• Primary Effectiveness Endpoint: Patients with a Modified Rankin Scale (mRS) </= 2 [ Time Frame: 90 (+/-15) days ]
  Global disability assessed via the blinded evaluation of the proportion of patients with a Modified Rankin Scale (mRS) </= 2
• Primary Safety Endpoint: Device- or procedure-related symptomatic intracerebral hemorrhage (sICH) [ Time Frame: 24 (-8/+12) hours ]
  Proportion of subjects with device- or procedure-related symptomatic intracerebral hemorrhage (sICH)

• Primary Effectiveness Endpoint: Patients with a Modified Rankin Scale (mRS) < 2 [ Time Frame: 90 (+/-15) days ]
  Global disability assessed via the blinded evaluation of the proportion of patients with a Modified Rankin Scale (mRS) < 2
• Primary Safety Endpoint: Device- or procedure-related symptomatic intracerebral hemorrhage (sICH) [ Time Frame: 24 (-8/+12) hours ]
  Proportion of subjects with device- or procedure-related symptomatic intracerebral hemorrhage (sICH)

• Successful Revascularization measured using the expanded Thrombolysis in Cerebrovascular Infarction (eTICI) [ Time Frame: During Index Procedure ]
  Proportion of subjects with eTICI 2b50 or greater flow in the target vessel post procedure with 3 or fewer passes of the assigned study device.
• Successful Revascularization on first pass measured using the expanded Thrombolysis in Cerebrovascular Infarction (eTICI) [ Time Frame: During Index Procedure ]
  Proportion of patients with eTICI 2c or greater, following the first pass of the assigned study device
• Overall mortality following the index stroke [ Time Frame: 90 (+/-15) days ]
  Overall mortality following the index stroke
• Distribution of mRS shift across the entire spectrum of disability [ Time Frame: 90 (+/-15) days ]
  Distribution of mRS shift across the entire spectrum of disability

• Successful Revascularization measured using the expanded Thrombolysis in Cerebrovascular Infarction (eTICI) [ Time Frame: During Index Procedure ]
  Difference in proportion of subjects with eTICI 2b50 or greater flow in the target vessel post procedure with 3 or fewer passes of the assigned study device.
• Successful Revascularization on first pass measured using the expanded Thrombolysis in Cerebrovascular Infarction (eTICI) [ Time Frame: During Index Procedure ]
  Proportion of target vessels with first-pass eTICI 2c or greater, separately per group and difference in these proportions, with 3 or fewer passes of the assigned study device
• Successful Revascularization measured per group using the expanded Thrombolysis in Cerebrovascular Infarction (eTICI) [ Time Frame: During Index Procedure ]
  Final eTICI 2b50 or greater and eTICI 2c or greater proportions per group and differences in proportions.
• Successful Revascularization on first pass per group measured using the expanded Thrombolysis in Cerebrovascular Infarction (eTICI) [ Time Frame: During Index Procedure ]
  Proportion of target vessels with first-pass eTICI 2b50, 2b67, 2c or 3, per group and comparison of proportions.
• Early Response [ Time Frame: Day 7 / Discharge (whichever is earlier) ]
  Proportion of subjects with "early response", defined as a NIHSS drop of ≥10 points from baseline or NIHSS score 0 or 1.
• Occurrence of all intracranial hemorrhage [ Time Frame: 24 (-8/+12) hours ]
  All intracranial hemorrhages using the Heidelberg Bleeding classification.
• Occurrence of stroke related and all-cause mortality [ Time Frame: 90 (+/-15) days ]
  Stroke-related mortality and overall mortality
• Neurological deterioration [ Time Frame: Day 7 / Discharge (whichever is earlier) ]
  Incidence of neurological deterioration from baseline NIHSS score through Day 7/discharge (whichever is earlier) post treatment (time zero). Neurological deterioration is defined as ≥ 4-point increase in the NIHSS score from the baseline score.
• Occurrence of procedure-related and device-related Serious Adverse Events [ Time Frame: 24 (-6/+24) hours ]
  Incidence of procedure-related and device-related serious adverse events (PRSAEs and DRSAEs) as adjudicated by the clinical events committee, and defined as:

  1. Vascular perforation
  2. Intramural arterial dissection
  3. Embolization to a new territory
  4. Access site complication requiring surgical repair or blood transfusion
  5. Intra-procedural mortality
  6. Device failure (in vivo breakage)
  7. Any other complications adjudicated by the CEC to be related to the procedure

• Brain Diseases
• Cardiovascular Diseases
• Central Nervous System Diseases
• Cerebrovascular Disorders
• Ischemia
• Nervous System Diseases
• Pathologic Processes
• Stroke, Ischemic
• Stroke, Acute
• Vascular Diseases

