Clinical scientists at the Garvan Institute of Medical Research are seeking participants for a Phase 3 clinical trial to test a drug that could slow the process of cognitive decline, a hallmark of the processes that may lead to dementia. 

The three-year intervention study will examine the effects of metformin – a drug used to treat diabetes and other metabolic disorders – on cognition, brain anatomy, vascular health and early signs of dementia.  

“We are building on promising research on the positive effects of metformin that could have real impact on reducing or stopping the progress of cognitive decline, something for which there is no effective treatment,” says lead researcher Professor Katherine Samaras, Head of the Clinical Obesity, Nutrition and Adipose Biology lab at Garvan and endocrinologist at St Vincent’s Hospital Sydney.  

Metformin is approved by the Therapeutic Goods Administration and is one of the most commonly prescribed medications globally. It has been used to safely and cheaply treat patients with type 2 diabetes for around 60 years, by reducing the amount of glucose released by the liver and helping cells to better respond to blood-glucose levels.  

In a large six-year study, Professor Samaras and team previously found that people with type 2 diabetes taking metformin showed much slower cognitive decline and had reduced rates of dementia development, compared to those not taking the drug. 

“It’s thought that metformin assists the body in regulating the actions of insulin, thereby helping the brain to function better,” says Professor Samaras. “We want to find out if these effects are seen in people with normal glucose metabolism.” 

“As we survive physically for longer, to enjoy the benefits of longer independent lives, we need make sure we have good brain health,” she says. 

Success of the randomised-controlled trial, known as MetMemory, would mean that treatment for slowing cognitive decline could be immediately available.  

Previous research has indicated that metformin also has health benefits for cancer, heart disease, polycystic ovary syndrome and weight management. 

The clinical trial is already underway and requires more volunteers. Participants need to be aged over 60, live in the Greater Sydney region and be experiencing symptoms of mild cognitive impairment like challenges with memory loss and thinking.