Developmental stage biotechnology company, Ultragenyx Pharmaceutical, has dosed the first two patients in a Phase 2 study of UX001, a drug designed for the treatment of patients with hereditary inclusion body myopathy (HIBM), a neuromuscular disease caused by sialic acid deficiency.

UX001, an extended-release oral tablet formulation of sialic acid (SA-ER), is intended for use as a substrate replacement therapy for HIBM.

The double-blind, international, multicentre, placebo-controlled parallel group and randomised study, which will enrol up to 45 patients between 18 and 65 years of age with a previously demonstrated mutation in the GNE gene causing HIBM, is designed to assess the safety and efficacy of UX001.

Patients will receive either of two dose levels of SA-ER or placebo over 24 weeks, with all patients continuing on active treatment after 24 weeks.

The study’s primary endpoint includes safety, whilst the pharmacodynamic endpoint will include improvements in sialylation biochemistry of muscle.

Clinical and patient-reported outcomes will also be assessed, but are not required for the study’s endpoints.

The Phase 2 study’s total duration is up to 48 weeks and data is expected to be obtained in 2013.

Ultragenyx CEO, Emil D Kakkis, said that the initiation of the Phase 2 study for HIBM patients follows from the positive results from the company’s Phase 1 trial.

"This Phase 2 study should help us determine if UX001 is improving the biochemistry of the muscle in these patients and help us learn more about the disease," Kakkis added.

"We look forward to seeing top line results next year."