UK patients aged five and up who have severe sickle cell disease or transfusion-dependent β-thalassaemia are now able to receive a gene-editing treatment, the MHRA has announced. Casgevy (exagamglogene autotemcel), until now authorised only for those aged 12 and above, has had its approved use widened by the regulator.
Key points
- Who is covered — children aged five and over who meet the eligibility criteria.
- The conditions — both are inherited faults in the haemoglobin genes; β-thalassaemia patients often need transfusions every three to five weeks.
- How it works — a faulty gene in bone marrow stem cells is edited in a laboratory, and the cells are then infused back into the patient.
- Side effects — nausea, fatigue, fever and a higher risk of infection.
Neither condition goes away, and either can prove fatal. The genetic error behind severe sickle cell disease may bring on anaemia, dangerous infections that threaten life, and episodes of intense pain. β-thalassaemia causes serious anaemia, and those affected frequently depend on medicines and blood transfusions given on a regular basis for their whole lives.
Casgevy corrects the defective gene in stem cells taken from the patient's bone marrow, allowing the body to make haemoglobin that works. The cells are gathered, edited in a lab, and returned by infusion following conditioning treatment; while the treated cells take hold in the marrow, a hospital stay may be required.
Julian Beach, MHRA Executive Director Operations, said the decision rested on a thorough review of the data on how safe, effective and good-quality the treatment is. Monitoring of its performance will continue, he added. Vertex Pharmaceuticals (Europe) Ltd received the extension on 29 October 2026. Roughly 15,000 people in the UK are living with sickle cell disorder.
What it means in practice
For families of young children with these conditions, the change opens a treatment option that was previously out of reach until the teenage years. It does not mean every eligible child will be treated: clinicians will still decide who is suitable, and the process involves collecting stem cells, a stay in hospital and a recovery period.
- Ask about eligibility — parents of children aged five and over with either condition can raise the option at their next specialist appointment.
- Plan for time away — treatment and recovery may mean hospital stays, so schooling and work cover will need sorting.
- Watch for side effects — fever, fatigue and infection risk mean families should know who to contact if symptoms appear.
