Immediate Neurological Recovery Following Perispinal Etanercept Years After Brain Injury

Positron emission tomographic brain imaging and pathological examination have revealed that a chronic, intracerebral neuroinflammatory response lasting for years after a single brain injury may occur in humans. Evidence suggests the immune signaling molecule, tumor necrosis factor (TNF), is centrally involved in this pathology through its modulation of microglial activation, role in synaptic dysfunction, and induction of depressive symptoms and neuropathic pain. Etanercept is a recombinant TNF receptor fusion protein and potent TNF inhibitor that has been found to reduce microglial activation and neuropathic pain in multiple experimental models. We report that a single dose of perispinal etanercept produced an immediate, profound, and sustained improvement in expressive aphasia, speech apraxia, and left hemiparesis in a patient with chronic, intractable, debilitating neurological dysfunction present for more than 3 years after acute brain injury. These results indicate that acute brain injury-induced pathologic levels of TNF may provide a therapeutic target that can be addressed years after injury. Perispinal administration of etanercept is capable of producing immediate relief from brain injury-mediated neurological dysfunction.