Safety and Efficacy Study of Etanercept for Aneurysmal Subarachnoid Hemorrhage

Subarachnoid Hemorrhage, Aneurysmal Clinical Trial

Official title: Phase I Safety, Blood Brain Barrier Permeability and Potential Efficacy of Etanercept for Aneurysmal Subarachnoid Hemorrhage

Status Withdrawn

Clinical Trial Summary

Subarachnoid hemorrhage (SAH) is a special type of stroke that typically results from a ruptured intracranial aneurysm, a weakening in the wall of a blood vessel. This type of life-threatening bleeding occurs in over 3000 Canadians per year, usually in working age adults. Although this type of stroke accounts for only 5-10% of strokes, it contributes a disproportionately larger percent of overall stroke morbidity and mortality due in part to the young age of those affected. If one is fortunate enough to survive the initial bleeding episode and the subsequent surgical treatment of the aneurysm, a patient may still develop secondary strokes 3 to 14 days after the initial bleed. These delayed strokes are the most significant cause of morbidity and mortality after SAH and may be potentially preventable. Currently, there is only one medication (an anti-hypertensive) that has convincingly shown to improve outcomes after SAH. The molecular pathway causing these delayed strokes is still not clear, and this is an active area of research.

Animal studies have revealed that these delayed strokes may be caused by a pro-inflammation molecule called tumor necrosis factor alpha (TNFa). Delayed strokes were prevented experimentally by a TNFa blocker called etanercept. This clinical study, utilizing prophylactic treatment with etanercept in patients with SAH, will ensure the safety of this drug and determine its effectiveness in preventing delayed strokes.

Clinical Trial Description

SAH from a ruptured cerebral aneurysm has an incidence of 10 per 100,000 Canadians (over 3000 people annually). If a person survives SAH from a ruptured intracranial aneurysm, the most common complication is delayed cerebral ischemia (DCI). This is the delayed neurologic deterioration associated with angiographic vasospasm. Vasospasm refers to the arterial constriction that typically begins 3 days after SAH, is maximal 7 to 8 days later and generally resolves by 14 days. About two-thirds of patients with SAH develop vasospasm, one-third develop DCI and one-sixth of SAH patients die or sustain permanent disability from DCI, despite aggressive medical/surgical intervention.

Nimodipine, a calcium-channel antagonist, is currently the only drug to convincingly improve outcomes after SAH. Randomized multi-centre clinical trials utilizing clazosentan, an endothelin receptor antagonist, demonstrated no change in clinical outcome despite significant decrease in large vessel vasospasm. These results have shifted the research in the pathophysiology of DCI to alternative mechanisms other than large vessel vasospasm.

It is known that the presence of blood in the subarachnoid space triggers massive local and systemic inflammation, including increase in the production of a pro-inflammatory cytokine called tumor necrosis factor alpha (TNFa). We have shown in mice that global, and smooth muscle-specific knockout of TNFa prevents increased myogenic tone and reduces brain injury after SAH. Furthermore, systemic or intrathecal treatment with etanercept may prevent the increase in myogenic tone observed after SAH and may reduce brain injury. Administration of etanercept to patients with SAH is a critical step in determining the safety and potential efficacy of TNFa antagonists in SAH. ;

Related Conditions & MeSH terms

• Hemorrhage
• Subarachnoid Hemorrhage
• Subarachnoid Hemorrhage, Aneurysmal

• NCT number: NCT01865630
• Study type: Interventional
• Source: St. Michael's Hospital, Toronto
• Status: Withdrawn
• Phase: Phase 1
• Start date: January 2021
• Completion date: January 2022