EMA Initiates Accelerated Review for Bluebird's Gene Therapy Targeting Rare Disease CALD

EMA Accelerates Review of Lenti-D for CALD Treatment

The European Medicines Agency (EMA) has initiated an accelerated review process for Bluebird bio's gene therapy, Lenti-D (elivaldogene autotemcel or eli-cel), aimed at treating cerebral adrenoleukodystrophy (CALD). CALD is the most severe form of adrenoleukodystrophy (ALD), a neurodegenerative disease that predominantly affects boys in early childhood, leading to physical and mental disabilities as well as behavioral issues.

Impact of CALD and the Need for Effective Treatments

Cerebral ALD affects approximately one in 17,000 live births, with around 40% of ALD patients developing this severe form. The disease is caused by mutations in the ABCD1 gene on the X chromosome, which is crucial for producing the ALD protein necessary to clear toxic very long-chain fatty acids (VLCFAs) from the brain. The accumulation of VLCFAs damages the myelin sheath, leading to the disease's devastating effects.

Lenti-D: A Promising Gene Therapy

Lenti-D works by modifying the patient's own stem cells to produce a functional version of the ABCD1 gene, thereby enabling the production of ALD protein and the clearance of VLCFAs. This innovative approach offers a potential one-time treatment for CALD, contrasting with the current standard of care, which involves stem cell transplants. While stem cell transplants can halt disease progression, they require high-dose chemotherapy and carry significant risks, including graft-versus-host disease.

Clinical Trial Results and Future Prospects

Recent data from the phase 2/3 STARBEAM trial revealed that 87% of CALD patients treated with Lenti-D were alive and free of major functional disabilities after at least two years of follow-up. Bluebird bio is also conducting the phase 3 ALD-104 trial, with results expected in 2024. The company plans to file for approval of Lenti-D in the US by mid-next year, following delays due to the COVID-19 pandemic.

Expert Commentary

Gary Fortin, head of severe genetic disease programmes at Bluebird, emphasized the significance of Lenti-D: "CALD is a devastating disease, often marked by rapid neurodegeneration, the development of major functional disabilities, and eventual death. If approved, eli-cel would represent the first therapy for CALD that uses a patient’s own haematopoietic stem cells, potentially mitigating the risk of life-threatening immune complications associated with transplant using cells from a donor."

Conclusion

The accelerated review by the EMA marks a critical step forward in the potential approval of Lenti-D, offering hope for a transformative treatment for CALD patients. As the medical community awaits further trial results and regulatory decisions, the promise of gene therapy continues to shine as a beacon of hope for those affected by rare and severe genetic diseases.