MHRA extends Casgevy licence to children aged five and over

The therapy, whose generic name is exagamglogene autotemcel, was previously authorised in the UK only for patients aged 12 and above. The extension lowers the age floor to five for children with severe sickle cell disease or transfusion-dependent beta thalassemia.

Julian Beach, the MHRA's executive director of operations, said the conditions are serious, lifelong and in some cases fatal. 'This approval means this innovative gene-editing treatment can now be used in eligible children from the age of five, extending this treatment option to younger patients,' he said.

The MHRA said the decision followed an assessment of the treatment's safety, quality and effectiveness.

Why the age limit mattered

The MHRA was the first regulator in the world to approve Casgevy. It cleared the therapy for adults and older adolescents in late 2023. The BBC reported at the time that it was the first licensed medicine built on CRISPR, the gene-editing tool whose discoverers won the Nobel prize in 2020.

In trials cited then, 28 of 29 sickle cell patients were free of severe pain. Among beta thalassemia patients, 39 of 42 no longer needed transfusions for at least a year. Around 15,000 people in the UK have sickle cell disease, and almost 300 babies are born with it each year, the BBC reported. More than 1,000 people in the UK are affected by thalassemia.

What the treatment involves

Open Access Government reported that Casgevy, developed by Vertex with CRISPR Therapeutics, is the first approved therapy to use CRISPR/Cas9 gene editing. Stem cells are collected from the patient's bone marrow, edited in a laboratory and returned by infusion. Patients first undergo conditioning treatment to prepare the bone marrow, and they may need to stay in hospital afterwards while the edited cells settle and start working. Side effects include nausea, fatigue, fever and an increased risk of infection.

The BBC reported on Vian, a 16-year-old from Coventry whose edited cells were returned last December. She no longer needs the monthly transfusions she had most of her life. Sarah Lawson, a consultant haematologist, described the treatment as a 'functional cure': the disease does not go away, but the problems it caused are removed.

Cost and access

When the MHRA first approved Casgevy, no price had been set and the BBC reported the one-off treatment was likely to cost £1 million or more. It said the health assessment body NICE would determine whether the therapy is cost-effective.

The regulator said it will continue monitoring Casgevy as use widens. The treatment will be available to children who meet eligibility criteria.