A brief talk on the GLP vaccine ADME

  • Hepatitis B is a life-threatening liver infection caused by hepatitis B virus. In 2015, about 887,000 people worldwide suffered from post-hepatitis B cirrhosis and liver cancer. Since 1987, Beijing has been vaccinating newborns with hepatitis B vaccine. In 2002, hepatitis B vaccine assessment has been included in the immunization program, and newborns have been vaccinated comprehensively. In 2008, the first-grade students have been vaccinated. According to the results of seroepidemiological survey of hepatitis B organized by Beijing Center for Disease Control in 2005, the prevalence of hepatitis B virus surface antigen (HBsAg) decreased from 5.76% in 1992 to 3.02% among the population aged 1-59 in Beijing, indicating that Beijing is undergoing a transition to a low epidemic area. Vaccination of hepatitis B vaccine requires a huge amount of money every year, so it is necessary to evaluate the health economics of hepatitis B vaccine vaccination and select the most economical and effective vaccination strategy.

     

    People seek vaccines to prevent and control hepatitis B. In the late 1970s, Maupas et al. developed a hematogenous hepatitis B subunit vaccine by extracting HBsAg from the plasma of asymptomatic HBV carrier protein. However, due to the characteristics of low production, high production cost and waste of plasma, the original Ministry of Health of China clearly stipulated that the production of blood-borne hepatitis B vaccine should be stopped from 30 June 1998, and the use of recombinant hepatitis B vaccine should be stopped in 2000. The immune protection effect of recombinant CHO cell hepatitis B vaccine was better than that of recombinant yeast vaccine, and the persistence of large dose recombinant yeast hepatitis B vaccine was better than that of small dose. In 1984, the first generation of hepatitis B blood vaccine was widely used, and was replaced by cell-modified S-yeast hepatitis B vaccine. The wide application of these two vaccines in newborns and children reduced the global chronic carrier rate of hepatitis B virus by 70.00%-90.00%. However, 10.00%-30.00% of HBsAg/HBeAg-positive mothers became chronic carriers because they could not be blocked by vaccination alone. The reason is that all of them. The inhomogeneity of HBsAg subtypes in 99.00% of chronic carriers of the globe; the second generation of hepatitis B vaccine contains partial misfolded HBsAg, lacking of antigenic determinants carrying major binding sites of hepatitis B virus and neutralizing pre-S1 antigen; the third generation of hepatitis B vaccine produced by mammalian cells contains correct folded HBsAg, major binding sites of hepatitis B virus and antigenic determinants neutralizing pre-S1 antigen. Therefore, it can produce protection faster and overcome the defect of non-response of the second-generation hepatitis B vaccine, so as to play the role of blocking mother-to-child transmission of HBV positive mothers to infants. The third generation hepatitis B vaccine produced by mammalian cells, a vaccine company is expensive, but it can solve mother-to-child transmission in high epidemic areas. Only by increasing the vaccination rate of this high-quality vaccine, can it be possible to eliminate hepatitis B.

     

    One of the difficulties in hepatitis B control is that in addition to the widespread promotion of timely vaccination of newborns with hepatitis B vaccine, children under the age of 15 should be revaccinated. Although Brazil began to vaccinate newborns with hepatitis B vaccine in 1998 and expanded to children under 20 years old in 2001, the positive rate of HBV antibodies among children aged 12-20 years was only 56.10% by 2010, and the vaccination rate among children aged 15 years and over was less than 50.00%. In addition, the low timely rate of the first injection for newborns in remote areas is also the difficulty of hepatitis B prevention. The hospital delivery rates of puerperal in two counties of Yunnan in 1995-1999 and 2000 were 43.77% and 51.63% respectively. In 1995-1999 and 2000, the timely vaccination rates of the first hepatitis B vaccine for children born within 48 hours after birth were 1.69% and 31.48%, respectively, for newborns, 3.74% and 46.07%, and 30.43% and 79.65% for the whole course of three hepatitis B vaccines, respectively. After the implementation of the poverty alleviation project of hepatitis B vaccine, the timely vaccination rates of the first hepatitis B vaccine for children born in 2000 in the two counties were also only scored. 38.55% and 25.00% respectively. This shows that how to improve the timely rate of the first injection for newborns born at home is an urgent need for innovative measures to prevent hepatitis B.

     

    So far, there has been no research and evaluation on the social and economic benefits of hepatitis B vaccination for all newborns in the whole province for 22 years. The long-term vaccination work in Guangxi for 22 years is not only a measure with domestic characteristics but also in line with foreign innovations. It is of great significance to study and evaluate the social and economic benefits of hepatitis B vaccination for newborns in the whole region.

     

    For more information about the GLP vaccine ADME,  you can visit our website by clicking the links in the article.