SEATTLE, Sept. 20, 2017 /PRNewswire/ — PhaseRx, Inc. (NASDAQ: PZRX), a biopharmaceutical company developing mRNA treatments for life-threatening inherited liver diseases in children, today announced that its second drug development candidate, PRX-ASL, for the treatment of argininosuccinate lyase deficiency (ASLD), has received orphan drug designation by the U.S. Food and Drug Administration (FDA).
ASLD is a rare liver disorder caused by an inherited single-gene deficiency that results in hyperammonemia (elevated ammonia in the blood), and can lead to irreversible neurological impairment, coma and death. PRX-ASL is an intracellular enzyme replacement therapy (i-ERT) designed to replace the missing or defective enzyme in patients with ASLD, thereby correcting the disease. PRX-ASL has shown therapeutic potential in a preclinical model of ASLD, including reduction in the levels of compounds whose elevation are the hallmark of ASLD including plasma citrulline, argininosuccinic acid (ASA) and blood ammonia.
“The FDA’s decision to grant PRX-ASL orphan drug designation for ASLD represents an important milestone in the development of our second therapeutic candidate,” said Robert W. Overell, Ph.D., president and chief executive officer. “PRX-ASL is our second drug to show preclinical proof of concept using our Hybrid mRNA TechnologyTM. Like our lead candidate PRX-OTC, we believe PRX-ASL also has the potential to correct the disease in children, a population that could particularly benefit from treatment for this rare disease.”
The FDA grants orphan drug designation to investigational drugs and biologics that are intended for the treatment of rare diseases that affect fewer than 200,000 people in the U.S. Orphan drug status is intended to facilitate drug development for rare diseases and may provide several benefits to drug developers, including assistance with clinical study design and drug development, tax credits for qualified clinical trials costs, exemptions from certain FDA application fees, and seven years of market exclusivity upon regulatory product approval.
ASLD is a rare liver disorder caused by an inherited single-gene deficiency that results in hyperammonemia (elevated ammonia in the blood), and can lead to devastating consequences, including cumulative and irreversible neurological impairment, coma and death. The only cure for ASLD is a liver transplant. Currently available drug treatments do not correct the disease, and do not eliminate the risk of life-threatening crises.
PhaseRx is a biopharmaceutical company dedicated to developing mRNA products for the treatment of children with inherited enzyme deficiencies in the liver using intracellular enzyme replacement therapy (i-ERT). PhaseRx’s initial product development focus is on urea cycle disorders, a group of rare genetic diseases that generally present before the age of twelve and are characterized by the body’s inability to remove ammonia from the blood with potentially devastating consequences for patients. The company’s i-ERT approach is enabled by its proprietary Hybrid mRNA TechnologyTM platform. PhaseRx is headquartered in Seattle. For more information, please visit www.phaserx.com.