A new drug being developed to treat Angelman syndrome (AS) has just been approved for ‘orphan drug’ status in the U.S., reports GlobeNewswire. The drug, called GTX-101, works by activating the paternal UBE3A gene to supress the symptoms of AS. Although there are not currently any approved treatments for AS, it is hoped that this new drug will provide patients with the first effective treatment option.
Angelman syndrome is a rare neuro-genetic disorder that causes intellectual and physical disability. AS tends to first become apparent in children around 6-12 months old, when they may have delayed development, such as not crawling or babbling. People with AS may go on to have symptoms including seizures, little speech, sleep disorders, difficultly moving, and issues with food, amongst others. Although it is rare for two people in a family to have AS, it is caused by genetic changes.
People usually carry two UBE3A genes, one from the mother and one from the father. In most areas of the body both genes are active, but in some areas of the brain only the maternal UBE3A gene is switched on. However, in over 80% of people with AS, the maternal UBE3A gene is either deleted (missing) or mutated (changed), leaving the child without an active copy of the gene in certain brain regions.
The drug, GTX-101, works by activating the paternal form of UBE3A to fulfill the role of the maternal UBE3A in certain brain areas where AS patients would otherwise not have an active form of UBE3A. This is known as a ‘targeted therapy’, because it treats the root cause of the symptoms, rather than the symptoms. The effectiveness of this treatment is supported by in vitro studies that show GTX-101 is effective at activating the paternal UBE3A in neurons from the central nervous system, an area affected by AS. Clinical trials using similar methodologies also show promising results for other neuro-genetic diseases including spinal muscular atrophy and amyotrophic lateral sclerosis.
GTX-101 will be further tested in clinical trials to assess its safety and effectiveness before it becomes available to patients. It is the first drug candidate produced by GeneTx Biotherapeutics LLC, a start-up that has collaborated with The Texas A&M University System and Texas A&M AgriLife Research to create GTX-101. The U.S. Food and Drug Administration’s decision to grant GTX-101 orphan-drug status will support the drug developers to help them bring the drug into commercial production. Orphan status is awarded to treatments that will help to cure ‘orphan’ diseases, rare and serious conditions that have limited treatment options. Benefits from this status include tax credits for clinical research, annual grant funding, help with clinical trials, a seven-year guarantee of marketing exclusivity if the drug is approved, and exemption from the Prescription Drug User Fee Act filing fees.
The new status of GTX-101 as an orphan drug will therefore provide support to the developers through the next stages of research before the drug is approved for widespread patient use in America.
The chief science officer at GeneTx, Allyson Berent, says that GTX-101 “represents a promising, novel approach to treat this devastating disorder.”