Doctors say a stem cell transplant could be a "game changer" for many patients with multiple sclerosis.
Results from an international trial show that it was able to stop the disease and improve symptoms.
It involves wiping out a patient's immune system using cancer drugs and then rebooting it with a stem cell transplant.
Louise Willetts, 36, from Rotherham, is now symptom-free and told me: "It feels like a miracle."