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Labetalol Versus Magnesium Sulfate (MgSO4) for the Prevention of Eclampsia Trial (LAMPET)

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details. Identifier: NCT00293735
Recruitment Status : Withdrawn (Lack of funding)
First Posted : February 17, 2006
Last Update Posted : January 13, 2017
Information provided by (Responsible Party):
Michael Belfort, Baylor College of Medicine

Brief Summary:
Eclampsia is a major cause of perinatal morbidity and mortality. The pathophysiology is not known but magnetic resonance imaging (MRI) and Doppler data suggest that overperfusion of the cerebral tissues is a major etiologic factor. Hypertensive encephalopathy from overperfusion, and vascular damage from excessive arterial pressure (cerebral barotrauma) are believed to lead to vasogenic and cytotoxic cerebral edema, with resultant neuronal anomalies, seizure activity and cerebral bleeding if left unchecked. Doppler data have shown that cerebral perfusion pressure (CPP) is abnormally increased in severe preeclampsia and that autoregulation of the middle cerebral artery is affected by this condition leading to increased CPP. Magnesium sulfate (MgSO4) is the most widely accepted eclampsia treatment and prophylactic agent, and it has been used in the USA since the 1950's. Despite widespread use, its mechanism of action is unknown. MgSO4 is given intravenously or intramuscularly and requires specialized nursing training and monitoring to minimize toxicity from respiratory and cardiac depression. Labetalol, a combined alpha and beta blocker, has been used for many years to safely treat hypertension in preeclamptic women, and is now known to reduce CPP in women with preeclampsia. In the United Kingdom labetalol was for many years used as the sole agent in treating preeclampsia, and the rate of seizure was no different to that reported in the USA with MgSO4. Since labetalol can be administered orally, is economical, has low toxicity potential, does not require specialized training to administer or monitor, and decreases CPP, it may be an ideal agent for controlling blood pressure (BP) and decreasing the incidence of eclampsia in women with preeclampsia. The current study is a multicenter, randomized, controlled trial to compare the anti-seizure effect of parenteral MgSO4 versus oral labetalol in hypertensive pregnant women who are eligible for MgSO4 therapy. The primary outcome measure is eclampsia, and the secondary outcome measures include blood pressure control, and relevant antenatal, intrapartum, and postnatal maternal and fetal/neonatal parameters including adverse effects and complications. Inclusion criteria are deliberately broad in order to make the study clinically relevant. Hypertensive pregnant women, in whom the decision for delivery has been made, will be enrolled after written, informed consent. Patients will be randomized to receive MgSO4 therapy as given in their institution, versus oral labetalol (200mg/q6 hours), from enrollment in the study until 24 hours post delivery. There will be 4000 patients in each arm of the study and analysis will be by intention-to-treat. The study is powered to show both therapeutic superiority as well as clinical equivalence. This study has the potential to change the way preeclampsia is managed, and will represent a major advance in terms of the availability and safety of prophylactic therapy, especially in developing nations where MgSO4 is underutilized due to cost constraints.

Condition or disease Intervention/treatment Phase
Preeclampsia Pregnancy Induced Hypertension Gestational Hypertension Chronic Hypertension Superimposed Preeclampsia Drug: labetalol (seizure prevention) Drug: MgSO4 (seizure prevention) Phase 2 Phase 3

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Study Type : Interventional  (Clinical Trial)
Actual Enrollment : 0 participants
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)
Primary Purpose: Prevention
Official Title: Labetalol Versus MgSO4 for the Prevention of Eclampsia Trial (LAMPET)
Study Start Date : June 2015
Actual Primary Completion Date : January 2017
Actual Study Completion Date : January 2017

Resource links provided by the National Library of Medicine

MedlinePlus related topics: Seizures

Arm Intervention/treatment
Active Comparator: 1. Labetolol Drug: labetalol (seizure prevention)

20mg IV (can be increased to an escalating dose of maximum of 80 mg (20mg, 40 mg, 80 mg q 20min) Cumulative max of 240 mg.

20mg labetalol PO every 6 hours

Active Comparator: 2. Magnesium Sulfate Drug: MgSO4 (seizure prevention)
4-6g bolus over 20 minutes; 1-2 grams/hr Discontinued 24 hours after delivery.

