Clinical-stage biotechnology company Ultragenyx Pharmaceutical has reported positive interim data from Phase II study of an oral sialic acid extended-release (SA-ER) tablet, UX001, in hereditary inclusion body myopathy (HIBM).
The 24-week interim data reported dose-dependent improvement in muscle strength compared to placebo in some muscle groups, especially in the upper extremities at the 6gm dose.
The changes, which were statistically significant or trended towards significance, were more distinct in subjects with greater walking ability at baseline, while no changes were observed in other clinical endpoints at the interim assessment.
Ultragenyx chief executive officer Emil Kakkis said that early data indicates a modest dose-dependent on an improvement in muscle strength in HIBM patients treated with UX001 compared to a decline in placebo-treated patients.
"We need to evaluate whether the observed treatment effect is sustained or increased over a longer 48-week period, and if higher dosing might further enhance the efficacy signal observed," Kakkis added.
According to the data, UX001 was well tolerated and 6gm dose group of the investigational agent showed a drift to improvement in creatine kinase levels compared to placebo.
Comparing the total daily doses of 6gm or 3gm of UX001, the Phase II study's primary objective is to evaluate safety, dose and potential pharmacodynamic effect of restoring sialylation of muscle in patients with a confirmed genetic mutation for HIBM.
Additionally, clinical measures of muscle strength, mobility, function, self-reported disability, and changes in quality of life are also being assessed.
Based on the dose-dependence observed at week 24, the company plans to treat patients in an extension study, following the 48-week analysis with an increased UX001 dosage.
The final 48-week data is anticipated by the end of 2013.