• Device: Mechanical Thrombectomy using the pRESET Thrombectomy device
  Clot removal using the pRESET Thrombectomy device
• Device: Mechanical Thrombectomy using the Solitaire Revascularization Device
  Clot removal using the Solitaire Revascularization Device

• Experimental: pRESET Thrombectomy Device
  Mechanical Thrombectomy using the pRESET Thrombectomy Device
  Intervention: Device: Mechanical Thrombectomy using the pRESET Thrombectomy device
• Active Comparator: Solitaire Revascularization Device
  Mechanical Thrombectomy using the Solitaire Revascularization Device
  Intervention: Device: Mechanical Thrombectomy using the Solitaire Revascularization Device

Inclusion Criteria:

1. Age >/=18
2. Clinical signs consistent with acute ischemic stroke
3. Subject is able to be treated within 8 hours of stroke symptom onset and within 1.5 hours (90 min) from screening CT / MRI to groin puncture.
4. Pre-stroke modified Rankin Score of 0 or 1
5. NIHSS ≥6 at the time of enrolment
6. If tPA is indicated, initiation of IV tPA should be administered as soon as possible and no later than 3.0 hours of onset of stroke symptoms (onset time is defined as the last time when the patient was witnessed to be at baseline neurologic status), with investigator verification that the subject has received/is receiving the correct IV tPA dose (0.9mg/kg) for the estimated weight.

7. Expanded Thrombolysis in Cerebral Infarction (eTICI) 0-1 flow confirmed by angiography that is accessible to the mechanical thrombectomy device in the following locations:

   1. Intracranial internal carotid
   2. M1 and/or M2 segment of the MCA
   3. Carotid terminus
   4. Vertebral artery
   5. Basilar artery

   Note: M1 segment of the MCA is defined as the arterial trunk from its origin at the ICA to the first bifurcation or trifurcation into major branches neglecting the small temporo-polar branch.

8. Imaging scores as follows:

   · ASPECTS score must be 6-10 on NCCT or DWI-MRI.

   If automated core volume assessment software is used:

   • MR diffusion-weighted imaging (DWI) ≤50cc
   • Computed tomography perfusion (CTP) core ≤50 cc
9. Subject is willing to conduct protocol-required follow-up visits.
10. A valid completed informed consent by participant or LAR (Legally Authorized Representative)

Exclusion Criteria:

1. Subject who has received IA-tPA prior to enrolment in the study
2. Female who is pregnant or lactating or has a positive pregnancy test at time of admission.
3. Rapid neurological improvement prior to study enrolment suggesting resolution of signs/symptoms of stroke
4. Known serious sensitivity to radiographic contrast agents
5. Known sensitivity to nickel, titanium metals, or their alloys
6. Subjects already enrolled in other investigational studies that would interfere with study endpoints
7. Known hereditary or acquired hemorrhagic diathesis, coagulation factor deficiency. (A subject without history or suspicion of coagulopathy does not require INR or prothrombin time lab results to be available prior to enrolment.)
8. Known renal failure as defined by a serum creatinine > 2.0 mg/dl (or 176.8 μmol/l) or glomerular filtration rate (GFR) < 30.
9. Subject who requires hemodialysis or peritoneal dialysis, or who has a contraindication to an angiogram for whatever reason.
10. Life expectancy of less than 90 days
11. Clinical presentation suggests a subarachnoid hemorrhage, even if initial CT or MRI scan is normal
12. Suspicion of aortic dissection
13. Subject with a comorbid disease or condition that would confound the neurological and functional evaluations or compromise survival or ability to complete follow-up assessments.
14. Subject is known to currently use or has a recent history of illicit drug(s) or abuses alcohol (defined as regular or daily consumption of more than four alcoholic drinks per day).
15. Known arterial condition (e.g., proximal vessel stenosis or pre-existing stent) that would prevent the device from reaching the target vessel and/or preclude safe recovery of the device
16. Subject who requires balloon angioplasty or stenting of the carotid artery at the time of the index procedure

17. Angiographic evidence of carotid dissection

    Imaging exclusion criteria:

18. CT or MRI evidence of hemorrhage on presentation
19. CT or MRI evidence of mass effect or intra-cranial tumor (except small meningioma)
20. CT or MRI evidence of cerebral vasculitis
21. CT or MRI-DWI showing ASPECTS 0-5. Alternatively, if automated core volume assessment software is used, MRI-DWI or CTP core > 50cc.
22. CT/MRI shows evidence of carotid dissection or complete cervical carotid occlusion requiring a stent
23. Any imaging evidence that suggests, in the opinion of the investigator, the subject is not appropriate for mechanical thrombectomy intervention (e.g. inability to navigate to target lesion, moderate/large infarct with poor collateral circulation, etc.).
24. Occlusions in multiple vascular territories (e.g., bilateral anterior circulation, or anterior/posterior circulation) as confirmed by angiography, or clinical evidence of bilateral strokes or strokes in multiple territories