Primary Outcome Measures :
  1. Occurrence of eclamptic seizure(s) after enrollment in the study. [ Time Frame: 24 Hours Postpartum ]

Secondary Outcome Measures :
  1. Maternal: Blood pressure, pulse pressure and heart rate changes [ Time Frame: 24 hours postpartum ]
  2. Need for additional antihypertensive medication (defined by need to control BP > 160 mmHg systolic and/or 110 mmHg) [ Time Frame: 24 hours postpartum ]
  3. Subjective assessment of side effects by the patient [ Time Frame: 24 hours postpartum ]
  4. Objective assessment of new onset complications and/or side effects by the treating clinicians [ Time Frame: 24 hours postpartum ]
  5. Labor and delivery parameters including; induction to delivery interval, rate of cervical dilatation, oxytocin dosages, length of labor, delivery route, blood loss at delivery, and postpartum course; and [ Time Frame: 24 hours postpartum ]
  6. Type of anesthesia administered (none, local infiltration for delivery only, epidural for labor, epidural for delivery, spinal for delivery, combined/spinal epidural for labor and delivery, general anesthesia for delivery). [ Time Frame: 24 hours postpartum ]
  7. Fetal and Neonatal: Occurrence of newly diagnosed fetal distress during labor necessitating emergent delivery [ Time Frame: 24 hour postpartum ]
  8. Umbilical cord gases at delivery (if available in institution) [ Time Frame: 30 minutes after delivery ]
  9. Apgar scores; and [ Time Frame: 1min and 5 minutes after delivery ]
  10. Neonatal outcome as defined by NICU admission, hospital survival to discharge, length of hospital survival, days in NICU, need for blood transfusion, need for pressor agents, need for mechanical ventilation, neonatal cardiac dysrhythmias, [ Time Frame: Discharge from hospital ]
  11. neonatal cardiac failure, necrotizing enterocolitis, sudden infant death, neonatal sepsis, neonatal hypoglycemia, and there will be an other block for recording any other identified complications not mentioned. [ Time Frame: discharge from hospital ]

Information from the National Library of Medicine

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Ages Eligible for Study:   15 Years to 60 Years   (Child, Adult)
Sexes Eligible for Study:   Female
Accepts Healthy Volunteers:   No

Inclusion Criteria:

  • Any patient with preeclampsia (BP > 140 systolic and/or > 90 mmHg diastolic with 1+ or more proteinuria [or a 24 hour specimen with > 300 mg/day]), chronic hypertension (or superimposed preeclampsia), or gestational hypertension deemed to be at risk for eclamptic convulsions and who would routinely be treated in the participating institution with some form of anti-seizure prophylaxis during labor and delivery.

Exclusion Criteria:

  • Any patient for whom informed consent cannot be obtained.
  • Any patient who has received an antihypertensive medication within 6 hours prior to enrollment will not be eligible but those who have received antihypertensive medications other than beta-blockers or magnesium sulfate may still be enrolled as long as they have not been given a dose within the 6 hours prior to enrollment. If a patient has received MgSO4 or a short acting beta-blocker or calcium channel blocker more than 12 hours prior to enrollment or if they have received a long acting beta-blocker more than 24 hours before enrollment she may still be considered eligible. This stipulation will allow increased recruitment of patients especially those with chronic hypertension and those transferred from outlying institutions. We expect these patients to be a minority of the enrollment.
  • A history of bronchial asthma, emphysema, heart block, angina, cardiomyopathy or myocardial infarction.
  • Any history or signs of congestive cardiac failure, or arrhythmia with a ventricular rate of less than 60 bpm.
  • Patients with severe mental or physical disorders which, in the opinion of the investigators, might affect responsiveness to therapy or any other aspect of the study.
  • Patients who are allergic to drugs with a chemical structure similar to labetalol or magnesium sulfate.
  • Patients given magnesium sulfate, labetalol or short acting beta blockers or calcium channel blockers less than 12 hours prior to enrollment in the study.
  • Evidence of fetal distress or fetal anomalies.
  • Inability to secure intravenous access.
  • Patient's primary physician declines to enroll patient in study.

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its identifier (NCT number): NCT00293735

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United States, Texas
Baylor College of Medicine
Houston, Texas, United States, 77030
Institute of Maternal and Child Health Medicine
Kerala, India, 673008
Sponsors and Collaborators
Baylor College of Medicine
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Principal Investigator: Michael A Belfort, MD, PhD Baylor College of Medicine


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Responsible Party: Michael Belfort, Chairman and Professor, Baylor College of Medicine Identifier: NCT00293735    
Other Study ID Numbers: H-28505
First Posted: February 17, 2006    Key Record Dates
Last Update Posted: January 13, 2017
Last Verified: January 2017
Keywords provided by Michael Belfort, Baylor College of Medicine:
HELLP Syndrome
Additional relevant MeSH terms:
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Hypertension, Pregnancy-Induced
Vascular Diseases
Cardiovascular Diseases
Pregnancy Complications
Adrenergic beta-Antagonists
Adrenergic Antagonists
Adrenergic Agents
Neurotransmitter Agents
Molecular Mechanisms of Pharmacological Action
Physiological Effects of Drugs
Antihypertensive Agents
Autonomic Agents
Peripheral Nervous System Agents
Adrenergic alpha-1 Receptor Antagonists
Adrenergic alpha-Antagonists