EVALUATION OF THE STABILITY OF NATIONAL STANDARDS FOR THE INACTIVATED POLIO VACCINE

Abstract

Background/Purpose: A national standard for inactivated polio vaccine (IPV) was established for the quality assurance of vaccines. Based on the demand for vaccine quality management, the number of national standard vaccines must be in large quantities and the quality should be stable for a long time (10 years or more). Producing standard vaccines is divided into 2 main contents. The first is to establish and evaluate the national reference standards, the second is to evaluate the stability of the product. Therefore, determining the stability of the vaccine is extremely important and accounts for most of the work in establishing the national standard vaccine. NICVB has successfully established the prescribed number of standard IPV vaccines. In this study, we present the process of studying the stability of the standard IPV.

Methods: A lot of standard vaccines manufactured by POLYVAC were used to establish the standard for the national standard. ELISA analysis was used to evaluate the antigen content of the candidate standard and in the thermo-stability study with storage temperature and time following the guidelines of the World Health Organization (4^oC, 25^oC, 37^oC for different time periods: 1 week, 2 weeks, and 4 weeks for type 1, 2, and 3. Data were analyzed by the Arrhenius equation to calculate the shelf life of standard IPV vaccines.

Results: The results show the national standard vaccine batch MCQG.IPV-01 with the number of 1500 vials met the requirements for thermal stability for all 3 serotypes 1, 2, 3, and the shelf life is up to 10 years.

Conclusion: The national standard IPV, after meeting research criteria, is put into use with the stability of standard type 1: 6,239 (95% CI: 5,326 - 7,151) DU/ml, type 2: 10,737 (95% CI: 9,504 – 11,970) DU/ml, type 3: 17.438 (95% CI: 15.365 – 19,511) DU/ml when stored at -70^oC.