The pilot study, conducted by doctors at Imperial College Healthcare NHS Trust and scientists at Imperial College London, saw five stroke victims injected with stem cells directly into their damaged brain within seven days of a stroke.
The stem cells were taken from the patients’ own bone marrow.
The scientists said it showed “promising results”, with all the patients showing improvements in disability within six months – something that had only previously been shown in animals.
Four out of five patients had the most severe type of stroke, which only four per cent of people are expected to survive and lead independent lives after six months.
In the trial, all four were alive and three were independent after six months.
Professor Nagy Habib, from the department of surgery and cancer at Imperial College London, said: “These are early but exciting data worth pursuing.
“Scientific evidence from our lab further supports the clinical findings and our aim is to develop a drug, based on the factors secreted by stem cells, that could be stored in the hospital pharmacy so that it is administered to the patient immediately following the diagnosis of stroke in the emergency room.