The defect that causes the neurodegenerative disease Huntington’s has been corrected in patients for the first time, the BBC has learned. An experimental drug, injected into spinal fluid, safely lowered levels of toxic proteins in the brain. The research team, at University College London, says there is now hope the deadly disease can be stopped. Experts say it could be the biggest breakthrough in neurodegenerative diseases for 50 years. Huntington’s is one of the most devastating diseases. Some patients described it as Parkinson’s, Alzheimer’s and motor neurone disease rolled into one. Peter Allen, 51, is in the early stages of Huntington’s and took part in the trial: “You end up in almost a vegetative state, it’s a horrible end.” Huntington’s blights families. Peter has seen his mum Stephanie, uncle Keith and grandmother Olive die from it. Tests show his sister Sandy and brother Frank will develop the disease. The three siblings have eight children – all young adults, each of whom has a 50-50 chance of developing the disease.