New hope for stroke sufferers
Melbourne doctors are testing whether a new clot-busting drug can dramatically extend the time window patients can be treated for the most severe and common type of stroke.
Country patients and those who have a stroke in their sleep have the most to benefit from the $2.7 million international trial testing if the current 4.5 hours treatment window can be pushed out to 24 hours.
About 15,000 Australians suffer a stroke caused by a large blockage in a brain artery.
The first-line treatment for the past 20 years has been to give a clot busting medication called TPA - or Alteplase - within 4.5 hours of the stroke occurring, to help restore blood flow.
Following this, surgery at select hospitals to remove the clot is an option for some patients.
This strict time limit can leave those who live far away from hospital or "wake up stroke" patients, who don't know what time the episode occurred, ineligible for treatment.
The Royal Melbourne Hospital is now testing whether the time clock can be abandoned, and brain scans instead - which measure how much healthy brain tissue remains to be salvaged - can better predict who can still benefit from treatment up to a day after having a stroke.
RMH's director of neurology Professor Mark Parsons said after their previous trial found a new generation thrombolytic called Tenecteplase dissolved clots far quicker than standard TPA when given within 4.5 hours, they would now test this in the late time window.
Double the number of patients on Tenecteplase avoided needing surgery, as the clot dissolved before they reached hospital.
"A more effective clot busting drug will mean lots of patients might not need clot retrieval surgery," Prof Parsons said.
"The beauty of this study is that you don't need to know the exact stroke onset time, as long as the patient was seen well within 24 hours."
With just one in five patients having clot retrieval surgery, Prof Parsons said he hoped the trial could increase treatment access so more patients walked out of hospital following stroke.
The phase III study, funded by the National Health and Medical Research Council, will start recruiting patients from Australia and seven other countries early next year.
Newcastle neurologist Dr Timothy Ang, from the Stroke Foundation Clinical Council, said while expanding the treatment time window would be a breakthrough, with millions of brain cells dying every minute after stroke, timely treatment remained vital.
"We may find some people who are eligible for treatment later, but some people have very little salvageable brain after three or four hours," Dr Ang said.
"We don't want anyone waiting at home after a stroke."