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Frontiers in Immunology 2021The World Health Organization declared the coronavirus disease 2019 (COVID-19) pandemic on March 11, 2020. Two vaccine types were developed using two different...
INTRODUCTION
The World Health Organization declared the coronavirus disease 2019 (COVID-19) pandemic on March 11, 2020. Two vaccine types were developed using two different technologies: viral vectors and mRNA. Thrombosis is one of the most severe and atypical adverse effects of vaccines. This study aimed to analyze published cases of thrombosis after COVID-19 vaccinations to identify patients' features, potential pathophysiological mechanisms, timing of appearance of the adverse events, and other critical issues.
MATERIALS AND METHODS
We performed a systematic electronic search of scientific articles regarding COVID-19 vaccine-related thrombosis and its complications on the PubMed (MEDLINE) database and through manual searches. We selected 10 out of 50 articles from February 1 to May 5, 2021 and performed a descriptive analysis of the adverse events caused by the mRNA-based Pfizer and Moderna vaccines and the adenovirus-based AstraZeneca vaccine.
RESULTS
In the articles on the Pfizer and Moderna vaccines, the sample consisted of three male patients with age heterogeneity. The time from vaccination to admission was ≤3 days in all cases; all patients presented signs of petechiae/purpura at admission, with a low platelet count. In the studies on the AstraZeneca vaccine, the sample consisted of 58 individuals with a high age heterogeneity and a high female prevalence. Symptoms appeared around the ninth day, and headache was the most common symptom. The platelet count was below the lower limit of the normal range. All patients except one were positive for PF4 antibodies. The cerebral venous sinus was the most affected site. Death was the most prevalent outcome in all studies, except for one study in which most of the patients remained alive.
DISCUSSION
Vaccine-induced thrombotic thrombocytopenia (VITT) is an unknown nosological phenomenon secondary to inoculation with the COVID-19 vaccine. Several hypotheses have been formulated regarding its physiopathological mechanism. Recent studies have assumed a mechanism that is assimilable to heparin-induced thrombocytopenia, with protagonist antibodies against the PF4-polyanion complex. Viral DNA has a negative charge and can bind to PF4, causing VITT. New experimental studies have assumed that thrombosis is related to a soluble adenoviral protein spike variant, originating from splicing events, which cause important endothelial inflammatory events, and binding to endothelial cells expressing ACE2.
CONCLUSION
Further studies are needed to better identify VITT's pathophysiological mechanisms and genetic, demographic, or clinical predisposition of high-risk patients, to investigate the correlation of VITT with the different vaccine types, and to test the significance of the findings.
Topics: 2019-nCoV Vaccine mRNA-1273; Antigen-Antibody Complex; BNT162 Vaccine; COVID-19; Cerebral Veins; ChAdOx1 nCoV-19; Female; Headache; Humans; Mass Vaccination; Platelet Factor 4; SARS-CoV-2; Sex Factors; Survival Analysis; Thrombosis
PubMed: 34912330
DOI: 10.3389/fimmu.2021.729251 -
Frontiers in Immunology 2021There is a significant research gap in meta-analysis on the efficacy and safety of coronavirus disease 2019 (COVID-19) vaccines. This study analyzed the efficacy of... (Meta-Analysis)
Meta-Analysis
There is a significant research gap in meta-analysis on the efficacy and safety of coronavirus disease 2019 (COVID-19) vaccines. This study analyzed the efficacy of COVID-19 vaccines. Published phase I, phase II, and phase III trials analyzing safety and immunogenicity and phase III randomized clinical trials evaluating the efficacy of COVID-19 vaccines were included. We searched MEDLINE, Scopus, and The Lancet for published articles evaluating the relative reduction in COVID-19 risk after vaccination. Selected literatures were published between December 15, 2019 and May 15, 2021 on the safety, efficacy, and immunogenicity of COVID-19 vaccines. This meta-analysis included studies that confirmed cases of COVID-19 using reverse transcriptase polymerase chain reaction. This study detected 8,926 eligible research articles published on COVID-19 vaccines. Of these, 25 studies fulfilled the inclusion criteria. Among the selected articles, 19 randomized clinical trials, 2 non-randomized clinical trials, and 3 observational studies were analyzed. Seven (28%) studies were included in the meta-analysis. The efficacy of the adenovirus vector vaccine was 73% (95% CI = 69-77) and that of the messenger RNA (mRNA) vaccine was 85% (95% CI = 82-88) in participants aged ≥18 years. There are no reports of clinical trials in participants aged under 16 years. The production of neutralizing antibodies against receptor-binding domains (RBDs) of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in >90% of the vaccinated samples was reported within 0-30 days of the first or the second dose of the vaccine. Pain at the injection site was the most common local symptom in people receiving mRNA vaccines (29%-85% of participants). Fever (0.2%-95%) was the most prevalent in people receiving adenovirus vector vaccines, and fatigue (8.4%-55%) was the most common side effect in people receiving the mRNA vaccines. Studies suggest that mRNA vaccines and adenovirus vector vaccines can provide moderate to high protection against COVID-19 infection in people over 18 years. Evidence of the long-term protection of the vaccines in people aged under 16 years against the multiple variants of COVID-19 are limited. This study will provide an integrated evaluation on the efficacy, safety, and immunogenicity of the COVID-19 vaccines.
