This study will determine if NXY-059 will improve recovery from an acute stroke. The study is designed to look at both overall recovery and recovery of motor function, for example muscle strengthen and coordination.

Inclusion Criteria:

• Males and females
• Acute ischemic stroke with limb weakness
• Onset of symptoms within 6 hours
• Full functional independence prior to the present stroke

Exclusion Criteria:

• Unconsciousness
• Subjects who are unlikely to complete the infusion of investigational product and/or are unlikely to undergo active medical management during that period due to a severe clinical condition.
• Severe illness with life expectancy less than 6 months.
• Known severe kidney disorder.
• Current known alcohol or illicit drug abuse or dependence.
• Pregnant or breast-feeding.
• Treatment with acetazolamide and methotrexate is not permitted during the infusion
• Participation in a previous clinical study within 30 days.
• Meets all other exclusion criteria.