A discarded diabetes drug could be the key to beating organ transplant rejection, a landmark study has found.
One in six heart recipients die within a year, and those that do survive face higher risk of infection, weight gain, cancer and diabetes from their life-long regime of immunosuppressant drugs.
However, a new study by Queen Mary University of London found that by repurposing a drug designed to treat diabetes, they could speed up the process necessary for the blood system to fuse into the new organ.
The researchers say this finding could be a game-changer – and a cost-effective one at that, since the drug already exists and has proved in other trials to be safe in humans.
Researchers at Queen Mary University of London successfully repurposed a diabetes drug to prevent rejection without the side effects of current immunosuppressive drugs (file image)
The drug is designed to increase the activity of an enzyme called glucokinase, which is suppressed in people with type 2 diabetes.
For diabetes patients, this enzyme is essential for regulating blood sugar levels.
For those who undergo a transplant, the enzyme is essential to drive the movement of a certain T cell (known as a ‘regulatory T cell’) into human organs.
Inside the organ, the T cells build up the immune system, helping it to fuse with the new body, and preventing rejection.
The drug had been sidelined for further development for diabetes patients, but a team at Queen Mary University decided to test its effects on transplant patients.
Testing the drug on mice, they found that it dramatically increased the flow of regulatory T cells into the new organs.
The team then studied blood samples from a group of people who have a genetic mutation making their version of the glucokinase enzyme more active.
They found that in these people, the regulatory T cells move into the organs more readily.
Lead author Professor Federica Marelli-Berg, Professor of Cardiovascular Immunology at Queen Mary’s, said the discovery can be classed as a breakthrough.
‘With this research we’ve hit upon a completely different way to stop organ rejection,’ she said.
‘Our next step is to take the drug into clinical trials. If the trials are successful, these findings could prove to be life-changing for patients who have had a transplant.’
Currently, drugs used to prevent organ rejection have a number of side effects, including a greater risk of infections and cancer.
This is largely down to the fact that they are unable to specifically target the area of the immune system responsible for organ rejection.
Professor Jeremy Pearson, Associate Medical Director at the British Heart Foundation, which funded the research, said the findings are some of the most promising to date.
‘Heart transplantation has come a long way since the first heart transplant nearly fifty years ago. However, when our immune system rejects the donated heart this can have devastating consequences,’ he said.
‘With this research we are one step closer to reducing the number of people suffering from organ rejection, and to prevent people from re-joining a growing transplant waiting list.
‘Ultimately, allowing people who have undergone this procedure to live longer, healthier lives with a healthy donor heart.’