Ultragenyx to Present Setrusumab (UX143) at ASBMR 2024

Ultragenyx Pharmaceutical Inc. (NASDAQ: RARE), based in Novato, California, announced that it will present seven abstracts on its late-stage program evaluating setrusumab (UX143) and the treatment of osteogenesis imperfecta (OI) at the American Society for Bone and Mineral Research (ASBMR) 2024 Annual Meeting. This event will occur from September 27-30, 2024, in Toronto, Canada.

Eric Crombez, M.D., the Chief Medical Officer at Ultragenyx, emphasized the importance of this year's presentations, noting that they will add to the understanding of the real-world impact and burden of OI. Additionally, the phase 2 Orbit study results, initially announced in June, will be presented. These results demonstrate a substantial increase in bone mineral density and a corresponding decrease in the annualized fracture rate through month 14 of treatment with setrusumab.

The setrusumab presentations are as follows:

1. **Integrated Bone Biomarker Analyses**: This presentation will cover the mechanism of action of setrusumab in pediatric and young adult subjects with OI, and how these findings inform dose selection in the Orbit Study. This plenary poster (#Fri-423) will be displayed during the Welcome Reception and Plenary Poster Session on Friday, September 27 from 5:30 p.m. to 7:30 p.m. ET. Additionally, it will be featured in the Clinical Career Spotlight Rapid Fire session and Poster Session I on Sunday, September 29.

2. **Burden of Illness of Osteogenesis Imperfecta in Ontario, Canada**: This late-breaking poster (#Sat-LB 592) will discuss the burden of OI in Ontario and will be presented on Saturday, September 28 from 2:15 p.m. to 3:45 p.m. ET.

3. **Manifestations and Comorbid Conditions Among Patients with OI**: This poster (#Sat-447) will present a retrospective claims database analysis from the US on Saturday, September 28 from 2:15 p.m. to 3:45 p.m. ET.

4. **Fracture Rates for Patients with Osteogenesis Imperfecta**: This poster (#Sat-446) will present real-world data from US retrospective claims on fracture rates and will be displayed on Saturday, September 28 from 2:15 p.m. to 3:45 p.m. ET.

5. **Population Pharmacokinetics and PK/Pharmacodynamics Analyses**: This oral presentation (#1063) will discuss dose selection for the Phase 3 study of setrusumab in pediatric patients with OI, based on Phase 2 results from the Orbit Study. It will be presented on Sunday, September 29 from 11:45 a.m. to 12:00 p.m. ET.

6. **Healthcare Resource Use and Costs for Patients with OI**: This poster (#Sun-446) will present findings from US retrospective claims on healthcare resource utilization and associated costs. It will be featured on Sunday, September 29 from 2:15 p.m. to 3:45 p.m. ET.

7. **Sustained Reduction in Fracture Rate in Patients with OI Treated with Setrusumab**: This late-breaking oral presentation (#1125) will discuss the 14-month data from Phase 2 of the Phase 2/3 Orbit Study and will be presented on Monday, September 30 from 12:00 p.m. to 12:15 p.m. ET.

Osteogenesis Imperfecta (OI) is a group of genetic disorders affecting bone metabolism, primarily caused by mutations in the COL1A1 or COL1A2 genes. These mutations result in brittle bones and a high fracture rate among other complications. Currently, there are no globally approved treatments for OI, which affects approximately 60,000 people in commercially accessible regions.

Setrusumab (UX143) is a fully human monoclonal antibody that inhibits sclerostin, which negatively regulates bone formation. By blocking sclerostin, setrusumab aims to increase bone formation, mineral density, and bone strength. Preclinical studies in mouse models have shown promising results, including increased bone formation and improved bone strength.

Ultragenyx and Mereo BioPharma are collaborating on the global development of setrusumab, focusing on pediatric and young adult patients across various OI sub-types. This collaboration is grounded in a comprehensive late-stage development program.

Ultragenyx is a biopharmaceutical company dedicated to developing treatments for rare and ultra-rare genetic diseases. The company has a diverse portfolio of approved medicines and treatment candidates and aims to deliver safe and effective therapies swiftly and efficiently.