Collaborative calibration of the 9th national standard for human rabies vaccine / 中国生物制品学杂志

@#Objective To collaboratively calibrate and finally assign the potency of the 9th national standard for human rabies vaccine for candidate.Methods Qualified laboratories for the production,research and development of human rabies vaccines were organized to determine the potency of candidate national standard for rabies vaccines by using NIH method,with the 7th international standard for rabies vaccines(NIBSC code:16/204)as the reference standard. The detection results were statistically analyzed,and the geometric mean of effective detection values was taken as the final potency value of the candidate standard. According to the requirements of the preparation of national drug reference materials,the candidate standard was destroyed by heat acceleration,and then detected for the glycoprotein antigen to investigate the stability.Results A total of 20 laboratories participated in the collaborative calibration,of which the two laboratories that did not strictly follow the collaborative calibration SOP were excluded,and the data of the remaining collaborative laboratories were valid. After statistical analysis,the final potency of the 9th national standard for rabies vaccine was 11. 4 IU/mL,the 95% confidence limit was 10. 9～11. 9 IU/mL,and the 95% reference range of ED_(50) was 2. 10～2. 75. There was no significant difference in the results of glycoprotein antigen detection under different time conditions(2,4,8 and 16 weeks)at 37 ℃.Conclusion The collaborative calibration research of the 9th national standard for human rabies vaccine(batch number:201906001)has been completed,the potency assignment is scientific and rigorous,the data was reliable,and the thermal stability meets the requirements. At present,this standard has been approved by the National Drug Reference Material Committee,which is of great significance to the quality control of human rabies vaccine,especially the quality control of effectiveness.

Reflections on national reference materials of preventive human vaccines / 中国生物制品学杂志

@#The national standards for biological products include three types of reference materials,vaccines,biotherapeutics,and diagnostics,among which the national standards for vaccines play a crucial role in the production,issuance,and supervision inspection of vaccines. In recent years,the vaccine industry in China has developed rapidly,and especially,the application of new technology platforms such as mRNA in vaccines has highlighted the urgency of further improving the level of national standards for vaccines in China. Referring to WHO(World Health Organization)development requirements for reference materials of vaccines and taking Chinese national standard for SARS-CoV-2 neutralizing antibody as example,this paper summarized the thinking on national standards for vaccines in China,and presented the priority principles of establishing national standards for vaccines which are not traceable to WHO international standard(IS),in view to provide ideas for the further improvement of development and application of national standards for vaccines in China.

Development of national standards for genomic titer determination of recombinant type 5 adeno-associated virus / 中国生物制品学杂志

@#ObjectiveTo develop a national standard for genomic titer determination of recombinant type 5 adeno-associated virus(rAAV5).MethodsThe rAAV5-GFP stock solution prepared by the three-plasmid system was identified and verified for the appearance,pH,sterility,genomic titer,purity and infection titer according to the relevant requirements of Chinese Pharmacopoeia(Volume Ⅲ,2020 edition),which was diluted and subpackaged to prepare candidate standards according to the results;The stability of candidate standards was investigated by thermal acceleration test;Three laboratories were organized to collaboratively calibrate the candidate standards using droplet digital PCR(ddPCR).ResultsAll the detection indexes of the candidate standard and the stock solution met the relevant requirements;The genomic titer showed no significant decrease at 25,4,-20,-40,-80 ℃ for 1,3,4,6 months;Through collaborative calibration by three laboratories,the candidate standard was assigned a value of 2. 56 × 10(12)copies/mL,and the 95% confidence interval was 2. 48 ×10(12)copies/mL,and the 95% confidence interval was 2. 48 ×10(12)copies/mL ～ 2. 64 × 10(12)copies/mL ～ 2. 64 × 10(12)copies/mL.ConclusionThe developed national standard for the determination of rAAV5 genomic titer had good stability and might be used for the quality evaluation of rAAV5 related products.

Development of bacterial endotoxin standard for insoluble samples / 中国药理学通报

Aim To establish a batch of endotoxin standard for baeterial endotoxin detection of insoluble samples.Methods Candidate A and candidate B were prepared by freeze -drying bacterial endotoxin without excipient.The two batches of candidates were calibrated by three methods, including 13 laboratories for gel method, 9 laboratories for kinetic-turbidimetric assay and 5 laboratories for kinetic chromogenic assay.Results After statistical analysis, the geometric mean values of gel method, kinetic-turbidimetric assay and kinetic chromogenic assay calibration of candidate A were 680.1 EU, 827.0 EU and 800.8 EU, with RSD of 22.4%, 16.2% and 16.7%, respectively.The P value of variance analysis of calibration results of the three methods was 0.067, showing no significant difference.The weighted mean of potency was 774.0 EU (95% confidence interval 721.0 - 831.0, FL% 7.10).The geometric mean values of the calibration of candidate B by gel method, kinetic-turbidimetric assay and kinetic chromogenic assay method were 1 640.6 EU, 1 828.6 EU and 3 224.8 EU, with RSD of 33.9% , 47.0% and 54.4% , respectively.The P val¬ue of variance analysis of the calibration results of the three methods was 0.030, showing significant differ¬ence.Chi-square test was used to correct the weight of each method , and weighted average of the results of the three methods was used to obtain a corrected weighted average efficiency value of 1 822.7 EU (95% confi¬dence interval 1 548.7 -2 145.2, FL% 16.4).Can¬didate B was eliminated based on the results.Conclu¬sion Candidate A has become the first batch of na¬tional standard bacterial endotoxin (for insoluble sam¬ples only) approved by National Standard Substance Committee of China, and the potency is 700 EU.

Development of a reference substance for live bacterial count of Streptococcicosis live vaccines / 生物工程学报

This study attempts to develop a reference substance for the live bacteria count of Streptococcicosis live vaccines in order to evaluate the validity of live bacterial count in inspection and testing. We prepared a batch of live Streptococcus suis reference substance for live bacterial count, tested their physical property, purity, vacuum degree, remaining moisture, and determined their homogeneity, thermal stability and transportation stability. Moreover, we organized collaborative calibration to assign count values to the reference substance and determine the shelf life of the reference substance in 12 months. The results showed that the physical property, the purity, the remaining moisture and the vacuum degree of the reference substance were all in compliance with the requirements of the Chinese Veterinary Pharmacopoeia. The homogeneity test showed that the coefficient of variation of the count of the reference substance was less than 10%, indicating a good homogeneity. Transportation stability test showed that the reference substance remained active after 72 h transportation in summer and winter with the package of styrofoam boxes and ice packs. Thermal stability test showed that the reference substance could be stored for up to 3 months at -20 °C, or up to 21 days at 4 °C. According to the collaborative calibration, the reference vaccine was assigned a count value range of (8.5-12.1)×107 CFU/ampoule. The shelf life test showed that the reference substance was stable for 12 months when stored at -70 °C. The reference substance could provide a reference for the live bacterial count of Streptococcicosis live vaccines. Moreover, it could also be used as a reference to evaluate the quality of corresponding agar media.