FibroGen's FG-4539 reduces brain tissue damage in ischemic stroke

Florida, USA-based FibroGen has said that a single dose of FG-4539, its novel small-molecule inhibitor of hypoxia-inducible factor (HIF) prolyl hydroxylase (PH) in development for the treatment of ischemic disease, was neuroprotective and significantly reduced brain tissue damage in a preclinical model of permanent ischemic stroke. The potency of FG-4539 and the window of therapeutic opportunity observed following permanent middle cerebral artery occlusion (pMCAO) compare favorably to results from this model reported for the most promising neuroprotective therapies currently in development. The data were presented on February 17 at the International Stroke Conference 2006 (Abstract number 427).

Around 15 million people worldwide suffer a stroke each year, resulting in death or cognitive deficits. The majority of these are ischemic strokes caused by a blood clot that prevents blood flow to the brain, thereby depriving the brain of oxygen and nutrients. As a result, numerous pathological pathways are triggered and lead to the propagation of neuronal cell death from the initial site of ischemic damage.

The US Food and Drug Administration has approved tissue plasminogen activator, or tPA, (ie, Alteplase) to treat ischemic stroke. tPA is a thrombolytic drug that helps to restore blood flow to the brain by dissolving the blood clot that causes ischemic stroke. In practice, however, the treatment window for administration of tPA is limited to three hours after onset of stroke symptoms, and less than 5% of patients receive tPA. In addition, tPA does not address other pathological processes that cause neuronal cell death.