Across the world, various countries have Orphan Drug or Orphan Medicinal Product designations that leading agencies grant to products designed to treat patients with rare diseases. Recently, AVROBIO announced that its investigational treatment, AVR-RD-01, received Orphan Drug designation from the European Commission. The therapy is designed for patients with Fabry disease.
Ultimately, AVROBIO desires to create personalized gene therapy solutions for patients with rare conditions, from Fabry disease to Pompe disease. For the former, they developed AVR-RD-01. Many patients with Fabry disease are treatment-averse, experiencing disease progression even with treatments. However, AVR-RD-01 works to overcome this by using lentivirus vectors with hematopoietic stem cells (HSTs) taken directly from the patient.
According to GeneTherapy.net:
Lentivirus is a genus of the Retroviridae family, characterized by a long incubation period. Lentiviruses can deliver a significant amount of genetic information into the DNA of the host cell, so they are one of the most efficient methods of a gene delivery vector.
AVR-RD-01 is genetically engineered to deliver alpha-galactosidase A (a-Gal A) to patients. Since patients with Fabry disease have a lack of a-Gal A, the therapy prompts its expression. Ultimately, this helps to break down globotriaosylceramide and reduce symptoms.
In Europe, Orphan Drug designation is granted to products serving patients with rare conditions. These are defined as conditions affecting under 10,000 people in the EU. Drug developers who receive this designation also get 10 years of market exclusivity, grants for research, and low regulatory fees. In addition to receiving Orphan Drug designation in Europe, AVR-RD-01 also received the same designation in the United States.
Normally, our GLA gene produces and expresses a-Gal A. This breaks down a lipid called globotriaosylceramide. But in patients with Fabry disease, a genetic lysosomal storage disorder, there is a GLA mutation. As a result, patients have low levels of a-Gal A, contributing to a toxic buildup of globotriaosylceramide that usually begins in childhood. Symptoms intensify as patients age. Additionally, without treatment, symptoms can be fatal. Fabry disease affects 1 male out of every 40,000-60,000. While it may affect females, there is a lack of understanding on how many patients might be affected. Symptoms include:
- Hearing loss
- Gastrointestinal distress
- Nausea, vomiting, and diarrhea
- Chronic pain, particularly in the hands and feet
- Dull, cloudy vision
- Lack of ability to sweat
- Red spots or rashes on the skin
- Kidney and heart disease
Learn more about Fabry disease.