Field Administration of Stroke Therapy - Magnesium (FAST-MAG) Trial

Jeffrey L. Saver

Status and phase: Completed; Phase 3

Conditions: Cerebrovascular Accident

Treatments: Drug: Magnesium Sulfate; Drug: Normal Saline

Study type: Interventional

Funder types: Other; NIH

Identifiers

NCT00059332

U01NS044364 (U.S. NIH Grant/Contract)

Details and patient eligibility

About

The goal of this study is to evaluate the effectiveness and safety of field-initiated magnesium sulfate in improving the long-term functional outcome of patients with acute stroke.

Full description

Stroke is the third leading cause of death and the leading cause of adult disability in the United States. Each year, more than 750,000 Americans suffer a symptomatic stroke.

Currently, tissue plasminogen activator (rt-PA) is the only approved treatment for acute ischemic stroke; however, its usefulness is limited because most patients cannot reach medical attention within the necessary 3-hour time window. In addition, rt-PA cannot be given in the field because it is contraindicated for treatment of patients with brain hemorrhage.

The purpose of this multi-center, randomized, double-blind trial is to demonstrate that paramedic initiation of the neuroprotective agent magnesium sulfate in the field is an effective and safe treatment for acute stroke. This study will analyze magnesium sulfate, an experimental therapy for stroke, versus placebo among ambulance-transported patients with acute stroke. This trial will also demonstrate that paramedics can safely, effectively, and rapidly start neuroprotective therapies for stroke.

Enrollment: 1,700 patients

Sex: All

Ages: 40 to 95 years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• Suspected stroke identified by the Los Angeles Prehospital Stroke Screen
• Age 40-95, inclusive
• Last known well time within 2 hours of treatment initiation
• Deficit present for >/= 15 minutes

Exclusion criteria

• Coma
• Rapidly improving neurologic deficit
• Pre-existing neurologic, psychiatric, or advanced systemic disease that would confound the neurological or functional outcome evaluations
• Systolic Blood Pressure (SBP) < 90 or > 220
• Known severe renal dysfunction (on dialysis or known chronic creatinine > 3.0)
• Severe respiratory distress (O2 sat < 90% or respiratory rate < 12 or >/= 24)
• Known second or third degree heart block with no pacemaker in place
• Major head trauma in the last 24 hours
• Recent stroke within prior 30 days
• Patient unable to give informed consent and no available on scene consent or assent provider

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Quadruple Blind

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1,700 participants in 2 patient groups, including a placebo group

Magnesium Sulfate

Experimental group

Description:

Magnesium sulfate (Mg) was administered intravenously with a 15 minute bolus load followed by a 24 hour infusion. The bolus-loading dose consisted of 4 grams Mg in 54 ml normal saline. The maintenance infusion contained 16 grams Mg diluted in 240 ml 0.9% normal saline, infused at 10 ml/hr for 24 hours. Paramedics in the field initiated the bolus-loading dose, administered at 216 ml/hr over 15 minutes through a rate controlled IV infusion set. The maintenance infusion was initiated in hospital immediately upon completion of the loading dose.

Treatment:

Drug: Magnesium Sulfate

Normal saline

Placebo Comparator group

Description:

Normal saline was administered intravenously with a 15 minute bolus load followed by a 24 hour infusion. Paramedics in the field initiated the bolus-loading dose of 54 ml normal saline, administered at 216 ml/hr over 15 minutes through a rate controlled IV infusion set. The maintenance infusion was initiated in hospital immediately upon completion of the loading dose at 10 ml/hr for 24 hours.

Treatment:

Drug: Normal Saline