Ultragenyx Initiates Phase 1 Clinical Study of UX001 in Hereditary Inclusion Body Myopathy (HIBM), a Rare Muscle Wasting Disease

NOVATO, Calif., Aug. 15, 2011 /PRNewswire/ -- Ultragenyx Pharmaceutical Inc., a biotechnology company focused on developing treatments for rare and ultra-rare genetic disorders, today announced the dosing of the first patient in a Phase 1 study of UX001 for hereditary inclusion body myopathy (HIBM). UX001 is an extended release formulation of sialic acid intended as a substrate replacement therapy for HIBM, a severe, progressive, genetic neuromuscular disease caused by sialic acid deficiency. UX001 is the first program from the company's pipeline to enter the clinic since its founding in 2010.

"Advancing UX001 to the clinic is an important milestone for both Ultragenyx and for patients suffering with HIBM," said Emil D. Kakkis, MD, PhD, Chief Executive Officer of Ultragenyx. "HIBM is one of many rare diseases that lack treatment, but for which good science exists on how it might be treated. Ultragenyx's goal is to be a leader in rare disease therapeutics by rapidly and efficiently transforming existing science into effective treatments for rare diseases that have been neglected in the past."

The Phase 1 clinical study will evaluate the pharmacokinetics (PK) and safety of UX001 in 24 HIBM patients at two centers in New York and Los Angeles. The study will test four different single-dose levels in each group of six subjects. Subjects will then undergo repeat dosing at three dose levels over 7 days to establish the steady-state pharmacokinetics and safety of repeat doses of UX001.  Ultragenyx anticipates data from the Phase 1 study in late 2011.

About HIBM and UX001

HIBM, which is also known as distal myopathy with rimmed vacuoles (DMRV) and Nonaka disease, is a severe, adult-onset muscle disease caused by a defect in an enzyme responsible for the first step of sialic acid biosynthesis.  With deficiency of this enzyme, the patient's muscles are deficient in sialic acid needed for the synthesis of proteins and fats. Patients with HIBM typically begin to have weakness and abnormal walking at 18 to 30 years of age. Over the ensuing 10 to 20 years, many patients progressively lose significant functional ability and become wheelchair-bound. There are no current treatments for HIBM.

UX001 is an extended release formulation of sialic acid that should allow the maintenance of steady levels of sialic acid after oral administration. The sialic acid replacement therapy is expected to restore the proper biochemistry of glycoproteins and glycolipids by allowing proper sialylation.  Data from an HIBM mouse model show a profound beneficial effect of sialic acid replacement therapy on the biochemistry, pathology and clinical outcomes of HIBM mice.

About Ultragenyx

Ultragenyx is a private, clinical-stage biotechnology company committed to developing life-enhancing therapeutics for patients with rare and ultra-rare genetic diseases. Ultragenyx is leveraging its experience in orphan indications to identify target diseases with well understood biological mechanisms to generate a pipeline of promising treatments for medically underserved patient populations. Ultragenyx' lead program, UX001, is currently being evaluated in a Phase 1 trial in hereditary inclusion body myopathy (HIBM).

Ultragenyx aspires to create a new model for successful rare disease drug development and to deliver significant value to all its key stakeholders by rapidly and efficiently transforming good science into great medicines for untreated rare diseases. Ultragenyx' investors include TPG Biotech and Fidelity Biosciences, HealthCap and Pappas Ventures. The company is led by Emil Kakkis, MD, PhD, a recognized industry leader in rare disease research and development.

For more information on Ultragenyx, please visit the company's website at www.ultragenyx.com.

SOURCE Ultragenyx Pharmaceutical Inc.