Genetic test should be new standard of care in UK for stroke patients

People who have had the most common type of stroke should have a genetic test to find out whether they can be treated with a drug to help reduce the risk of further brain attacks, the UK’s NHS watchdog has said.

New draft guidelines published on May 19 by the National Institute for Health and Care Excellence (NICE) recommend that people who have suffered an ischaemic stroke – where a clot blocks the flow of blood and oxygen to the brain – or a transient ischaemic attack (TIA) should be offered laboratory-based genotype testing if treatment with the drug clopidogrel is being considered by clinicians.

NICE currently recommends clopidogrel can be used as an option for treating people at risk of a secondary stroke but this treatment is not suitable for those with certain variations in a gene called CYP2C19 because they cannot convert the drug to the active form.

The genotype test would be used to find out who has these variants so they can be treated with an alternative drug = potentially saving thousands of lives.

If laboratory testing – estimated to cost around £139 per analysis – is not possible, NICE has said the Genomadix Cube point-of-care check at a cost of £197, which can be given at the bedside, can be used instead.

There are around 100,000 strokes every year in the UK, of which approximately43,000 are recurrent. Each year, 46,000 people in the UK have a TIA for the first time – a warning that they are at risk of stroke.

A stroke can occur in anyone of any age. but the chance of having one about doubles every 10 years after reaching 55. The majority of strokes occur in people who are 65 or older.

Clopidogrel – which also goes under the brand names Grepid and Plavix – is the standard anti-clotting medication given to patients.

But at present no testing takes place to find out who is suitable for treatment with the drug.

An estimated 32% of people in the UK have at least one of the highlighted CYP2C19 gene variants. They are more commonly found in people with an Asian family background but can be present in those of any ethnicity.

Evidence has suggested that people with these variants have around a 46% increased risk of another stroke when taking clopidogrel compared to those without them.

If the test discovers they have one of the CYP2C19 gene variants, the person will be treated with another medicine, which will be more effective at preventing future blood clots.

Around 11 million items of clopidogrel are dispensed each year at a cost of around £16 million to the NHS.

Mark Chapman, interim director of medical technology and digital evaluation, at NICE, said: “The recommendation is a step forward in ensuring people who have had a stroke receive personalised care thanks to a genetic test run after their DNA is sequenced using their blood or saliva.

“Treatment with clopidogrel is effective in preventing further strokes for the majority of people who don’t have the gene variant. But until now doctors have not known who cannot be treated with clopidogrel until after they’ve had a second stroke or TIA and that could be too late.

“If the CYP2C19 variants are found, other treatment options can be used. This test ensures we’re getting the best care to people quickly, while at the same time ensuring value for money for the taxpayer.”

A consultation has begun on the draft recommendations and consultees can have their say via nice.org.uk until Wednesday June 8, 2023.

Juliet Bouverie, Chief Executive of the UK-based Stroke Association, has welcomed the NICE announcement. She said: “Stroke devastates lives and leaves people with life-long disability. We know that many stroke survivors spend the rest of their lives fearing another stroke, so it’s great to see that more people could be given appropriate help to significantly cut their risk of recurrent stroke.

“Anything we can do to prevent the misery that stroke can cause is ultimately good news. Getting on the right medication and taking it as advised can really go far to prevent further strokes.”

A team at NHS Tayside in Scotland led by stroke specialist Dr Alex Doney at Ninewells Hospital in Dundee, has already been pioneering routine gene testing for clopidogrelin in brain attack patients. It has been estimated the test, developed by East of Scotland Regional Genetic Laboratory, will lead to improved outcomes for about 400 patients with heart disease and 600 stroke patients each year.

One of the first patients in Tayside to be managed on the new stroke pathway has been 67-year-old Ian Anderson from Perth. He has previously said: “I felt privileged to be one of the first patients in Tayside to be involved in this new approach. It really is a step into the future and one that will benefit patients in the coming months and years.

“It is quite amazing that a simple blood test can show if my medication is working as effectively as possible and it is reassuring that my medication can be tailored more precisely to me.”

Clinicians believe this is just the tip of the iceberg and other conditions could soon benefit from the same precision prescribing, making routinely given medicines safer and more effective for individual patients.