Gene therapy: Practical aspects of implementation.

Area of Science:

• Hepatology and Gene Therapy
• Hematology and Coagulation Disorders

Background:

• Gene therapies for haemophilia utilize liver-directed recombinant adeno-associated viral vectors (rAAV) to deliver functional Factor VIII (FVIII) or Factor IX (FIX) genes.
• These therapies involve a single treatment event where rAAV vectors are taken up by liver cells, delivering DNA for FVIII/FIX expression and secretion.

Purpose of the Study:

• To review best practices for managing gene therapy in haemophilia patients.
• To address challenges in clinical care models and infrastructure for haemophilia treatment centers (HTCs).
• To optimize outcomes and ensure durable transgene expression with liver-directed gene therapy.

Main Methods:

• Review of current gene therapy approaches for haemophilia using rAAV vectors.
• Analysis of immune responses, specifically elevations in liver enzymes, post-infusion.
• Discussion of strategies for managing potential liver toxicity and the need for immunosuppression.

Main Results:

• Gene therapy has shown efficacy in the majority of individuals treated.
• Immune responses (elevated liver enzymes) require diligent monitoring post-infusion.
• Immunosuppression is sometimes necessary but often avoidable or short-lived.

Conclusions:

• Optimal outcomes depend on pre-therapy screening, liver health maintenance, and close follow-up.
• Immunomodulatory strategies are crucial for managing liver toxicity and preserving transgene expression.
• Adapting traditional clinical care models and HTC infrastructure is essential for successful gene therapy implementation.