Title

VISSIT Intracranial Stent Study for Ischemic Therapy
Phase III Study of Pharos Vitesse Neurovascular Stent System Compared to Best Medical Therapy for the Treatment of Ischemic Disease
  • Phase

    Phase 2/Phase 3
  • Study Type

    Interventional
  • Intervention/Treatment

    acetylsalicylic acid clopidogrel ...
  • Study Participants

    125
The main objective of this study is to prospectively evaluate the safety, probable benefit, and effectiveness of the PHAROS Vitesse Neurovascular Stent System in a multicenter, randomized clinical trial.

A secondary objective of this study is to evaluate the impact of stenting in the neurovasculature to treat cerebral ischemia on other outcomes such as hospital length of stay, charges, and costs.
1.1 Study Hypothesis Treatment of cerebral or retinal ischemia due to plaque in the neurovasculature using the PHAROS Vitesse Stent System plus medical therapy will provide additional clinical benefit over medical therapy alone.

1.2 Primary Effectiveness Endpoint

The primary effectiveness endpoint consists of a composite of the two following outcomes:

Stroke in the same territory (distal to the target lesion) as the presenting event within 12 months of randomization
Hard TIA in the same territory (distal to the target lesion) as the presenting event from day 2 through month 12 post-randomization

1.3 Safety Outcomes

Safety outcomes to be collected and reported as part of the overall risk-to-benefit profile for this device are:

Stroke in any territory within 30 days of randomization
Death from any cause within 30 days of randomization
Hard TIA in any territory occurring after a 24 hour post-procedure stabilization period (days 2-30) since the recovery from anesthesia can mask accurate assessment of possible TIA symptoms.
Intracranial hemorrhage within 30 days of randomization

1.4 Other Outcomes

Stent Success - PHAROS Vitesse stent deployed across target lesion with residual stenosis 0-20%
Percentage of Stent Group Subjects with any (symptomatic or asymptomatic) in-stent restenosis ≥ 70% confirmed by angiogram at 12 months
Percentage of Stent Group Subjects with symptomatic in-stent restenosis ≥ 70% confirmed by angiogram at 12 months
Percentage of Medical Therapy Group Subjects with interventional procedure (e.g., angioplasty or stent) at 12 months
Comparison of NIHSS scores between treatment arms
Comparison of mRS scores between treatment arms
Study Started
Oct 31
2008
Primary Completion
Apr 30
2013
Study Completion
Jun 30
2014
Results Posted
Jun 16
2014
Estimate
Last Update
Feb 20
2015
Estimate

Device Pharos Vitesse Neurovascular Stent System (Stent implantation) + Medical therapy (Aspirin and Clopidogrel)

Implantation of one or more balloon-expandable Pharos Vitesse stents to treat neurovascular ischemic lesions + Medical therapy [Treatment with aspirin (81-325 mg daily for the duration of the study) and Clopidogrel (75 mg daily for first 3 months)]

  • Other names: Pharos Vitesse Neurovascular Stent System, Asprin, Clopidogrel, Plavix(r)

Drug Aspirin and Clopidogrel (Medical therapy)

Medical therapy alone [Treatment with aspirin (81-325 mg daily for the duration of the study) and Clopidogrel (75 mg daily for first 3 months)]

  • Other names: Aspirin, Clopidogrel, Plavix(r)

Stent Group Experimental

Medical therapy + PHAROS Vitesse neurovascular stent ("Stent Group")

Medical Therapy Group Active Comparator

Medical therapy alone ("Medical Therapy Group")

Criteria

Inclusion Criteria:

Subject has at least one neurovascular lesion (70-99%) stenosis [internal carotid, middle cerebral, vertebral artery (C4-BA), and/or basilar artery] symptomatic with a hard TIA or stroke attributable to the territory of the lesion within the past 30 days. An intracranial tandem lesion (50-99%) stenosis may be treated if normal artery segment is sufficient length to avoid overlapping stents.

