key: cord-0327878-dxym95pe authors: Sinto, R.; Utomo, D.; Suwarti, S.; Nelwan, E. J.; Surendra, H.; Natasha, C.; Fransiska, F.; Theresia, D.; Ranitria, A. F.; Subekti, D.; Nuraeni, N.; Handayani, W.; Rahardjani, M.; Baird, J. K.; Dunachie, S.; Shankar, A. H.; Hamers, R. L. title: Serum anti-Spike antibody titers before and after heterologous booster with mRNA-1273 SARS-CoV-2 vaccine following two doses of inactivated whole-virus CoronaVac vaccine date: 2021-12-24 journal: nan DOI: 10.1101/2021.12.24.21268360 sha: fe53f439d004f6c01a55e69b7c4885bc6934997e doc_id: 327878 cord_uid: dxym95pe Background: The inactivated whole-virus vaccine CoronaVac (SinoVac) is the COVID-19 vaccine most administered worldwide. However, data on its immunogenicity and reactogenicity to heterologous boosting with mRNA vaccines are lacking. Methods: In a cohort of hospital staff in Jakarta, Indonesia, who received two-dose CoronaVac six months prior (median 190 days, IQR165-232), we measured anti-Spike IgG titers on paired serum samples taken before and 28 days after a 100g mRNA-1273 (Moderna) booster. We performed correlations and multivariable ordinal regressions. Findings: Among 304 participants, the median age was 31 years (range 21-59), 235 (77.3%) were women, 197 (64.8%) had one or more previous SARS-CoV-2 infections (including 155 [51.0%] who had a post-CoronaVac breakthrough infection. Pre-boost IgG titers correlated negatively with the time since the latest documented virus exposure (either by the second CoronaVac or SARS-CoV-2-infection whichever most recent). Previous SARS-CoV-2 infection and a longer time interval between second vaccine and mRNA-1273 boost were associated with a higher pre-boost IgG titer. Post-booster, the median IgG titer increased 9.3-fold, from 250 (IQR32-1389) to 2313 (IQR1226-4324) binding antibody units (BAU/mL) (p<0.001). All participants, including seven whose pre-boost IgG was below assay detection limits, became seropositive and all reached a substantial post-boost titer ([≥]364 BAU/mL). Post-boost IgG was not associated with pre-boost titer or previous SARS-CoV-2 infection. Booster reactogenicity was acceptable, with 7.9% of participants experiencing short-lived impairment of activities of daily living (ADL). Interpretation: A heterologous, high-dose mRNA-1273 booster after two-dose CoronaVac was highly immunogenic and safe, including in those most in need of improved immunity. Funding: Wellcome Trust, UK Keywords SARS-CoV-2; COVID-19; inactivated vaccine; CoronaVac; mRNA-1273; antibodies Evidence before this study The inactivated whole-virus vaccine CoronaVac (SinoVac) is the COVID-19 vaccine most administered worldwide, at around 2 billion doses in 54 countries. Concerns that CoronaVac has lower immunogenicity than virus vector or mRNA vaccines, with pronounced decreases of neutralising antibody titres within a few months, and reduced effectiveness in the older population, highlight the urgent need for immunogenic, safe and well-tolerated booster schedules, especially with Omicron rapidly emerging. We used the terms "SARS-CoV-2", "COVID-19", "vaccine", "booster" to search PubMed and medRxiv up to Dec 22th, 2021, with no language or date restrictions, to identify clinical trials and real-world studies reporting on the immune responses and reactogenicity to a "third booster" of currently approved COVID-19 vaccines. Previous research reported that neutralising antibody responses elicited by all currently approved vaccines (mRNA, adenovirus-vectored, inactivated, and protein subunit) declined to varying degrees after 6-8 months after full-schedule vaccination. Several clinical trials have evaluated heterologous ("mix and match") vaccination schedules, demonstrating robust immune responses in adults. After two-dose CoronaVac, BNT162b2 (Pfizer-BioNTech) boost was significantly more immunogenic than a homologous booster against wild-type and Variants of Concern (VOCs) Beta, Gamma and Delta, and AZD1222 boost increased spike RBD-specific IgG 9-10-fold, with high neutralizing activity against the wild type and VOCs. Compared to previous SARS-CoV-2 variants, current vaccine boosters appeared to neutralise Delta to a slightly lesser degree, and Omicron to a substantially lesser degree, although preliminary data from Moderna found that the authorised dose (50g) of the mRNA-1273 boost increased antibodies 37-fold and the high-dose (100g) boost 83-fold. is the author/funder, who has granted medRxiv a license to display the preprint in (which was not certified by peer review) preprint The copyright holder for this this version posted December 24, 2021. ; https://doi.org/10.1101/2021.12.24.21268360 doi: medRxiv preprint To our knowledge, this study is the first to provide critical real-world evidence that heterologous boosting with high-dose mRNA-1273 vaccine after CoronaVac is highly immunogenic, safe and well-tolerated in adults. After a primary course of two-dose CoronaVac, we found that a