Knoll's Ancrod Enters Pivotal Trial For Stroke

Knoll's ancrod, an anticoagulant derived from Malayan pit viper venom, is to enter a further Phase III trial in the USA to see if the fibrinogen-lowerer can limit the neurological disability following an acute ischemic stroke. 25 US medical facilities will participate in the two-year study.

As in the NINDS study of Genentech's Activase (alteplase; see story above), study design calls for patients to present and be diagnosed with an ischemic stroke within three hours of symptom onset.

Ancrod is being evaluated because it may clear thrombi in the brain more slowly than other thrombolytics. The rationale is that a more gradual dissolution of clots may reduce the risk of intracranial hemorrhage. Victor Erlich, a neurologist at Northwest Hospital in Seattle, noted that the vasculature in the brain is not as robust as that in the heart, so it is more prone to rupture after the sudden break-up of a clot.