Target vessel diameter / lesion length measurements are within one of the below per angiogram:

Vessel diameter is ≥ 2.0 mm and < 2.5 mm / lesion length is ≤ 16 mm, or
Vessel diameter is ≥ 2.5 mm and < 3.0 mm / lesion length is ≤ 18 mm, or
Vessel diameter is ≥ 3.0 mm and < 4.5 mm / lesion length is ≤ 26 mm, or
Vessel diameter is ≥ 4.5 mm and ≤ 5.0 mm / lesion length is ≤ 31 mm
Subject has normal artery adjacent to each stenosis; diameter 2.0 mm - 5.0 mm
Subject age is 18-85 years
Life expectancy is at least 2 years
Subject 's mRS score is ≤ 3
Subject is available for study follow-up visits (e.g., lives within 3 hours of research center)
Subject is willing and cognitively able to provide Informed Consent (consent may be indicated verbally and signed by neutral witness if stroke has impaired hand or visual function)

Exclusion Criteria:

Subject has contraindications for balloon expandable stent, e.g.

Extreme tortuosity at, or proximal to, target lesion,
More than 2 lesions with > 50% stenosis (including vertebral ostia and common carotid disease),
Carotid or vertebral dissection

CT scan or MRI evidence of any of the following:

Intracranial hemorrhage of type PH1 or PH2
Subdural or epidural hemorrhage
Mass effect, or
Intracranial tumor (except small meningioma)
Subject has a previous stent in the territory of the target lesion(s)
Subject has a previous coil or clip placed in the territory of the target lesion within 6 months
Subject has a potential source of cardiac embolism requiring anticoagulation therapy (e.g., atrial fibrillation, intracardiac thrombus or vegetation, significant mitral stenosis, mechanical heart valve, congestive heart failure with EF <30%, or endocarditis)

Subject has concurrent intracranial pathology, e.g.

Moyamoya
Vasculitis documented by biopsy results
Ruptured Aneurysm
Unruptured aneurysm > 7mm
Subject has uncontrolled hypertension (systolic >185 mmHg or diastolic >110 mmHg)
Hemoglobin < 10 g/dL; platelet count < 100,000; or INR > 1.5 (e.g., use of warfarin)
Subject has an uncorrectable bleeding diathesis
Subject's neurological status is unstable and rapidly declining (NIHSS score increased > 4 points within 48 hours prior to randomization)
Subject has a contraindication for combination antithrombotic treatment (e.g., clopidogrel and aspirin) such as peptic ulcer disease
Subject history indicates high risk of non-compliance (e.g., substance abuse, psychosocial issues, etc.)
Subject has a known history contraindicating contrast dye or iodine (vs. sensitivity which can be safely controlled by antihistamine, steroid, etc.)
Subject is pregnant or plans to become pregnant in the next 12 months
Myocardial infarction within past 3 months
Treatment with tPA or other thrombolytic agent within 48 hours prior to randomization
Major surgery or trauma within 2 weeks prior to randomization
Enrollment in another investigational device or drug study that may confound the results

Summary

Stent Group

Medical Therapy Group

All Events

Event Type Organ System Event Term Stent Group Medical Therapy Group

Successful Outcome: No Stroke or Hard TIA in the Same Territory Within 12 Months

The primary effectiveness endpoint was a composite of the two following outcomes: Stroke in the same territory (distal to the target lesion) as the presenting event within 12 months of randomization Hard Transient Ischemic Attack (TIA) in the same territory (distal to the target lesion) as the presenting event from day 2 through month 12 post-randomization A subject was deemed to be a primary endpoint success if neither of these outcomes occurred. The Kaplan-Meier success rate at 12-months post-operatively was calculated with Kaplan-Meier time-to-event methodology, where the time variable for patients who were successful (no stroke within 12 months or hard TIA between 2 days and 12 months) was censored at the time of last follow-up, and the time variable for patients who were not successful (had a stroke within 12 months or hard TIA between 2 days and 12 months) was censored at the time of the first event (stroke with 12 months or hard TIA between 2 days and 12 months).

Stent Group

62.24
percent probability
95% Confidence Interval: 48.15 to 73.15

Medical Therapy Group

83.68
percent probability
95% Confidence Interval: 69.94 to 91.5

Total

111
Participants

Age, Continuous

61.8
years (Mean)
Standard Deviation: 12.5

Ethnicity (NIH/OMB)

Race/Ethnicity, Customized

Region of Enrollment

Sex: Female, Male

Overall Study

Stent Group

Medical Therapy Group

Drop/Withdrawal Reasons

Stent Group

Medical Therapy Group