high-dose (100g) mRNA-1273 booster was immunogenic for all participants in a highly exposed cohort of hospital staff in Jakarta, Indonesia, in the context of Delta predominance, particularly for those with the lowest pre-boost antibody levels. All participants became seropositive and all reached a substantial post-boost titer (364 BAU/mL), up to a median 9.3-fold increase. Booster reactogenicity was acceptable, with 7.9% of participants experiencing short-lived impairment of activities of daily living The study findings contribute to informing policy makers on flexible options in deploying COVID-19 vaccines in mix-and-match schedules, with particular relevance for countries that are largely dependent on inactivated vaccines. Further trials are warranted that assess clinical endpoints of optimized doses of mRNA-1273 booster, and variant-specific or multivalent vaccines in response to decreased protection against emerging SARS-CoV-2 VOCs. Vaccine-induced population immunity is a key global strategy to control the COVID-19 pandemic, and to date eight COVID-19 vaccines have received Emergency Use Listing (EUL) by the WHO 1 . Although most studies suggest well preserved protection against severe COVID-19 disease and death, including against variants such as the Delta (B.1.617.2) strain, accumulating evidence shows a progressive decline in protection after a two-dose vaccine schedule in preventing breakthrough infections associated with diminishing humoral immunity over time [2] [3] [4] [5] . In addition, neutralisation and vaccine effectiveness after two-dose vaccine schedules are greatly reduced for the recently emerged Omicron variant (B.1.1.529) 6 , with significant restoration after a third "booster dose" of an mRNA vaccine 7 . Recent trials suggested that heterologous (or "mix and match") virus-vectored or mRNA booster strategies were more immunogenic than a homologous schedule [8] [9] [10] [11] [12] , albeit with increased reactogenicity in some combinations 13 However, recent studies reported CoronaVac to have lower immunogenicity than virus vector or mRNA vaccines 18, 19 , and a pronounced decrease of neutralising antibody titres within a few months [19] [20] [21] , and reduced effectiveness in the elderly 22, 23 . This lack of protection is concerning, especially given the rapid emergence of Omicron 6 . is the author/funder, who has granted medRxiv a license to display the preprint in (which was not certified by peer review) preprint Given the dearth of data on effectiveness, immunity and reactogenicity of a heterologous booster dose for inactivated whole-virus COVID-19 vaccines 18,26 , we investigated the immunogenicity and reactogenicity of a high-dose (100g) heterologous mRNA-1273 booster given six months after two-dose CoronaVac to heavily SARS-CoV-2 exposed hospital staff, measuring anti-spike (anti-S) IgG antibody titers before and one month after the booster, and the occurrence and severity of adverse events within seven days. The is the author/funder, who has granted medRxiv a license to display the preprint in (which was not certified by peer review) preprint The copyright holder for this this version posted December 24, 2021. ; https://doi.org/10.1101/2021.12.24.21268360 doi: medRxiv preprint Basic demographic and clinical data were captured on an online case report form. Solicited signs of local or systemic reactogenicity during the seven days following the booster dose were recorded in a daily patient diary, and, after study physician verification, were graded for severity (mild, moderate, severe, or disrupting activities of daily living [ADL]). Past COVID-19 was defined as a previously documented PCR-confirmed SARS-CoV-2 infection. Venous blood samples were drawn on the day of the booster dose (between August 5 th , and October 15 th , 2021) and 28 days (allowed window +10 days) thereafter (between September 13 th and November 12 th , 2021). Serum was stored at -80C and transferred to a commercial laboratory, where titers of IgG antibodies against the SARS-CoV-2 spike receptor-binding domain were determined using the chemiluminescent microparticle immunoassay (CMIA) SARS-CoV-2 IgG II Quant assay (Abbott Laboratories, Abbott Park, IL, US) on the Architect i2000sr platform, in accordance with the manufacturer's package insert. Samples with results above the upper limit of quantification were tested again after dilution. The strength of the response (in relative light units) was determined relative to an IgG concurrent calibrator, and reflects the quantity of IgG antibodies present. We expressed test results in WHO International Standard binding antibody units (BAU)/mL using the manufacturer's conversion factor (1 BAU/mL = 0.142 x arbitray units[AU]/mL) 27 . Seropositivity was defined as ≥7.1 BAU/mL. Paired comparisons of IgG titers before and after mRNA-1273 booster dose were performed using the Wilcoxon matched pairs signed-rank test. Correlations of log10 IgG titers were expressed