A Safety Evaluation of the Use of Magnetic-guided Iron Particles

Inclusion Criteria: * Subject is between 18 and 80 years of age. * Subject has moderate to large (NIHSS ≥ 10 and ≤24) ischemic stroke * Subject has an intracranial arterial occlusion of the middle cerebral artery (MCA), anterior cerebral artery (ACA), internal carotid artery (ICA), posterior cerebral artery (PCA) or distal basilar artery confirmed by CT or MR angiography. * Subject is eligible for initiation of intravenous tPA within three hours of stroke onset, where time of stroke onset is defined as the last time the patient was witnessed to be at baseline. Exclusion Criteria: * Subject has known sensitivity to iron or PEG products. * Subject has recently (within 30 days) received iron replacement therapy. * Subject has known or suspect liver function abnormality. * Subject has known or suspect severe renal impairment. * Subject has a high-density lesion on baseline CT scan consistent with hemorrhage of any degree. * Subject has a significant mass on baseline CT consistent with midline shift. * Subject has a large (greater than one-third of the middle cerebral artery) regions of clear hypodensity on the baseline CT scan. * Subject has evidence of intraparenchymal tumor on baseline CT scan. * Subject experiences a seizure at the onset of stroke. * Subject has known hemosiderosis or hemochromatosis. * Subject has an implantable cardioverter defibrillator, pacemaker, neurostimulator or other device incompatible with MRI. * Subject has a history of stroke within the last three months. * Subject has a previous or existing intracranial hemorrhage, neoplasm, subarachnoid hemorrhage or arteriovenous malformation. * Subject has experienced any active or recent (within 30 days) hemorrhage. * Subject has systolic blood pressure \> 185 mmHg or diastolic \> 110 mmHg. * Subject has presumed septic embolus or suspicion of bacterial endocarditis. * Subject has presumed pericarditis including pericarditis after acute myocardial infarction. * Subject is suspected to have an aortic dissection. * Subject has recently (within 30 days) undergone surgery or biopsy of a parenchymal organ. * Subject has recently (within 30 days) experienced trauma with internal injuries or ulcerative wounds. * Subject has recently (within 90 days) experienced severe head trauma with loss of consciousness. * Subject has known hereditary or acquired hemorrhage diathesis, coagulation factor deficiency, or oral anticoagulant therapy with INR \> 1.7 or institutionally equivalent prothrombin time. * Subject has a glucose level of \< 50 mg/dl or \>400 mg/dl, or a platelet count less than 100,000, or an Hct level less than 25. * Subject has taken dabigatran within the last 48 hours or any new anticoagulant which cannot be monitored by traditional. * Subject requires hemodialysis or peritoneal dialysis, or has a contraindication to angiogram. * Subject has prolonged partial thromboplastin time (PTT) (in the case where heparin or a direct thrombin inhibitor has been administered within 48 hours). * Subject has had a recent (within 7 days) lumbar puncture or arterial puncture at a non-compressible site. * Subject has a pre-existing neurological or psychiatric disease that would confound evaluations. * Subject is pregnant, nursing or intends to become pregnant during the trial period. * Subject is currently enrolled in other potentially confounding research. * Subject has any condition that, at the discretion of the investigator, would preclude participation in the trial.