Gene Therapy for Haemophilia A

Source: TH

Context: Researchers has achieved a milestone by conducting a successful gene therapy trial for severe haemophilia A using a lentivirus vector.

Gene Therapy for Haemophilia A:

What is Haemophilia A?

• Definition: A hereditary bleeding disorder caused by the deficiency of clotting Factor VIII.

• Genetic Cause: It arises due to a defective gene on the X chromosome.

• Prevalence: More common in males; females are typically carriers.

Symptoms

• Prolonged Bleeding: Following injury or surgery.

• Spontaneous Bleeding: Internal bleeding in joints and muscles without apparent cause.

• Bruising: Unusual or frequent bruises.

• Hemarthrosis: Bleeding into joints, causing pain and swelling.

What is Replacement Therapy?

• Definition: A standard treatment where clotting factors are injected into the veins to replace the deficient Factor VIII.

• Mechanism: Derived from human plasma or produced synthetically (recombinant clotting factors).

• Challenges: Short lifespan of clotting factors in the body. Antibodies may neutralize the clotting factors, reducing effectiveness.

• Short lifespan of clotting factors in the body.

• Antibodies may neutralize the clotting factors, reducing effectiveness.

What is Roctavian?

• Definition: The first FDA-approved gene therapy for severe haemophilia A.

• How It Works: Uses an adeno-associated virus (AAV) vector to deliver a corrected gene encoding Factor VIII. The gene integrates into liver cells to produce clotting Factor VIII.

• Uses an adeno-associated virus (AAV) vector to deliver a corrected gene encoding Factor VIII.

• The gene integrates into liver cells to produce clotting Factor VIII.

• Efficacy: Reduces annual bleeding rates but requires corticosteroids to suppress immune reactions.

• Limitations: Treatment response may wane over time, and pre-existing antibodies to AAV may limit its use.

Lentivirus Vector in Gene Therapy:

• Advantages: Rarely triggers pre-existing Integrates into host cells, ensuring long-term production of clotting factors.

• Rarely triggers pre-existing

• Integrates into host cells, ensuring long-term production of clotting factors.

• Indian Approach: Gene transfer into adult stem cells for lifelong efficacy.

Insta Links:

• Haemophilia-A