Revolutionary gene therapy could cure thousands of haemophiliacs

Up to 2,000 Britons could be cured of haemophilia as a new treatment is given the green light by drug regulators.

Haemophilia – a condition that affects the blood’s ability to clot – is currently treated with regular injections, which replace the clotting ‘factor’ in the patient’s blood.

But a trial found a one-off infusion of a gene therapy called Hemgenix massively improved the blood clotting abilities of people with a type of the condition, known as haemophilia B.

What’s more, they have retained this ability years after receiving the treatment – indicating the effects could be permanent.

Last night, a leading blood doctor said the decision by the Medicines and Healthcare products Regulatory Agency (MHRA) to approve it for use marked a ‘revolution’ in haemophilia treatment.

Consultant haematologist Dr Rashid Kazmi, who led the Hemgenix trial in the UK, says that currently, even with injections, haemophiliacs are prone to ‘trauma-related bleeds’. 

These can be quite minor – as insignificant as a heavy knock or a joint sprain – but can lead to serious problems including chronic pain and, rarely, paralysis.

Dr Kazmi, of University Hospital Southampton, said: ‘We don’t yet know how long the effects of the new treatment will last – but for haemophilia B things are looking promising.’

Hemgenix works by smuggling a gene into blood cells, which enables them to produce the missing clotting factor. They do this by using a harmless virus as a Trojan horse to enter cells.

Some 54 haemophiliacs took part in the trial, and their number of bleeds dropped by two-thirds on average after the gene therapy treatment. 

Some 96 per cent also stopped having to have their usual injections. After two years of tracking, no reduction in clotting ability has been seen.

Whether it becomes available on the NHS is down to the National Institute of Health and Care Excellence (NICE). Its decision is likely to be made later this year.