key: cord-0877827-2bzq2ayq authors: Edara, V. V.; Patel, M.; Suthar, M. S. title: Covaxin (BBV152) Vaccine Neutralizes SARS-CoV-2 Delta and Omicron variants date: 2022-01-28 journal: nan DOI: 10.1101/2022.01.24.22269189 sha: 0e3b10c6ef4b8263ca6fd8a3dd0d64fcf7eaf15f doc_id: 877827 cord_uid: 2bzq2ayq The SARS-CoV-2 vaccine BBV152/Covaxin is well-tolerated and was shown to be 77.8% efficacious against symptomatic and 93.4% efficacious against severe symptomatic COVID-19 disease in adults. Previous studies have shown that sera from Covaxin vaccinated individuals have neutralizing activity against B.1.1.7 (Alpha), B.1.351 (Beta), B.1.617.2 (Delta), B.1.1.28 (Zeta), and B.1.617.1 (Kappa) SARS-CoV-2 variants. The B.1.1.529 variant (Omicron) recently emerged in November 2021 and has spread throughout the world. The Omicron variant has more than 30 mutations within the spike protein that could impact vaccine-mediated immunity. We used a live virus neutralization assay to evaluate the neutralizing activity against the Omicron variant of sera collected from subjects who received a booster dose (6- month after primary series last dose) of Covaxin. We found that sera from Covaxin boosted individuals showed neutralizing activity against D614G (vaccine strain), Delta, and Omicron variants. One hundred percent of boosted subjects showed neutralizing activity against the Delta variant while over 90% of boosted subjects showed neutralizing activity against the Omicron variant. These findings show that a booster dose of Covaxin can generate robust neutralizing antibody responses against the Omicron variant. All rights reserved. No reuse allowed without permission. (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. The copyright holder for this preprint this version posted January 28, 2022. ; https://doi.org/10.1101/2022.01.24.22269189 doi: medRxiv preprint NOTE: This preprint reports new research that has not been certified by peer review and should not be used to guide clinical practice. The SARS-CoV-2 vaccine BBV152/Covaxin is well-tolerated and was shown to be 77. 8% (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. The copyright holder for this preprint this version posted January 28, 2022. In an ongoing phase 2 trial (ClinicalTrials.gov: NCT04471519) the protocol was amended after 65 six months to re-consent and randomize previously vaccinated participants to receive a third dose 66 (booster) of Covaxin on Day 215. 9 Sera were collected 28 days after booster and used in 67 neutralization assay in this study. Sera from booster study was effective in neutralizing the D614G 68 All rights reserved. No reuse allowed without permission. (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. The copyright holder for this preprint this version posted January 28, 2022. (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. The copyright holder for this preprint this version posted January 28, 2022. ; https://doi.org/10.1101/2022.01.24.22269189 doi: medRxiv preprint (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. All rights reserved. No reuse allowed without permission. (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. The copyright holder for this preprint this version posted January 28, 2022. ; https://doi.org/10.1101/2022.01.24.22269189 doi: medRxiv preprint Methods Viruses and cells. VeroE6-TMPRSS2 cells were generated and cultured as previously described. 11 VeroE6-TMPRSS2 cells were used to propagate all virus stocks. The D614G, B.1.617.2, and B.1.1.529 viruses were isolated and propagated on Vero-TMPRSS2 cells as previously described. [10] [11] [12] All the variants were plaque purified directly from the nasal swabs, propagated once in a 12-well plate, and expanded in a confluent T175 flasks to generate working stocks. All viruses used in this study were deep sequenced and confirmed as previously described. 11 Samples. Collection and processing were performed by Bharat Biotech India Limited. These samples were collected from booster study. In the ongoing phase 2 trial (ClinicalTrials.gov: NCT04471519) the protocol was amended after six months to re-consent and randomize previously vaccinated participants to receive a third dose (booster) of Covaxin on Day 215. Sera were collected 28 days after booster and used in neutralization assay in this study. 9 Focus Reduction Neutralization Test. FRNT assays were performed as previously described. 11, 13, 14 Briefly, samples were diluted at 3-fold in 8 serial dilutions using DMEM in duplicates with an initial dilution of 1:10 in a total volume of 60 µL. Serially diluted samples were (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. The copyright holder for this preprint this version posted January 28, 2022. ; https://doi.org/10.1101/2022.01.24.22269189 doi: medRxiv preprint CoV spike primary antibody directly conjugated to Alexa-flour-647 (CR3022-AF647) overnight at 4°C. Cells were washed three times in PBS and foci were visualized on a CTL Analyzer. Quantification and Statistical Analysis. Antibody neutralization was quantified by counting the number of foci for each sample using the Viridot. 15 The neutralization titers were calculated as follows: 1 -(ratio of the mean number of foci in the presence of sera and foci at the highest dilution of respective sera sample). Each specimen was tested in duplicate. The FRNT50 titers were interpolated using a 4-parameter nonlinear regression in GraphPad Prism 9.2.0. Samples that do not neutralize at the limit of detection at 50% are plotted at 10 and were used for geometric mean and fold-change calculations. All rights reserved. No reuse allowed without permission. (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. The copyright holder for this preprint this version posted January 28, 2022. ; https://doi.org/10.1101/2022.01.24.22269189 doi: medRxiv preprint Efficacy, safety, and lot-to-lot immunogenicity of an inactivated SARS-CoV-2 vaccine (BBV152): interim results of a randomised, double-blind, controlled, phase 3 trial Severe breakthrough COVID-19 cases in the SARS-CoV-2 delta (B.1.617.2) variant era Protection and waning of natural and hybrid COVID-19 immunity. medRxiv CDC. COVID-19 Vaccines Work Inactivated COVID-19 vaccine BBV152/COVAXIN effectively neutralizes recently emerged B.1.1.7 variant of SARS-CoV-2 Neutralization of VUI B.1.1.28 P2 variant with sera of COVID-19 recovered cases and recipients of Covaxin an inactivated COVID-19 vaccine Neutralization of variant under investigation B.1.617 with sera of BBV152 vaccinees Neutralization of Beta and Delta variant with sera of COVID-19 recovered cases and vaccinees of inactivated COVID-19 vaccine BBV152/Covaxin Persistence of immunity and impact of a third (booster) dose of an inactivated SARS-CoV-2 vaccine, BBV152; a phase 2, double-blind, randomised controlled trial. medRxiv mRNA-1273 and BNT162b2 mRNA vaccines have reduced neutralizing activity against the SARS-CoV-2 Omicron variant. bioRxiv Infection and Vaccine-Induced Neutralizing-Antibody Responses to the SARS-CoV-2 B.1.617 Variants Neutralizing Antibodies Against SARS-CoV-2 Variants After Infection and Vaccination Development of a Rapid Focus Reduction Neutralization Test Assay for Measuring SARS-CoV-2 Neutralizing Antibodies Infection-and vaccine-induced antibody binding and neutralization of the B.1.351 SARS-CoV-2 variant Viridot: An automated virus plaque (immunofocus) counter for the measurement of serological neutralizing responses with application to dengue virus This work was sponsored by Ocugen, Inc., Malvern, USA, and serum samples were provided by Bharat Biotech India Limited, Hyderabad, India. M.S.S has an advisory role with Ocugen and Moderna. All rights reserved. No reuse allowed without permission.(which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity.The copyright holder for this preprint this version posted January 28, 2022. ; https://doi.org/10.1101/2022.01.24.22269189 doi: medRxiv preprint