A "GAME-CHANGING" Alzheimer's drug that slows mental decline by up to 60 per cent has been approved in the United States. Donanemab , sold in the US under the brand name Kisunla, will be available for patients with early symptoms of the disease. The medicine remains under consideration by Britain's regulator, the Medicines and Healthcare products Regulatory Agency (MHRA).

A decision is expected in the coming months. Samantha Benham-Hermetz, executive director of policy and communications at Alzheimer’s Research UK, said: "Today’s decision by the regulators in the US marks another important milestone in the global effort to tackle dementia. "We are hopeful that a decision will be made later this year for Great Britain.

" Donanemab , made by pharmaceutical company Eli Lilly, is an antibody-based treatment designed to remove amyloid - one of the hallmark proteins that builds up in the brains of people with Alzheimer’s. It is given as an infusion into a person’s arm once a month. Clinical trials have found it cleared toxic proteins out of patients’ brains and slowed mental decline by up to 60 per cent over 18 months.

It was most effective for people in the earliest stages of Alzheimer’s – the top cause of dementia – and slowed decline by 36 per cent on average. Among all participants, treatment with donanemab reduced amyloid plaque on average by 84 per cent at 18 months, compared with a one per cent decrease for participants taking a placebo. The Food and Drug Admi.