Bangalore: The blood cancer drug Glivec could turn out to be a saviour for stroke patients, many of whom cannot take tissue plasminogen activator, or tPA, the most effective clot-busting drug, due to a narrow safety window, researchers report in Monday’s issue of journal ‘Nature Medicine’.
A stroke occurs when brain cells die because of inadequate blood flow to the brain.
According to the World Health Organization, 80% of the 15 million strokes that occur each year are caused by a type of blood clots in the brain that tPA can dissolve. But the drug is safe only if given within the first three hours following the onset of symptoms, after which it may cause dangerous bleeding in the brain. Less than 3% of patients with this type of stroke receive tPA because by the time they reach hospital and get diagnosed, the narrow safety window has closed.
Working on mice, researchers from the Stockholm branch of the Ludwig Institute for Cancer Research and the University of Michigan Medical School showed that when tPA was given with Glivec, or imatinib, the risk of bleeding was greatly reduced, even after being given as late as five hours after the stroke. A human study on stroke patients is being undertaken at Karolinska Univserity Hospital in Stockholm.
Swiss drug maker Novartis AG, which holds the patent on Glivec, challenged the Indian patent office’s rejection of its patent in 2006, but the court rejected the case in April 2007. Six Indian companies, including Cipla Ltd, Natco Pharmaceutical Ltd and Ranbaxy Laboratories Ltd make generic versions of Glivec.