Tuesday, September 2, 2014
Acute treatments after 3 hours
Are there any acute treatments for stroke that can be given after the 3 hour window?
Only one clinical trial has shown benefit for stroke treatment after 3 hours. This was called the PROACT II trial. The full title and reference are below. (Intra-arterial prourokinase for acute ischemic stroke. The PROACT II study: a randomized controlled trial. Prolyse in Acute Cerebral Thromboembolism.; JAMA. 1999 Dec 1;282(21):2003-11.) In PROACT II, patients who came to the hospital for medical attention up to 6 hours after stroke onset could be treated using a drug called prourokinase. This is a clot-busting drug similar to tPA, which is the FDA approved and widely used clot busting drug for the 0-3 hour time window. The prourokinase was given by catheter, which is a long tube that can be used in the blood vessels to give the drug right at the clot site in the brain. PROACT II showed benefit for this treatment as compared to placebo. Unfortunately, the medication did not receive FDA approval and thus is not currently available. Some centers do offer this same type of catheter-based therapy to patients up to 6 hours after stroke, but use tPA instead of prourokinase. Since the treatment is not FDA approved, it would likely be offered only for severe strokes where the outcome is predicted to be very poor if some treatment is not administered. There is a good deal of research that is ongoing in an attempt to develop therapies that can be offered at later times after stroke onset. Unfortunately, most of these therapies are at least several years of testing away from being FDA approved and offered outside of clinical research studies.
Brett Kissela, MD
Assistant Professor of Neurology
Director, Neurology Residency Program
College of Medicine
University of Cincinnati