Dr. John Hallenbeck and his colleagues at the National Institute of Neurological Disorders and Stroke (NINDS) in Bethesda, Maryland demonstrated that nasal administration of recombinant human E-selectin protein inhibited the development of ischemic and hemorrhagic strokes in spontaneously hypertensive, genetically-stroke-prone rats by induction of mucosal tolerance.

These results suggested that E-selectin tolerization, with further testing and development, may be a new treatment modality for human stroke. A collaborative team forged December 19, 2001 between NINDS and Novavax Inc in a Cooperative Research and Development Agreement (CRADA) has been developing E-selectin-based biological products for prevention and treatment of strokes.

Stroke is the third leading cause of death in the United States and the major cause of disability. Despite the success of recent clinical trials with antithrombotic drugs for the treatment of acute stroke and for the prevention of recurrent stroke, recurrent strokes occur annually in approximately 10% of stroke patients suffering a recent cerebrovascular attack. Unlike new drugs that may inhibit the activity of cell adhesion molecules like E-selectin, the tolerization method using the E-selectin protein permits immune suppression of the harmful proinflammatory responses associated with stroke without the toxicity problems found with inhibitory drugs.

Dr. Robin Robinson, Director of Vaccine Technologies and Principal Investigator of the E-selectin project for Novavax, Inc. stated, "The Hallenbeck studies provide further support for E-selectin induced tolerance as a viable means to prevent stroke and/or reduce collateral damage during a stroke attack. That E-selectin is a key target in the proinflammatory response associated with stroke is corroborated by these findings. These results provide supportive evidence that E-selectin tolerization may someday be useful in the prevention of primary strokes and treatment of secondary strokes. Novavax and the NINDS are moving forward together in the development of these recombinant E-selectin proteins as tolerogens."