using Spearman coefficient (rs). Multivariable ordinal (proportional odds) logistic regression was performed to assess factors associated with pre-and post-boost log10transformed IgG titer (caterogised in quartiles). Multivariable logistic regression was performed to assess factors associated with occurrence of any severe or disrupting adverse . CC-BY-NC-ND 4.0 International license It is made available under a perpetuity. is the author/funder, who has granted medRxiv a license to display the preprint in (which was not certified by peer review) preprint The funder of the study had no role in study design, data collection, data analysis, data interpretation, or writing of the report. The corresponding author had full access to the study data. There were 304 (86.1%) of 353 cohort participants with complete pre-and post-booster sample pairs, who were included in the analysis. The median age was 31 years (IQR, 27-44, range 21-59), 235 (77.3%) were women, and 28 (9.2%) had one or more comorbidities, including obesity, cardiovascular disease, diabetes mellitus, and asthma ( is the author/funder, who has granted medRxiv a license to display the preprint in (which was not certified by peer review) preprint Pre-boost IgG titers varied from 0.97 BAU/mL to 21 466 BAU/mL (4.35 log10 range), and were higher overall in previously infected than in naïve participants (Figure 1 and Figure S1 ). Preboost IgG titers correlated negatively with the time since the most recent documented "virus . CC-BY-NC-ND 4.0 International license It is made available under a perpetuity. is the author/funder, who has granted medRxiv a license to display the preprint in (which was not certified by peer review) preprint The copyright holder for this this version posted December 24, 2021. ; https://doi.org/10.1101/2021.12.24.21268360 doi: medRxiv preprint exposure", either by the second CoronaVac or SARS-CoV-2 infection (whichever most recent). Participants with a breakthrough infection after post-Coronavac had the shortest time since most recent "virus exposure", and had a higher pre-boost IgG titer than those infected before CoronaVac and naïve participants. Participants with a breakthrough infection post-CoronaVac had the shortest time since most recent "virus exposure" and a higher pre-boost IgG titer than the naïve participants. Pre-boost titers were higher overall in previously infected than in naïve participants. Pre-boost IgG titers correlated negatively with the time since the most recent documented "virus exposure" (either by the second CoronaVac dose or SARS-CoV-2 infection whichever most recent). Participants with a breakthrough infection post-Coronavac had the shortest time since most recent "virus exposure", and had a higher pre-boost IgG titer than those infected before Coronavac and naïve participants. is the author/funder, who has granted medRxiv a license to display the preprint in (which was not certified by peer review) preprint The copyright holder for this this version posted December 24, 2021. ; https://doi.org/10.1101/2021.12.24.21268360 doi: medRxiv preprint All participants reached a substantial post-boost titer, ranging between 364 and 195 452 BAU/mL (2.73 log10 range), and this was irrespective of the pre-boost IgG titer, previous infection, or the timing of the previous infection (either before or after two-dose CoronaVac vaccination). Participants with a breakthrough infection after two-dose CoronaVac had a higher pre-boost IgG titer than those infected before Coronavac and the naïve participants. Post-boost IgG titers were in the same range for all three subgroups (Figure 3) . Post-boost IgG titers did not differ for previous SARS-CoV-2 infection, age, sex, and presence of any comorbidity (Figure S1 and S2) . All participants reached a substantial post-boost titer, ranging between 2570 and 1,380,384 BAU/mL (2.73 log10 range), and this was irrespective of the pre-boost IgG titer, previous infection, or the timing of the previous infection (before or after two-dose CoronaVac vaccination). Participants with a breakthrough infection post-CoronaVac had a higher pre-boost IgG titer than those infected before Coronavac and the naïve participants. Post-boost IgG titers were in the same range for all 3 subgroups. is the author/funder, who has granted medRxiv a license to display the preprint in (which was not certified by peer review) preprint is the author/funder, who has granted medRxiv a license to display the preprint in (which was not certified by peer review) preprint The copyright holder for this this version posted December 24, 2021. ; https://doi.org/10.1101/2021.12.24.21268360 doi: medRxiv preprint In multivariable analysis, previous SARS-CoV-2 infection either before or after two-dose CoronaVac, and a longer time interval between second and mRNA-1273 boost dose were associated with a higher pre-boost IgG titer (p<0.0001 each); age, sex, comorbidity, time interval between first and second dose were not