Completion of enrollment in phase III Orbit and Cosmic studies evaluating setrusumab (UX 143) for the treatment of osteogenesis imperfecta (OI)

The pivotal Phase III portion of the Orbit study has randomized 158 patients ages 5 to 25 years, and the Cosmic study has completed enrollment of 66 patients ages 2 to less than 7 years.

“We would like to thank the OI community for its support, trust and participation as we complete this important step in the advancement of the setrusumab program,” said Eric Crombez, M.D., chief medical officer at Ultragenyx. “The interim Phase II Orbit study results show a rapid and clinically meaningful decrease in fracture rate, giving us confidence in our ability to bring this potential new treatment to patients living with OI. Our goal is to provide patients and their families a novel treatment that can significantly reduce the burden of fractures and improve their quality of life by building new and stronger bone.”

Data presented at the American Society for Bone and Mineral Research 2023 Annual Meeting (ASBMR) from the Phase II portion of the Orbit study showed that treatment with setrusumab reduced the median annualized fracture rate by 67% and this reduction was associated with continuing large and meaningful improvements in bone mineral density (BMD). Setrusumab was generally well tolerated with no drug-related serious adverse events (SAEs) reported and no reports of drug-related hypersensitivity. Additional longer-term Phase II safety and efficacy data from the Orbit study are expected in the second half of 2024.

“From a clinical perspective the important thing is that we are potentially closer to the goal of having a treatment for children - including very young children - with osteogenesis imperfecta,” stated Nick Bishop, Professor of Paediatric Bone Disease at University of Sheffield Medical School. “The interim Phase II results are very encouraging, and the speed with which we have been able to complete recruitment into both the Orbit and Cosmic studies clearly reflects the positive views of the study clinicians as a whole regarding this investigational therapy.”