A Study to Assess the Efficacy, Safety, and Pharmacokinetics of TB006 in Participants With Acute Ischemic Stroke

Inclusion Criteria:

1. Body Mass Index (BMI) between 18 and 40 kilograms per meters squared (kg/m^2), inclusive
2. Clinical diagnosis of AIS in anterior circulation, supported by evidence of a new stroke on acute brain computed tomography (CT) or magnetic resonance imaging (MRI) consistent with the clinical diagnosis.
3. Able to be randomized and dosed within 7 days of index stroke event. The last known awake time will be used for participants whose stoke occurred during sleep.
4. National Institute of Health Stroke Scale total score of 7 to 21, inclusive
5. Participants may have received standard of care therapy including recombinant tissue plasminogen activator (r-tPA), thrombectomy, mannitol, hypertonic saline, and other treatments per local guidelines as determined by the Investigator. Participants who have received r-tPA within the first day of their stroke event are eligible. However, study drug administration must begin more than 24 hours following r-tPA administration.

Exclusion Criteria:

1. Evidence of severe stroke on imaging (e.g., sulcal effacement or blurring of gray-white junction in greater than 1/3 of middle cerebral artery [MCA] territory, Alberta Stroke Program Early CT [ASPECT] score of 0 to 4 based on head CT, acute infarct volume on MRI diffusion weighed imaging ≥70 mL based on acute imaging studies performed under the standard of care
2. Lacunar or isolated brainstem or cerebellar stroke based on clinical assessment and available acute imaging studies performed under the standard of care
3. Evidence of seizure at the onset of index stroke

Evidence of acute myocardial infarction (MI) at Baseline, including any of the following:

1. Acute ST elevation MI;
2. Acute decompensated heart failure, or New York Heart Association Class III/IV heart failure;
3. Admission for an acute coronary syndrome, MI, cardiac arrest, or non-voluntary coronary intervention (percutaneous coronary intervention or coronary artery surgery) within the past 3 months.
4. QT interval corrected using Bazett's formula (QTcB) >520 milliseconds (msec).
5. Evidence of acute intracranial or subarachnoid hemorrhage or evidence of active bleeding based on acute brain CT or MRI performed under the standard of care. However, petechial hemorrhages of ≤ 1 centimeter (cm) are not exclusionary.

Note: Other protocol defined Inclusion/Exclusion criteria may apply.