associated. None of these factors, including pre-boost IgG titer, were associated with a higher post-booster IgG titer ( Table 2) . The 304 participants reported a total of 300 adverse reactions within 7 days after mRNA-1273 booster. The percentage of participants with any solicited adverse reaction was 98.7% (300), 96.4% (293) for any local reaction (injection site pain and swelling most frequent) and 90.8% is the author/funder, who has granted medRxiv a license to display the preprint in (which was not certified by peer review) preprint The bar chart shows solicited adverse reactions, that were verified and graded for severity by the study physician. Severity grading: 1) mild (does nor or minimally interfere with usual social and functional activities); 2) moderate (interferes with usual social and functional activities); 3) severe (causing inability to perform usual social and functional activities); 4) disrupting/impairing activities of daily living (ADL). No participants required hospitalization or died. is the author/funder, who has granted medRxiv a license to display the preprint in (which was not certified by peer review) preprint The copyright holder for this this version posted December 24, 2021. ; https://doi.org/10.1101/2021.12.24.21268360 doi: medRxiv preprint is the author/funder, who has granted medRxiv a license to display the preprint in (which was not certified by peer review) preprint The copyright holder for this this version posted December 24, 2021. ; https://doi.org/10.1101/2021. 12.24.21268360 doi: medRxiv preprint Emerging evidence for currently available vaccines suggests that heterologous boosting improves the breadth of humoral and cellular protection more than homologous boosting 11, 12 . A small randomized trial in Hong Kong in adults who had received two-dose CoronaVac with low antibody response, found that an additional heterologous mRNA vaccine booster dose of BNT162b2 (Pfizer-BioNTech) was significantly more immunogenic than a homologous booster dose of CoronaVac booster against wild-type and VOCs 18 . Another study in heath care workers in Thailand who received two-dose CoronaVac found that a heterologous virusvector booster AZD1222 (AstaZeneca) increased spike RBD-specific IgG 9-10-fold, with high neutralizing activity against the wild type and VOCs 26 . Policy makers in several countries have started implementing third or periodic boosting to protect the most vulnerable populations, and mitigate health care and economic impacts. Real-world data and cohort studies are critical to guide decisions regarding when, which populations and what boosters should be administered. Compared to previous SARS-CoV-2 variants, current vaccine boosters appeared to neutralise Delta to a slightly lesser degree 12 , and Omicron to a substantially lesser degree 7 . Nonetheless, on 12 th December, Moderna announced preliminary data that the authorised booster dose of 50g mRNA-1273 increased neutralising antibodies 37-fold and the high-dose of 100g 83-fold, compared to pre-boost levels 29 . Further trials on clinical endpoints of optimized booster doses and variant-specific or multivalent vaccines in response to decreased susceptibility to neutralization of emerging SARS-CoV-2 VOCs are urgently needed 30 . There are some limitations to our study. First, although accumulating evidence suggests that anti-Spike IgG response is a correlate of disease protection 31, 32 , it is important to recognise there is not yet an established or well defined correlate of long-term vaccine protection. In this study we did not assess anti-N IgG, neutralizing antibody or cellular immunity 33 is the author/funder, who has granted medRxiv a license to display the preprint in (which was not certified by peer review) preprint The copyright holder for this this version posted December 24, 2021. ; https://doi.org/10.1101/2021.12.24.21268360 doi: medRxiv preprint not fully discern all who had been infected by SARS-CoV-2, and the use of anti-N as a proxy for breakthrough infections was not valid because of the initial immunization with a whole-virus inactivated vaccine. Third, the sample size and follow-up period were not sufficient to identify less common or late adverse events following booster vaccination, and the immunogenicity data were limited to immune responses through study day 28. Fourth, only immunological data were collected and therefore this investigation lacks information regarding the efficacy of a heterologous mRNA-1273 booster vaccination. Lastly, demographics of the volunteers were not representative of the Indonesian population, and elderly were not represented. In conclusion, our study provides evidence that, after a primary course of CoronaVac inactivated virus vaccine, a heterologous, high-dose mRNA-1273 booster was highly immunogenic and safe, even for those with the lowest pre-boost antibody levels. is the author/funder, who has granted medRxiv a license to display the preprint in (which