Ultragenyx's Final Stage Study of Recombinant Human Beta-Glucuronidase Meets Primary Endpoint

Ultragenyx Pharmaceutical Inc.

revealed that its final stage study of recombinant human beta-Glucuronidase has met the primary endpoint of reduction in urinary CAG excretion. According to the company, the positive top line data from the pivotal study also provided proof of clinical improvement. It is an investigational therapy for the treatment of Mucopolysaccharidosis 7, i.e. MPS 7, Sly syndrome. Ultragenyx said that the trial demonstrated a reduction from baseline of 64.8 percent , i.e p<0.0001. The company added that the data would be presented at the 14th International Symposium on MPS and Related Diseases. The company indicated that based on these data, it intends to meet the FDA, as well as, the EMA in the current year to discuss its plans to submit regulatory filings in the first half of the next year. Ultragenyx CEO and President, Emil Kakkis, said, "Treatment with rhGUS showed a rapid and sustained reduction in urinary GAG excretion, as well as signs of clinical improvement in this heterogeneous patient population. We look forward to working with the FDA and EMA to file these data with the goal of bringing this potential treatment to patients with MPS7 who currently have no other options." The company disclosed that the trial offered proof of clinical improvement with rhGUS treatment. According to it, the Multi-domain Responder Index (MDRI) score at 24 weeks of treatment, which is a secondary endpoint, illustrated an overall mean improvement (±SD) of +0.5 domains (±0.80) (p=0.0527). Ultragenyx said that six of the 12 patients had an improvement in their MDRI score of +1 or more whereas five patients indicated no worsening of this progressive disease, or an MDRI score of 0. One patient had an MDRI score of -1. The company added that the MDRI is a summation of scores from different domains. The stock traded 2.34 percent higher in the extended hours of trading on Thursday.