A Systematic Review of Studies of the Effect of Influenza Vaccine Against Mismatched Strains

This study has been completed.
Information provided by (Responsible Party):
ClinicalTrials.gov Identifier:
First received: August 12, 2011
Last updated: December 13, 2012
Last verified: December 2012

The purpose of this study is to consolidate the cross-protection offered by influenza vaccines against circulating influenza A or B viruses that are not antigenically well-matched to vaccine strains and to determine the degree of cross-protection separately for influenza A and influenza B, through a systematic review of the literature.

Condition Intervention
Biological: Vaccines

Study Type: Observational
Official Title: Effect of Influenza Vaccine Against Mismatched Strains: Systematic Review

Resource links provided by NLM:

Further study details as provided by GlaxoSmithKline:

Primary Outcome Measures:
  • Incidence of laboratory-confirmed influenza [Polymerase Chain Reaction (PCR) or viral culture]. [ Designated as safety issue: No ]

Secondary Outcome Measures:
  • Incidence of laboratory-confirmed influenza through antibody assay (a less sensitive test than PCR or viral culture), alone or combined with PCR, and/or viral culture. [ Designated as safety issue: No ]

Enrollment: 1
Study Start Date: August 2011
Study Completion Date: December 2011
Primary Completion Date: December 2011 (Final data collection date for primary outcome measure)
Groups/Cohorts Assigned Interventions
Cross-Protection Studies
Not applicable.
Biological: Vaccines
Unadjuvanted, monovalent, and trivalent vaccines, and vaccines delivered intramuscularly, intradermally, or intranasally, depending on what is found in the included studies.

Detailed Description:

The research question of this project is: "what is the cross-protection afforded by vaccination (using an LAIV, TIV, or other type of vaccine) against influenza A or B and their subtypes and lineages?" The Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) Statement will be used to guide the reporting of this review. Studies reporting cross-protection data after vaccination with approved formulations of influenza vaccines with influenza A or B will be included. Inclusion will not be limited by publication status, or year of dissemination but will be limited to randomized clinical trials (RCTs) and quasi-RCTs comparing influenza vaccine(s) with placebo. Only RCTs written in English will be included. A meta-analysis will be conducted if there is sufficient data.


Genders Eligible for Study:   Both
Accepts Healthy Volunteers:   Yes
Sampling Method:   Non-Probability Sample
Study Population

Healthy subjects vaccinated with an influenza vaccine.


Inclusion Criteria:

  • Healthy children, adults or the elderly will be included that participated in randomized clinical trials (RCTs) and quasi-RCTs comparing influenza vaccine(s) with placebo.
  • Placebo-controlled randomized clinical trials (RCTs) reporting laboratory-confirmed influenza among healthy participants vaccinated with antigens of influenza strains that differed from those circulating.
  • All influenza vaccines will be included, and will be categorized as TIV, LAIV, and others (that is, non-TIV or non-LAIV).
  • Only RCTs written in English will be included.

Exclusion Criteria:

  • RCTs which are not providing any data will be excluded.
  • Studies using rapid influenza diagnostic tests will not be included, as their sensitivity is low (especially during flu season) and false positives are common during low activity seasons.
  • Laboratory-confirmed influenza through antibody assay as part of the primary outcome will not be included, as this is a less sensitive test than PCR and viral culture.
  Contacts and Locations
Please refer to this study by its ClinicalTrials.gov identifier: NCT01416597

Sponsors and Collaborators
Study Director: GSK Clinical Trials GlaxoSmithKline
  More Information

No publications provided

Responsible Party: GlaxoSmithKline
ClinicalTrials.gov Identifier: NCT01416597     History of Changes
Other Study ID Numbers: 115997
Study First Received: August 12, 2011
Last Updated: December 13, 2012
Health Authority: United States: Food and Drug Administration
Canada: Health Canada

Keywords provided by GlaxoSmithKline:
Systematic review
Mismatched strains

Additional relevant MeSH terms:
Influenza, Human
Orthomyxoviridae Infections
RNA Virus Infections
Virus Diseases
Respiratory Tract Infections
Respiratory Tract Diseases

ClinicalTrials.gov processed this record on April 16, 2014