Tests in human patients have already begun. Newer and more exciting results show that this and another growth factor, given days after a stroke, help animals regain functions that were lost to strokes. Trials with people are expected to begin within a year. Present in the brain and other parts of the body, they keep cells alive and promote their growth. Someone in the United States suffers a stroke every 53 seconds and someone dies from one every 3.3 minutes.
Most strokes result from clots blocking blood vessels in the brain.
Growth factors, also given within a few hours, work by reducing the number of brain cells killed by a lack of the oxygen carried in blood. The medicine was then tested in 46 patients and found to be safe for human use. Although 500,000 to 700,000 Americans suffer strokes each year, two out of every three survive. As time passes many of these people, including those with stroke-induced paralysis and loss of speech, experience partial recovery. They regain some use of speech and other cognitive functions, as well as more use of arms and legs that may have been partly or fully paralyzed.