This trial is active, not recruiting.

Condition guillain-barre syndrome
Sponsor Harvard Pilgrim Health Care
Collaborator Aetna, Inc.
Start date March 2005
End date August 2008
Trial size 6000000 participants
Trial identifier NCT00575653, PH000274A


We are conducting a large, record-based study to assess the risk of Guillain-Barré Syndrome (GBS), a serious demyelinating disease, following immunization with the tetravalent meningococcal conjugate vaccine (Menactra) that is currently recommended for all adolescents. The study was requested by CDC and FDA because of an unexpected number of case reports to the CDC's Vaccine Adverse Event Reporting System (VAERS).

The study protocol was designed by the investigators, with input from FDA, CDC, and the vaccine's manufacturer, Sanofi-Pasteur. An external advisory board that includes CDC representation, provides input regarding important decisions. The manufacturer is not participating in the conduct of the study and has no control over the analysis or dissemination of results.

The study is derived from five large US health plans with a total membership of approximately 50 million over the study time period. America's Health Insurance Plans (AHIP) serves as liaison between the health plans and the Coordinating Center at the Department of Ambulatory Care and Prevention of Harvard Medical School and Harvard Pilgrim Health Care, and is the contracting organization with the health plans.

United States No locations recruiting
Other countries No locations recruiting

Study Design

Observational model cohort
Time perspective retrospective
Enrolled members of one of the participating health plans who are ages 11-18 at any time during the study period, March 1, 2005 through August 31, 2008.
Enrolled members of one of the participating health plans who are ages 19-21 at any time during the study period, March 1, 2005 through August 31, 2008.

Primary Outcomes

Guillain-Barré syndrome (GBS), verified through neurologist review of medical records
time frame: within 42 days following vaccination

Secondary Outcomes

Clinical presentation and severity of GBS
time frame: following vaccination

Eligibility Criteria

Male or female participants from 11 years up to 21 years old.

Inclusion Criteria

  • Enrolled health plan members for at least 6 months prior to cohort entry
  • Enrolled between March 1, 2005 and August 31, 2008
  • Birth dates between March 2, 1986 and August 30, 1997 for the primary study cohort
  • Birth dates between March 2, 1983 to March 1, 1986 for the secondary cohort

Exclusion Criteria

    Additional Information

    Official title Risk of Guillain-Barré Syndrome Following Meningococcal Conjugate (MCV4) Vaccination
    Principal investigator Richard Platt, MD, MS
    Description We are conducting a multi-site retrospective study of the relationship between immunization with tetravalent meningococcal conjugate vaccine (MCV4) and Guillain-Barré syndrome (GBS) in adolescents over the 42-month period of March 1, 2005 to August 31, 2008. The study will utilize a hybrid cohort/nested case control design to allow direct calculation of incidence rates of GBS using distributed data processing at the site level, and an efficient pooled multivariate analysis of the time dependent risk of GBS following MCV4 vaccination. The study cohort will be assembled from health plan members enrolled at selected health plans throughout the United States. Cases and matched controls will be identified using administrative data, and case validation and collection of information on predisposing factors prior to GBS onset will be performed by medical record review. A conditional logistic regression model will be used to account for the matching, with days since vaccination with MCV4 the main covariate of interest. As an additional assessment of the primary hypothesis, a case-series analysis using the approach described by Farrington for vaccine safety studies will be performed to account for unmeasured confounders that may be associated with vaccination status.
    Trial information was received from ClinicalTrials.gov and was last updated in December 2007.
    Information provided to ClinicalTrials.gov by Harvard Pilgrim Health Care.