my personal edition > stroke > news


  E-Mail this DGDispatch to a colleague

DGDispatch

Tissue Plasminogen Activator Use In Stroke May Expand to Reduce Disability: Presented at ANA

By Maggie Schwarz

WASHINGTON, DC -- October 12, 2007 -- In the next few years, it may be possible to use tissue plasminogen activator (tPA) may be expanded beyond the 3-hour window during which patients with ischaemic stroke can be treated to reduce the risk of disability, according to a proteomic study presented here at the 132nd Annual Meeting of the American Neurological Association (ANA).

MingMing Ning, MD, Director, Clinical Proteomics Research Center, Department of Neurology, Massachusetts General Hospital and Instructor, Neurology, Harvard University, Boston, Massachusetts, United States, conducted the study to determine whether tPA can be given outside of the 3-hour therapeutic window.

"tPA is the only [U.S.] Food & Drug Administration-approved medical therapy for acute ischaemic stroke, and is given to less than 5% of stroke patients because it raises the risk of intracranial hemorrhage tenfold. The 3-hour time window in which tPA must be given vastly limits its use," lamented Dr. Ning.

"If we could find biomarkers of haemorrhage -- the risk of which rises after 3 hours of stroke symptom onset -- we could expand the use of tPA," explained Dr. Ning, "and reduce disability from stroke. We want to be able to give tPA to many more people but not cause bleeds."

Using proteomic analysis, the researchers looked at the blood profile of 50 stroke patients after they received tPA within 3 hours of first experiencing stroke symptoms. "We wanted to get a fingerprint of those [who were] more likely to do well and less likely to bleed," said Dr. Ning.

The researchers found that matrix metalloproteinases (MMPs) were upregulated by tPA. "High levels of certain MMPs correlated with haemorrhage" said Dr. Ning.
"A low level of these MMPs constituted a good fingerprint, with less likelihood of a bleed."

By generating a proteomically-derived fingerprint of ischaemic stroke patients who are less likely to bleed, Dr. Ning hopes that ultimately, more patients will be eligible to receive tPA outside of the current 3-hour window. A greater number of patients will survive ischaemic stroke with less disability, or without disability.

The investigators are planning a larger study to validate the fingerprint. "These biomarkers can help triage tPA treatment and widen the time window in which to give tPA. Giving tPA to more patients may save them from the disability of stroke," Dr. Ning concluded.


[Presentation title: Pharmaco-proteomics at the Bedside: A Study of tPA Treatment in Acute Ischemic Stroke Patients.]

E-Mail this DGDispatch to a colleague

To print, use this version