Potency Test of Human Hepatitis B Immunoglobulin in Thailand

Abstract

Background: The prevention or treatment for people without immunity who were close-contacted with hepatitis B infection is to apply human hepatitis B immunoglobulin (HBIG) immediately together with hepatitis B vaccine. The potency of human hepatitis B immunoglobulin expresses their competency to bind to Hepatitis B surface antigens.  At present, there are five product brands that were approved by the Thai Food and Drug Administration. Three brands are distributed in Thailand, one is produced in the country and the other two are imported. Each manufacturer company uses different immunoassay methods to test the potency of HBIG according to European pharmacopoeia 9.0, whereas the Institute of Biological Products has no method of HBIG potency testing. Hence, study must be conducted for the potency test of HBIG products to be used as a standard method of testing products distributed in the country. 

Objective: To prove that the testing method is suitable and can be used as a standard method for potency test on all HBIG products that are distributed in Thailand.

Methodology: This study selected a commercial test kits for quantitative determination of anti-HBs in serum or plasma with Enzyme-Linked Immunosorbent Assay (ELISA) technique which is validated by international standard. Then, the research used it to examine the potency of HBIG products that distributed in the country between 2016 and 2019 in using samples from three product brands including 15 lots of the production and compare the results with the test results of the manufacturers to prove that it can be used as a standard method.

Results: Using the commercial test kit to examine antibody to hepatitis B virus in serum or plasma of patients to test the potency by ELISA method in 15 lots of 3 product brands found that the test results were similar to those of the manufacturers; there were not statistically significant difference (p>0.05). The results met the requirements of the European Pharmacopeia 9.0 and specification of each licensed products in the country. The application of the commercial test kit can reduce the test preparation period and decrease a variation of substance providing. Moreover, using international standard substance reference on the World Health Organization and use the same dilution method as the samples yielded the test results more reliable.

Conclusions: The results indicate that the commercial test kit is suitable and able to be use as a standard method for potency determination in all products that distributed in Thailand.