Alteplase, a widely used drug to prevent the damaging disabilities of stroke and heart attacks, is effective even upto 4.5 hours after of the occurrence of the disease against the conventional 3 hours or so the drug was considered for use, endorse Indian physicians.
Alteplase is effective even if it is administered within 4.5 hours of onset of ischaemic stroke, said The Indian Stroke Association.
Alteplase is an injectable drug, given directly into a vein.
Alteplase is an enzyme that occurs naturally in man and causes blood clots to dissolve. It is a man-made protein manufactured by recombinant DNA technology. The naturally occurring protein, known as tissue plasminogen activator (TPA), is made by ovarian cells from the Chinese hamster.
Alteplase is used to treat conditions caused by arterial blood clots including heart attacks, strokes, chest pain at rest (unstable angina), blood clots in the lungs (pulmonary thrombosis), and other less common conditions involving blood clots.
The amount of Alteplace that is given to patients is far greater than the amount naturally made by the body itself.
Alteplase was first approved for heart attacks in 1987. In 1996, it was approved for strokes.
Intravenous (IV) administration of A is the only approved treatment for acute ischemic stroke.
It was earlier believed that Alteplase would be effective only even if it was administered within 3 hours of the onset of ischaemic stroke in a patient, a release said.
However, alteplase’ efficacy and safety when administered more than 3 hours after the onset of symptoms have not been established.
Researchers have recently tested the efficacy and safety of alteplase administered between 3 and 4.5 hours after the onset of a stroke.
Intravenous Alteplase administered between 3 and 4.5 hours after the onset of symptoms significantly improved clinical outcomes in patients with acute ischemic stroke, researchers wrote recently in New England Journal of Medicine.
Alteplase was more frequently associated with symptomatic intracranial hemorrhage.
The European Stroke Organisation (ESO), the American Stroke Association and the Lancet based on the key results from the European Cooperative Acute Stroke Study (ECASS 3).
The ECASS 3 trial was set up to investigate whether Alteplase can also safely extend the benefit of treatment in the 3 to 4.5 hour time window. ECASS 3 included 821 patients in 15 European countries who were recruited by a team of investigators led by Professor Werner Hacke of the University of Heidelberg. Results were published in the New England Journal of Medicine in September 2008.
ECASS 3, a randomised, double-blind, placebo-controlled trial, showed for the first time that thrombolysis with Alteplase can increase the likelihood of achieving good outcome with only minimal or no disability after an acute ischaemic stroke when administered in an extended time-window from 3 to 4.5 hours after symptom onset. This news comes shortly after The Lancet selected ECASS 3 as one of the top three papers of 2008, and Lancet editors singled out the study as their choice for paper of the year.
This time-window of an additional 1.5 hours is like a miracle of hope and life for a stroke victim for whom every ticking second is precious, experts said.
There are 16,67,372 stroke attacks in India every year and 4568 stroke attacks everyday. Of this, 800-1000 people die of stroke everyday whereas 1000-1500 people get paralysed for life after they suffer from stroke, as per WHO’s Workshop Report on Stroke Surveillance in India by the Division of Non-Communicable Diseases by the government and the Indian Council of Medical Research.
Around 5.7 million people in the world die each year from stroke, according to the World Health Organization estimates. Among survivors, 40 per cent experience moderate to severe disability and 10 per cent require institutional care.
For patients with an acute ischaemic stroke the only treatment currently available is Alteplase, which has to be administered within 3 hours of symptom onset according to its currently approved label.