was not certified by peer review) preprint The copyright holder for this this version posted December 24, 2021. ; https://doi.org/10.1101/2021.12.24.21268360 doi: medRxiv preprint SJD is a scientific advisor to the Scottish Parliament on COVID-19 immunology, for which she receives a fee. Oxford University through EOCRU received funding from SinoVac LifeSciences Ltd, Beijing, China for a vaccine booster trial, unrelated to the current study. All other authors declare that they have no conflict of interest. After publication, the datasets used for this study will be made available to others on reasonable requests to the corresponding author, including a detailed research proposal, study objectives and statistical analysis plan. Deidentified participant data will be provided after written approval from the principal investigators. is the author/funder, who has granted medRxiv a license to display the preprint in (which was not certified by peer review) preprint The copyright holder for this this version posted December 24, 2021. is the author/funder, who has granted medRxiv a license to display the preprint in (which was not certified by peer review) preprint The copyright holder for this this version posted December 24, 2021. is the author/funder, who has granted medRxiv a license to display the preprint in (which was not certified by peer review) preprint The copyright holder for this this version posted December 24, 2021. ; https://doi.org/10.1101/2021.12.24.21268360 doi: medRxiv preprint Waning Immune Humoral Response to BNT162b2 Covid-19 Vaccine over 6 Months Effect of Delta variant on viral burden and vaccine effectiveness against new SARS-CoV-2 infections in the UK Effectiveness of mRNA BNT162b2 COVID-19 vaccine up to 6 months in a large integrated health system in the USA: a retrospective cohort study Waning of BNT162b2 Vaccine Protection against SARS-CoV-2 Infection in Qatar Neutralization of SARS-CoV-2 Omicron variant by sera from BNT162b2 or Coronavac vaccine recipients SARS-CoV-2 variants of concern and variants under investigation in England Technical briefing 31 10 Safety and immunogenicity of heterologous versus homologous prime-boost schedules with an adenoviral vectored and mRNA COVID-19 vaccine (Com-COV): a single-blind, randomised, non-inferiority trial Immune responses against SARS-CoV-2 variants after heterologous and homologous ChAdOx1 nCoV /BNT162b2 vaccination A nationwide cohort study Heterologous SARS-CoV-2 Booster Vaccinations -Preliminary Report Safety and immunogenicity of seven COVID-19 vaccines as a third dose (booster) following two doses of ChAdOx1 nCov-19 or BNT162b2 in the UK (COV-BOOST): a blinded, multicentre, randomised, controlled, phase 2 trial Safety and immunogenicity of the ChAdOx1 nCoV-19 vaccine against SARS-CoV-2: a preliminary report of a phase 1/2, singleblind, randomised controlled trial World Health Organization. WHO recommendation of Sinovac COVID-19 vaccine (Vero Cell Efficacy and safety of an inactivated wholevirion SARS-CoV-2 vaccine (CoronaVac): interim results of a double-blind, randomised, placebo-controlled, phase 3 trial in Turkey Effectiveness of an Inactivated SARS-CoV-2 Vaccine in Chile Effectiveness of CoronaVac among healthcare workers in the setting of high SARS-CoV-2 Gamma variant transmission in Manaus, Brazil: A test-negative case-control study Comparison of the immunogenicity of BNT162b2 and CoronaVac COVID-19 vaccines in Hong Kong seropositivity after rollout of CoronaVac and BNT162b2 COVID-19 vaccines in Chile: a sentinel surveillance study Comparative immunogenicity of mRNA and inactivated vaccines against COVID-19 Immunogenicity and safety of a third dose of CoronaVac, and immune persistence of a two-dose schedule Effectiveness of the CoronaVac vaccine in older adults during a gamma variant associated epidemic of covid-19 in Brazil: test negative case-control study WHO. Meeting of the Strategic Advisory Group of Experts (SAGE) on Immunization 4-7 Indonesia: Coronavirus Pandemic Country Profile Pandemic inequity in a megacity: a multilevel analysis of individual, community and health care vulnerability risks for COVID-19 mortality in Jakarta 27 WHO. EXPERT COMMITTEE ON BIOLOGICAL STANDARDIZATION. Establishment of the WHO International Standard and Reference Panel for anti-SARS-CoV-2 antibody Moderna announces preliminary booster data and updates strategy to address Omikron variant. News release on DSecember 12th Booster-Data-and-Updates-Strategy-to-Address-Omicron-Variant-2021 Safety and immunogenicity of SARS-CoV-2 variant mRNA vaccine boosters in healthy adults: an interim analysis Association of SARS-CoV-2 Seropositive Antibody Test With Risk of Future Infection Correlates of protection against symptomatic and asymptomatic SARS-CoV-2 infection COVID-19 vaccine BNT162b1 elicits human antibody and TH1 T cell responses The authors thank the study participants, the staff at the collaborating clinical sites and the Prodia laboratory.