might be wondering, “What is a vector?” A vector is a modified virus. By removing the viral genetic information, the new functional gene can be placed inside the viral-based shell for transport. Once delivered into the body by IV infusion, the vector can travel to its target—the liver cells. If transferred into liver cells successfully, the new functional gene is intended to provide the correct instructions for making FVIII or FIX clotting protein.

Safety and efficacy have not been established. Studies of investigational gene therapy are ongoing, and participants continue to be followed. So, it is important to speak with your healthcare team, ask questions, and be informed.

Explore the science of gene therapy research at”

“Hoy día, hay muchos ensayos clínicos para evaluar la terapia génica investigativa y su posible aplicación para la hemofilia.”

“Hoy día, hay muchos ensayos clínicos para evaluar la terapia génica investigativa y su posible aplicación para la hemofilia. El fin de la investigación es evaluar una transición en el tratamiento: pasar de intervenciones recurrentes de tratamiento con altibajos en los niveles del factor de coagulación a una posible intervención única o infrecuente. La idea es pasar a un nivel de factor expresado continuamente, con la esperanza de prevenir sangrados espontáneos.

El fin de la terapia génica investigativa es tratar la hemofilia en su origen, el gen. Un enfoque es introducir una nueva copia funcional de un gen en la célula mediante un vector, con el fin de producir factores de coagulación.

Quizás se pregunte: “¿Qué es un vector?” Un vector es un virus modificado. Al eliminar la información genética viral, este gen funcional puede colocarse dentro de la cubierta de base viral para su transporte. Una vez administrado en el cuerpo por infusión intravenosa, el vector puede ir hasta su objetivo, las células hepáticas. Si se transfiere a las células hepáticas con éxito, se espera que el nuevo gen funcional dé instrucciones correctas para fabricar la proteína de coagulación factor VIII o IX.

No se han establecido la seguridad y la eficacia. Los estudios de terapia génica están en curso, y aún hay un seguimiento de participantes. Por lo que es importante que hable con su equipo médico. Haga preguntas y esté informado.

Explore la ciencia de la investigación sobre terapia génica en”

Frequently asked questions

Other techniques are being investigated to treat or prevent disease at the genetic level. Here are 3 approaches to gene therapy:

Gene transfer, the main gene therapy approach discussed on this site, introduces new genetic material into cells.

Gene editing, sometimes called genome editing or genomic editing, modifies existing genes in a person’s DNA to correct specific mutations.

Cell therapy transplants whole cells capable of adding a new or desired function into a person.

Currently, gene transfer therapy is the approach being most broadly investigated in hemophilia.

Learn more about these gene therapy approaches.

Gene therapy has been studied for over 50 years; however, most gene therapies are still in the research phase. Even for gene therapies that have been approved, patients will be monitored to document the safety and durability of the treatment.

Learn more about the clinical trial process.

Wondering if a clinical trial could be right for you or a loved one?



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