For the 800,000 people in the United States who suffer a stroke each year, the window for drug therapy closes in the first few hours after the attack. That leaves some seven million stroke survivors in this country alone with no medical alternative beyond physical therapy. A small pharmaceutical company in New York hopes to change that with a drug that may help patients regain some of their lost mobility six months or more after a stroke.Acorda is also developing drugs to treat Multiple Sclerosis and spinal cord injuries:
Strokes happen when blood stops flowing to part of the brain, often due to a blood clot. Without blood to bring new oxygen, cells in the affected region start to die. If the symptoms of stroke are recognized quickly enough and the victim is brought to a hospital within a few hours, doctors can administer a clot-dissolving drug to minimize the damage. But only a small fraction of stroke patients seek medical attention soon enough for this intervention.
In the future, stroke patients who miss this window and are affected by reduced mobility long after their stroke may be able to turn to a drug that helps damaged nerves transmit electrical signals in the brain.
Earlier this year, Acorda Therapeutics reported that the compound dalfampridine improved motor function in both the forelimbs and hind limbs of rats that had suffered a stroke. This month, the company began recruiting patients for a clinical trial to test the effects of the compound in human stroke patients. Acorda plans to enroll about 70 people who have had a stroke at least six months prior. "That's the time that deficits seem to stabilize, so we can eliminate naturally occurring improvements in patients," says Jeff MacDonald, an Acorda spokesman.
Spinal-cord injuries still garner a lot of focus from the company, which hopes to begin testing a compound licensed from Medtronic that protects neurons from the wave of cell death that follows the initial injury. Medtronic had already shown the compound to be safe in healthy patients, and later this year, Acorda plans to test its efficacy in patients in the first hours after a spinal-cord injury.We should be thankful that there are companies like Acorda out there, but we need also be mindful that Acorda stays in business only to the extent that it can make a profit. Government regulations and high taxation will make it much harder for these companies to keep doing research and may thus ensure the continued disability or deaths of a lot of people who might in the future have benefited from the work they do.
Patients with injured spinal cords are not nearly as numerous as stroke patients, "but if you are talking about costs to society, spinal-cord injuries are extremely expensive," says Naomi Kleitman, a spinal-cord injury expert with NINDS. "They tend to happen in fairly young people who need a lot of medical and assistive help if they have severe injuries."
The company is also looking to treat longer-standing spinal-cord injuries with a drug that would help break down the scar tissue that forms around a spinal-cord injury. The scar tissue is thought to prevent nerves from establishing the new connections that may help patients recover some functionality. The product is still in early development, and one challenge will be devising a method to deliver the large scar-busting molecule to its target site.
Despite the pressing need, the small market for spinal-cord injury drugs may be one reason the condition doesn't get a lot of attention from pharmaceutical giants. "No one else wants to develop compounds to treat spinal-cord injury as seriously as Acorda," says Edward Hall, a neurologist and spinal-cord and brain-injury specialist at the University of Kentucky in Lexington. "These aren't going to be billion-dollar-a-year products."