Ultragenyx Pharmaceutical Inc. (RARE) on Monday said its Phase 3 Orbit and Cosmic studies evaluating setrusumab in Osteogenesis Imperfecta failed to meet their primary endpoints, sending the company's shares down more than 40% in pre-market trading.
Osteogenesis Imperfecta is a group of genetic disorders characterized by fragile bones that break easily.
In the pivotal Phase 3 portion of the Phase 2/3 Orbit study, patients were randomized to receive setrusumab or placebo, with the primary endpoint measuring the annualized clinical fracture rate. The study did not demonstrate a statistically significant benefit on this endpoint.
The Phase 3 Cosmic study also missed its primary goal. That trial assessed whether setrusumab could reduce the annualized fracture rate in children aged 2 to under 7 years, compared with standard bisphosphonate treatment.
Following the disappointing results, Ultragenyx said it is reviewing its planned operations and will implement significant cost-reduction measures.
Commenting on the outcome, Emil Kakkis, chief executive officer and president of Ultragenyx, said, "While we are disappointed by these results, we continue to build our commercial revenue from four approved products and prepare for a transformational year ahead with potentially two near-term gene therapy launches and a pivotal Phase 3 readout in Angelman syndrome."
Ultragenyx shares had closed at $34.19 on Friday, down 1.13%.
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