Edinburgh Clinical Trials


Treatment of Osteogenesis Imperfecta with Parathyroid hormone and Zoledronic acid

TOPaZ is a randomised open-label clinical trial for people with osteogenesis imperfecta (OI). The study aims to investigate whether a two-year spell of treatment with a drug called teriparatide (TPTD) followed by treatment with another drug called Zoledronic acid (ZA) reduces the risk of broken bones occurring in people with OI.


Chief Investigator: Prof. Stuart Ralston

Number and location of participating sites (by region/ country): 25 UK, Republic of Ireland, France, Netherlands, Denmark

EudraCT number: 2016-003228-22

ISRCTN number: 15313991

Funder: NIHR Efficacy and Mechanism Evaluation Programme


Start and End date:

Of grant award - Nov 2016-April 2025

Of recruitment - Oct 2022


Current Status: In follow up


Trial Website: The TOPaZ Trial


UK GDPR Privacy Statement: If you have participated in this study and would like to read how it complies with UK GDPR, please read this document.


Sponsor: ACCORD http://www.accord.ed.ac.uk/

Chief Investigator: Professor Stuart Ralston, Molecular Medicine Centre, Institute of Genetics and Cancer, Western General Hospital, Edinburgh, EH4 2XU

Trial manager: topaz.trial@ed.ac.uk


ECTU Involvement: Trial management / Statistics / Database and randomisation service provision.


TOPaZ study logo