Clinical Literature

Penumbra System Bibliography.pdf

The Penumbra Stroke Trial

Safety and Effectiveness of a New Generation of Mechanical Devices for Clot Removal in Acute Ischemic Stroke.

Trial Design

Prospective, single arm, multi-center trial
Enrolled 125 patients at 24 international centers
Patients in the trial presented within 8 hours from symptom onset, had an NIH Stroke Scale (NIHSS) score of ≥ 8, and had a complete occlusion of a large intracranial vessel

Primary Endpoints

Revascularization of the occluded vessel
Procedure and device-related serious adverse events
Primary endpoints, as well as their comparative historical controls were prospectively defined and agreed upon with FDA prior to the start of the trial

Primary Endpoint Results

81.6% rate of revascularization (TIMI score 2 or 3) of the occluded vessel verses the 48.2% historical control¹ (p < 0.0001)
3.2% procedural serious adverse events (SAE) rate verses the 7.1% historical control¹
There were no device-related SAEs
No SAEs were attributed to device malfunction or breakage
All angiographic and clinical results were adjudicated and reviewed by an independent core laboratory, clinical events committee and safety monitoring board.

Secondary Endpoints & Results

Symptomatic intracerebral hemorrhage in 14 out of 125 (11.2%) patients
Asymptomatic intracerebral hemorrhage in 21 out of 125 (16.8%) patients
≥ 4 point improvement in NIHSS at discharge achieved by 57.8% of patients
modified Rankin Score (mRS) < 2 at 90 days achieved by 25% of patients
All cause mortality of 26.4% and 32.8% at 30 and 90 days respectively
The clinical and functional outcomes in this 125 patient cohort are in the range of previously published data on treatment outcomes in acute stroke
Penumbra is currently considering clinical trials with a randomized, concurrent control arm that would generate relevant data about the treatment effect of the Penumbra System on such clinical and functional endpoints.

The Effect of Revascularization

The 103 patients out of 125 (81.6%) whose intracranial vessels were opened by the Penumbra System had better results than the patients not revascularized across every measure of clinical and functional outcome including
- modified Rankin Score < 2 at 90 days
- ≥4 point improvement in NIHSS at discharge
- 30 and 90 day mortality
This finding confirms results from previously published studies that consistently demonstrate better outcomes for patients whose vessels are opened following a stroke, rather than remaining closed.

The abstract of the Penumbra System Trial was presented at the 2008 International Stroke Conference in New Orleans, LA.

1 Smith, et. al., Stroke 2005;36:1432