Magnetically Enhanced Diffusion for Acute Ischaemic Stroke (MEDIS) Trial

The objective of the MEDIS study is to determine if subjects experiencing an Acute Ischaemic Stroke due to large vessel occlusion, treated with IV tPA combined with the MED procedure have a greater likelihood of recanalisation 30-90 minutes after the completion of tPA infusion than subjects treated with IV tPA (plus sham device). Safety of the MED System Procedure will be evaluated by the incidence of symptomatic PH-2 haemorrhagic transformation within 24 hours following the procedure. Lastly, a health economics study will be conducted to estimate health care costs for each treatment.

The study is a global, multicentre prospective, randomised, single blind, blinded endpoint study comparing rates of early recanalisation (defined by mAOL) in Acute Ischaemic Stroke (AIS) subjects with visible occlusion who are treated with either IV tPA plus sham device or IV tPA in combination with the MED System procedure.

The study population will be randomised 1:1 into two arms:

* A Sham Control Group (SCG) and an
* Experimental Treatment Group (ETG).

The ETG will receive IV tPA and the complete MED System procedure consisting of MED MicroBeads and the MED Workstation magnet procedure. The SCG will not receive MED MicroBeads while the MED Workstation will be activated as a Sham control. Subjects will be blinded to treatment arm. Stratification will be performed based upon baseline age and location of the occlusion (Middle Cerebral Artery segments M1, M2, or Carotid Terminus).

Eligibility Criteria:
Inclusion Criteria:

1. Age ≥18 and \<85
2. Clinical signs consistent with acute ischaemic stroke
3. Prestroke functional independence (prestroke Modified Rankin Score ≤2)
4. NIHSS 4-25 at the time of randomisation
5. Initiation of IV tPA (alteplase or tissue Plasminogen Activator) within the locally approved time window from stroke symptom onset (onset time is defined as the last time when the subject was witnessed to be at baseline).
6. Arterial Occlusive Lesion (mAOL ≤1) in the M1 or M2 segments of the MCA (Middle Cerebral Artery) or carotid terminus confirmed by CT angiography.
7. Subject is able to start the MED procedure within 15 +10 minutes) from the t-PA IV infusion, and complete 60+15 minutes of MED procedure treatment.
8. Subject or subject's legally authorised representative has signed and dated an Informed Consent Form according to country regulations, ethics committee, and/or Institutional Review Board requirements.
9. It is the enrolling Investigator's or designee's opinion based upon the knowledge of the Subject's condition as well as the features of the MED device, that the Subject is an appropriate candidate for stroke management utilizing MED.

Exclusion Criteria:

1. The subject is likely to receive intra-arterial (IA) intervention.
2. Standard exclusions for thrombolysis according to the approved label and local institutional protocols.
3. Female who is pregnant or lactating or has a positive pregnancy test at time of admission.
4. Rapid neurological improvement prior to study randomisation suggesting resolution of the occlusion.
5. Known hyper-sensitivity to radiographic contrast agents.
6. Known hyper-sensitivity to iron-based agents or polyethylene glycol.
7. Known or suspected symptomatic haemosiderosis or haemochromatosis.
8. Has a previous or existing cardiovascular condition resulting in history of heart block, tachybrady syndrome, symptomatic postural hypotension requiring medical intervention.
9. Current participation or participation in the last 4 weeks in another investigational drug or device treatment study.
10. Life expectancy of less than 90 days due to other medical condition.
11. Subject with a pre-existing neurological or psychiatric disease that would confound the neurological and functional evaluations.
12. Subject has contraindications to Magnetic Resonance Imaging (MR; examples include, but are not limited to, an implantable cardioverter defibrillator, pacemaker, clipped or coiled aneurysm, neurostimulator).
13. Subject has recently (within 30 days) received iron replacement therapy or iron based MR contrast.
14. Subject has known or suspected liver disease, including hepatitis and/or cirrhosis.

Imaging Exclusion Criteria:

1. Computed tomography (CT) or MRI evidence of haemorrhage on presentation.
2. Exclusion: Large core of ischemia defined as NCCT ASPECTS 4 or less.
3. CT or MRI evidence of mass effect or intra-cranial tumour (except small meningioma).
4. CTA or MRA (CT or MR Angiography) evidence of carotid dissection or complete cervical carotid occlusion.