Previously doing business as as REGENX Biosciences, LLC, the name of the firm was changed REGENXBIO Inc. in September 2014. REGENXBIO Inc., a clinical-stage biotechnology company providing gene therapy product candidates to deliver genes to cells to address genetic defects or to enable cells in the body to produce therapeutic proteins that are intended to impact disease. The firm's gene therapy product candidates are based on NAV Technology Platform, a proprietary adeno-associated virus (AAV) gene delivery platform. The company's lead product candidate is RGX-314 for the treatment of wet age-related macular degeneration. It is also developing RGX-501 for the treatment of homozygous familial hypercholesterolemia, which uses the AAV8 vector to deliver the human low-density lipoprotein receptor gene to liver cells; and RGX-111 to treat the neurological symptoms of Mucopolysaccharidosis Type I that uses the AAV9 vector to deliver the human a-l-iduronidase gene to the central nervous system (CNS). In addition, the company engages in the development of RGX-121 for the treatment of neurological symptoms of Mucopolysaccharidosis Type II, which uses the AAV9 vector to deliver the human iduronate-2-sulfatase gene to the CNS. Further, it licenses its NAV technology platform to other biotechnology companies. In 2013 ReGenX, along with Fidelity Biosciences, spun off Dimension Therapeutics to develop and commercialize products based off of technology developed by ReGenX. In August 217, REGENXBIO agreed to acquire rare metabolic disease-focused Dimension Therapeutics but in October 2107 was outbid by Ultragenyx Pharmaceutical Inc.