Nicardipine implants following subarachnoid hemorrhage

This phase II study evaluated the efficacy of nicardipine prolonged-release implants (NPRIs) in the management of cerebral vasospasm following a hemorrhagic stroke.

Following a hemorrhagic stroke (rupture of a blood vessel leading to impaired blood supply to the brain; know as ischemia) blood vessels in the area of the bleeding may involuntary contract and narrow, leading to severe ischemia and an increased mortality risk. This is referred to as cerebral vasospasm, and is a common complication among hemorrhagic stroke patients.  Nicardipine belongs to a class of drugs referred to as calcium channel blockers, which can relax and widen blood vessels, ensuring proper blood flow through the narrowed artery. NPRIs (nicardipine prolonged-release implants) are a newly developed intervention in which an implant containing nicardipine is inserted into the blood vessel during the treatment of the hemorrhage.

This study included 32 patients treated for a severe subarachnoid hemorrhagic stroke. Patients were randomized to receive either standard care, or standard care with insertion of a NPRI.

One week following treatment, patients receiving a NPRI exhibited a significantly reduced incidence of cerebral vasospasm near the area of the hemorrhagic stroke. Only 7% of patients receiving a NPRI showed vasospasm on cerebral imaging scans, compared to 73% of patients in the control group. Imaging scans also revealed a lower incidence of delayed ischemic lesions (findings which indicate ongoing disruption to cerebral blood flow). 47% of control patients exhibited delayed ischemic lesions compared to only 14% of patients receiving a NPRI. Clinical scoring scales (methods of measuring the severity of the stroke or additional risks, such as the Rankin scale, or the National Institute of Health Stroke scale) also demonstrated clearly superior clinical outcomes with the use of NPRIs. One year following treatment, the incidence of death was also significantly reduced among patients receiving a NPRI. Mortality rates were 38% among control patients, compared to only 6% among patients receiving a nicardipine implant.

This study concluded that nicardipine prolonged-release implants reduce the incidences of cerebral vasospasm and significantly improve clinical outcomes among subarachnoid hemorrhagic stroke patients.

Results of this initial early phase trial should be confirmed in larger phase III trials before NPRI enter common clinical practice.