A genetic study has been launched following hundreds of reported pancreatitis cases linked to weight loss and diabetes jabs, including ten deaths.
Researchers will examine whether genetic differences influence the risk of developing pancreatitis — inflammation of the pancreas — in people taking GLP-1 medicines.
These drugs mimic a natural hormone that helps regulate blood sugar and appetite, making individuals feel fuller.
Although not confirmed as directly caused by the medicines, hundreds of cases of acute and chronic pancreatitis have been reported to the Medicines and Healthcare products Regulatory Agency (MHRA) since the treatments were licensed.
The MHRA and Genomics England are now launching the Yellow Card Biobank project to investigate whether some people may have a genetic predisposition to this reaction.
Dr Alison Cave, MHRA chief safety officer, said: “Evidence shows that almost a third of side effects to medicines could be prevented with the introduction of genetic testing.
“It is predicted that adverse drug reactions could cost the NHS more than £2.2bn a year in hospital stays alone.
“Information from the Yellow Card Biobank will help us to better predict those most at risk of adverse reactions – enabling patients across the UK to receive the safest medicine for them, based on their genetic makeup.”
GLP-1 agonists can lower blood sugar levels in people with type 2 diabetes and may also be prescribed to support weight loss.
Current estimates suggest around 1.6m people in the UK are using weight loss jabs.
Most side effects are gastrointestinal, including nausea, constipation and diarrhoea.
The MHRA has also warned that Mounjaro may reduce the effectiveness of the oral contraceptive pill in some patients.
The death of 58-year-old nurse Susan McGowan from North Lanarkshire has brought further attention to possible risks.
She died on 4 September after taking two doses of Mounjaro over two weeks.
Her death certificate, seen by the BBC, listed multiple organ failure, septic shock and pancreatitis as immediate causes of death, with “the use of prescribed tirzepatide” noted as a contributing factor.
She had obtained a prescription via an online pharmacy after seeking medical advice.
Professor Matt Brown, chief scientific officer at Genomics England, said: “GLP-1 medicines like Ozempic and Wegovy have been making headlines, but like all medicines there can be a risk of serious side effects.
“We believe there is real potential to minimise these with many adverse reactions having a genetic cause.
“This next step in our partnership with the MHRA will generate data and evidence for safer and more effective treatment through more personalised approaches to prescription, supporting a shift towards an increasingly prevention-focused healthcare system.”
The study aims to identify genetic markers that could help predict which patients are more likely to develop pancreatitis, potentially allowing for safer, more personalised prescribing of these widely used treatments.