Battle of the clot-busters in international stroke trial

Dec 3 2013

Professor Mark Parsons and his former patient Sylvia Ryan.

Professor Mark Parsons and his former patient Sylvia Ryan.

An HMRI stroke drug trial that yielded rapid treatment benefits for patients is being expanded nationally and internationally from today, with new funding support from the National Heart Foundation of Australia.

Led by neurologist Professor Mark Parsons, researchers from the University of Newcastle and Hunter New England Health are establishing a network of 20 acute stroke centres around Australia and 50 world-wide, with the clinical trial to cost an estimated $5 million overall.

They will be investigating the effectiveness of the clot-busting drug Tenecteplase, commonly used for heart attacks, over the standard stroke treatment Alteplase in a broader group of stroke victims. The study has been dubbed TASTE (Tenecteplase versus Alteplase for Stroke Thrombolysis Evaluation).

Results from the Phase II trial conducted between 2008-2011 found two-thirds of patients treated with Tenecteplase showed major neurological improvement within a day, compared with 36 per cent for those administered Alteplase.

“Using Tenecteplase we’ve seen patients severely affected by stroke returning to normal function within two or three days,” Professor Parsons said. “The future is looking very promising but we now need this larger study to see if this drug benefits stroke patients in the real world.

“The Heart Foundation is supporting the study with a Future Leaders Fellowship, which allows us to bring imaging specialist Dr Andrew Bivard back to the Hunter after working in Melbourne.”

Heart Foundation NSW Chief Executive, Ms Kerry Doyle, commented: “In NSW we have some of the most innovative and outstanding researchers who are tackling the multiple facets of cardiovascular disease and stroke head-on.

“It is vital that we build our research in these areas which claim more lives than any other disease in Australia, to better understand and discover new techniques and models of clinical care which directly impact on the lives of individuals.”

With advanced MRI and CT perfusion imaging being required to identify suitable trial candidates, Professor Parsons has been travelling extensively in recent months surveying hospital centres and checking their scanning infrastructure and capabilities.

“We use a rigorous criterion to find patients mostly likely to benefit from clot-busting treatment,” Professor Parsons said.

“With our initial study we screened 2,800 patients before enrolling 75, whereas for the new trial we need to enrol 1,000 patients, which will average at around five patients per site per year.”

Stroke program leader Professor Chris Levi said the trial would utilise new software technology developed by collaborators in the US.

“The participating centres are installing a system for automated scan analysis, which processes the CT image into an automatic readout telling the doctor how much salvageable brain tissue there is,” Professor Levi said.

“They can then make a decision on whether to randomise the patient for the trial because there is no point administering a clot-busting drug unless there’s a substantial amount of brain tissue left to save.

“That said, even the standard drug Alteplase is under-utilised, with some hospitals only treating 5 per cent of patients where they could be treating 20 per cent.”

Stroke survivor Sylvia Ryan, from Pokolbin, was given Tenecteplase under the Phase II trial after arriving at John Hunter Hospital partially paralysed and unable to speak.

The following day, as part of regular cognitive tests, nursing staff asked Mrs Ryan if she knew where she was. She heard herself saying “John Hunter Hospital”.

“Suddenly I was screaming out, ‘I can speak, I can speak’ … I think the whole hospital heard me,” Mrs Ryan said. She left hospital days later, walking and talking, and has required no further speech pathology or physiotherapy.

Professor Mark Parsons is a Staff Specialist in Neurology at John Hunter Hospital. Professor Chris Levi is Director of the Acute Stroke Services at John Hunter Hospital and Director of the Priority Research Centre for Translational Neuroscience and Mental Health at the University of Newcastle. HMRI is a partnership between the University of Newcastle, Hunter New England Health and the community.