Agilis Biotherapeutics, a Cambridge-based biotechnology company, announced that the U.S. FDA has granted Orphan Drug Designation to AGIL-AS, its gene therapy product candidate being developed for the treatment of Angelman syndrome (AS).  AGIL-AS is being investigated as a new therapeutic to treat AS by delivering a corrective UBE3A gene to rescue neurological deficits in patients suffering from this rare disease. This is the first drug to be granted an Orphan Drug Designation status by the U.S. FDA for the indication of AS.  AS is a rare neuro-genetic disorder characterized by severe intellectual and developmental disability.  It is caused by the deletion/mutation of the UBE3A gene which encodes the ubiquitin ligase E6-AP, a protein which plays a critical role in the function of the central nervous system.  According to The Foundation for Angelman Syndrome Therapeutics (FAST), the disorder strikes an estimated 1 in 15,000 live births.
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http://www.agilisbio.com/wp-content/uploads/2015/11/Angelman-ODD-Press-Release-11-4-2015-Final.pdf