Northern Ireland Clinical Research Network’s Endocrinology and Diabetes Team contribute to TOPaZ Published Research

June 2, 2026

Teriparatide Plus Zoledronic Acid for Osteogenesis Imperfecta (TOPaZ) study was published in the Journal of the American Medical Association (JAMA) on May 14th 2026. The Northern Ireland Clinical Research Network (NICRN), part of the Belfast trust, has contributed to this important international study, which explored new treatments for the rare brittle bone condition called Osteogenesis Imperfecta (OI).

The TOPaZ trial involved randomising 350 adults through 27 referral centres across the UK and Europe, including the Belfast Health & Social Care Trust. The study investigated whether using the bone-building drug teriparatide followed by zoledronic acid could reduce fractures in adults living with OI.

This randomised controlled trial (RCT) found that teriparatide plus zoledronic acid did not reduce fracture risk compared with standard care despite significantly increasing bone mineral density, suggesting the importance of reduced bone quality rather than low bone density in the pathogenesis of fracture.

This study is one of the largest RCTs ever conducted in adults with OI and highlights the importance of collaborative clinical research in rare diseases. The results will help guide future research and support the development of more targeted treatments for patients living with this lifelong condition.

NICRN would like to say a massive thank you to the Principal Investigator Dr John Lindsay, Clinical Research Co-ordinators Charlotte and Deslyn, and the Belfast Trust staff involved in the study for their valuable contributions and support.