2003-12-31-世界卫生组织-Recommendations_for_the_production_and_control_of_group_C_meningococcal_conjugate_vaccines,_Annex_3,_TRS_No_926_5页_41kb

WHO Recommendations for Group C Meningococcal Conjugate Vaccines Production and Control (Addendum 2003)

The WHO Expert Committee on Biological Standardization adopted recommendations for the production and control of group C meningococcal conjugate vaccines, with an addendum focusing on serological assays to evaluate immune responses based on data from the United Kingdom. These recommendations are for manufacturers and national regulatory authorities to ensure vaccine safety and efficacy.

Key recommendations include:

• Manufacturers must evaluate immunogenicity, including induction of immunological memory, for Single-component or Combined meningococcal C conjugate vaccines in target age groups before licensing.
• National regulatory authorities should use data to inform national immunization programs and ensure no clinically significant interference with vaccine coadministration or mixing.
• Immunogenicity is assessed using the serum bactericidal antibody assay (considered gold standard) and enzyme-linked immunosorbent assay (ELISA). The serum bactericidal assay has a cut-off of titres less than 8 for susceptibility, and imunological memory can be demonstrated through increased titres or avidity indices post-vaccination.
• Long-term protection relies on monitoring immunological memory, as antibody levels decline over time. Vaccines must not interfere with protective immunity from carrier proteins like diphtheria CRM197 or tetanus toxoids.
• Reference standards are available from the National Institute for Biological Standards and Control.

This addendum updates current guidelines based on UK evidence, providing a framework for evaluating vaccine correlates of protection and immune responses.

Authors: Dr R. Borrow, Dr L. Jodar, Dr E. Griffiths.
Acknowledgements: Thanks to Dr I. Feavers, Dr D. Granoff, Dr C. Frasch for comments.
References: Listed in original document.