According to a story from Market Watch, the gene therapy company AVROBIO, Inc. has recently announced that its investigational gene therapy candidate AVR-RD-04 has earned Orphan Drug designation from the European Commission (EC). This gene therapy is being developed as a treatment for cystinosis, a rare disorder. AVR-RD-04 is currently in a phase 1/2 clinical trial. This experimental treatment consists of hematopoietic stem cells from the patient that have been genetically altered to express cystinosin, the protein that is lacking in people living with the condition.
Cystinosis is a type of lysosomal storage disease which is characterized by the abnormal accumulation of the amino acid cystine in the body. The disease is caused by mutations affecting the CTNS gene. This disease leads to the formation of cystine crystals in different areas of the body, particularly the cornea. Severe cystinosis can cause major symptoms early in life, such as kidney failure, growth and developmental impairments, diabetes, muscle atrophy, reduced skin and hair pigment, blindness, impaired sweating, and inability to swallow. Treatment of cystinosis includes cysteamine, which can impair the growth of crystals in the body; sodium citrate is also used to control blood acidity. If kidney failure occurs, dialysis and ultimately a kidney transplant are necessary for survival. To learn more about cystinosis, click here.
Orphan Drug Designation in the EU
In Europe, Orphan Drug designation is generally reserved for therapies being developed for an illness that is considered rare, which is defined as any disease that affects less than 5 in 10,000 people in the EU. Receiving this designation confers multiple benefits to the drug’s developer, such as research grants, reduced fees, assistance with clinical protocols, and a ten year period of market exclusivity if the drug is approved for use.
AVR-RD-04 has also earned Orphan Drug designation from the US Food and Drug Administration (FDA). The successful development of a gene therapy for cystinosis would herald a significant breakthrough in the treatment of this disease. While the symptoms of the illness can be managed, many patients may eventually face kidney failure and a reduced lifespan. Gene therapy could allow for greatly improved quality of life and treatment outcomes.