Clinical evaluation of influenza vaccines
Table for pandemic and potentially pandemic influenza vaccines
Table for seasonal influenza vaccines
NB: When opening attached abstracts from the Excel table - users may receive an anti-virus warning. Please be assured the attached files are safe for download and the warning is generated by MS Office being cautious.
Information about immunogenicity, as well as efficacy or effectiveness (when available) of human influenza vaccines is presented on two separate tables for pandemic/”pre-pandemic” and seasonal vaccines. Both sets of data include interventional and observational studies.
The table on pandemic/”pre-pandemic” vaccines, compiled by WHO starting in 2007 upon request of its Member States and of various stakeholders in the area of pandemic preparedness, provides an abbreviated description of data provided in preliminary form to WHO on the status of recent development of vaccines directed against influenza strains with pandemic potential.
The table on seasonal vaccines was prepared for the first time in 2012 to summarise data on safety , immunogenicity and efficacy/effectiveness in humans, including in high risk groups. Manufacturers from several countries have reported to WHO their work to assess in clinical trials the seasonal vaccines administrated by alternative ways or developed using new biotechnological approaches. Recently, the first quadrivalent live attenuated vaccine influenza vaccine was licenced in one country after a number of successful clinical trials.
Because of inherent variability in the hemagglutination inhibition and neutralization antibody assay systems used to measure immunogenicity, and the lack of standardized methods for these assays , it is unwise to attempt to make direct comparisons of results from different clinical trials. Moreover, data presented was in some cases obtained in small groups of volunteers.
This table was developed using data from:
- IFPMA, http://clinicaltrials.ifpma.org/clinicaltrials/no_cache/en/myportal/index.htm
- International Clinical Trials Registry Platform (ICTRP), http://www.who.int/ictrp/en/
- ClinicalTrials.gov, http://clinicaltrials.gov/ct2/search
Other sources of the information include materials presented at technical meetings convened by WHO, publications and direct contacts with manufacturers and investigators in charge of clinical trials. Upon specific request of clinical investigators or manufacturers, some data has not been included in the table, as indicated by the mention (No data).
The current version of the Tables is proposed as an Excel document. This allows users to filter (using a drop down menu) the data for the following variables:
- Type of vaccine
- Subtype of influenza virus
- Strain of influenza virus
- Substrate for production
- Adjuvant used
- Clinical development phase
- Number of subjects
- Route of administration of the vaccine
Both tables are revised periodically. WHO also calls on those who have not participated in its previous consultations to make available information on planned on going vaccine trials for inclusion into the Tables.
The Government of Canada is thanked for generous support to the initiation of this work.