Edinburgh Clinical Trials


We will address the unmet clinical need for an effective, well-tolerated, and safe drug therapy for women with gestational diabetes, the most common pregnancy complication. Metformin IR (immediate release) is widely used as first-line drug therapy in the UK to control blood sugar levels and has significant advantages over other available drug therapies for women, including that it is a tablet and it helps limit pregnancy weight gain. However, standard metformin IR has poorly tolerated side effects including nausea and diarrhoea. It also freely crosses the placenta, and emerging evidence suggests potential for adverse child health outcomes including obesity. We plan to perform a three arm pilot proof-of-principle trial consisting of two non-randomised arms and one crossover randomised controlled arm involving 50 women using a new “delayed-release” (DR) metformin tablet which we hypothesise will substantially reduce levels of metformin in the mother’s blood and will reduce transfer of metformin across the placenta compared to metformin IR tablets, minimising the potential for adverse effects of metformin exposure for the child. We also aim to assess whether this metformin DR preparation compared to metformin IR is a feasible and acceptable alternative to other drug therapy for women with gestational diabetes and will have fewer side effects, which will encourage women to take their treatment regularly, thus improving their blood sugar control and avoiding the need for insulin injections. Our findings will support an application for a larger DR delayed-release as a treatment to optimise management of gestational diabetes with fewest side-effects for mother and baby.

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Chief Investigator: Professor Rebecca Reynolds

Number and location of participating sites (by region/ country): 2 UK Sites

EudraCT number: 2022-001240-24

ISRCTN number: ISRCTN12637839


Funder: CSO

Start and End date

Of grant award: 01 June 2022 - 30 November 2023

Of recruitment: 06 Sep 2023 (end date TBC)


Current Status: Recruiting


Sponsor: ACCORD  (https://www.accord.ed.ac.uk/)


Chief Investigator: Professor Rebecca Reynolds, Centre for Cardiovascular Science, University of Edinburgh, 47 Little France Crescent, Edinburgh, EH16 4TJ                                           

Email: r.reynolds@ed.ac.uk


Trial Manager: Anna Heye

Email: METAFOR.Trial@ed.ac.uk


Research Midwives: Shona Low and Sarah Donaldson

Email: slow@exseed.ed.ac.uk

Email: sdonald3@ed.ac.uk


ECTU involvement: Trial management / Statistics / Database.