Topics: Adolescent; Adult; Aged; Antibodies, Neutralizing; COVID-19; COVID-19 Vaccines; Humans; Immunogenicity, Vaccine; Injections, Intramuscular; Middle Aged; Pain; Randomized Controlled Trials as Topic; SARS-CoV-2; Young Adult
PubMed: 34707602
DOI: 10.3389/fimmu.2021.714170 -
Clinical Infectious Diseases : An... Sep 2022Rare cases of thrombosis and thrombocytopenia (thrombosis with thrombocytopenia syndrome [TTS]) have been associated with 2 coronavirus disease 2019 adenovirus vector... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Rare cases of thrombosis and thrombocytopenia (thrombosis with thrombocytopenia syndrome [TTS]) have been associated with 2 coronavirus disease 2019 adenovirus vector vaccines: the ChAdOx1 nCoV-19 Vaxzevria vaccine (Oxford/AstraZeneca) and the JNJ-7836735 Johnson & Johnson vaccine (Janssen). It is unknown if TTS is a class-mediated effect of adenovirus-based vaccines or if it could worsen known hypercoagulable states. Since most cases of TTS happen in women of childbearing age, pregnancy is a crucial risk factor to assess. Understanding these risks is important for advising vaccine recipients and future adenovirus vector vaccine development.
METHODS
To explore the potential associations of adenovirus-based vaccine components with symptoms of TTS in the general clinical trial population and in pregnant women in clinical trials, we conducted a systematic review and meta-analysis of adenovirus-based vector vaccines to document cases of thrombocytopenia, coagulopathy, and or pregnancy from 1 January 1966 to 9 August 2021.
RESULTS
We found 167 articles from 159 studies of adenovirus vector-based vaccines, 123 of which targeted infectious diseases. In the general population, 20 studies reported an event of thrombocytopenia and 20 studies indicated some coagulopathy. Among pregnant women, of the 28 studies that reported a total of 1731 pregnant women, thrombocytopenia or coagulopathy were not reported.
CONCLUSIONS
In this systematic review and meta-analysis, there was no class-wide effect of adenovirus vector vaccines toward thrombocytopenia or coagulopathy events in the general population or in pregnant women.
Topics: Adenoviridae; Adenovirus Vaccines; COVID-19; ChAdOx1 nCoV-19; Female; Humans; Pregnancy; Thrombocytopenia; Thrombosis; Vaccines
PubMed: 35134164
DOI: 10.1093/cid/ciac080 -
Vaccines Mar 2020Optimal vaccine dosing is important to ensure the greatest protection and safety. Analysis of dose-response data, from previous studies, may inform future studies to... (Review)
Review
Immunologic Dose-Response to Adenovirus-Vectored Vaccines in Animals and Humans: A Systematic Review of Dose-Response Studies of Replication Incompetent Adenoviral Vaccine Vectors when Given via an Intramuscular or Subcutaneous Route.
Optimal vaccine dosing is important to ensure the greatest protection and safety. Analysis of dose-response data, from previous studies, may inform future studies to determine the optimal dose. Implementing more quantitative modelling approaches in vaccine dose finding have been recently suggested to accelerate vaccine development. Adenoviral vectored vaccines are in advanced stage of development for a variety of prophylactic and therapeutic indications, however dose-response has not yet been systematically determined. To further inform adenoviral vectored vaccines dose identification, historical dose-response data should be systematically reviewed. A systematic literature review was conducted to collate and describe the available dose-response studies for adenovirus vectored vaccines. Of 2787 papers identified by Medline search strategy, 35 were found to conform to pre-defined criteria. The majority of studies were in mice or humans and studied adenovirus serotype 5. Dose-response data were available for 12 different immunological responses. The majority of papers evaluated three dose levels, only two evaluated more than five dose levels. The most common dosing range was 10-10 viral particles in mouse studies and 10-10 viral particles in human studies. Data were available on adenovirus vaccine dose-response, primarily on adenovirus serotype 5 backbones and in mice and humans. These data could be used for quantitative adenoviral vectored vaccine dose optimisation analysis.
PubMed: 32192058
DOI: 10.3390/vaccines8010131 -
Journal of Advanced Pharmaceutical... 2021Search for an effective and safe vaccine to prevent transmission of current pandemic is an unmet need. This study reviews and compares the available early phase clinical... (Review)
Review
Search for an effective and safe vaccine to prevent transmission of current pandemic is an unmet need. This study reviews and compares the available early phase clinical data of vaccine candidates which have reached phase 3 of clinical development. The latest update of "DRAFT landscape of coronavirus (CoV) disease 2019 candidate vaccines (October 2, 2020)" released by the World Health Organization was accessed to identify the potential vaccine candidates. The full text articles (published and/or preprint) of data of early clinical trials of the selected vaccines were accessed from the links provided in the same document, PubMed and/or medRxiv.com. After extraction and synthesis, the data were critically evaluated for the study efficacy and safety outcomes. Of the total 193 candidate vaccines 10 were found to reach phase 3 of the clinical development. Nine of these were included in the evaluation process. In all of the included studies, immunogenicity and serious adverse events/local or systemic adverse events/laboratory parameters abnormality was considered as efficacy and safety outcomes respectively. Immunogenicity response with most of the vaccines was either higher than or similar to the respective controls except one (recombinant adenovirus type 26 COV2 [Ad26.COV2.S]) for which it was less than that in control. Overall adverse events (related and/or unrelated) were more with vaccines than those with respective control(s) in three studies, in other two, these were similar whereas in one study, the events were less in the vaccine group than in control group and in the rest, data described were descriptive only without any mention for the same for the control. In conclusion all studies showed immunogenic response to target protein of severe acute respiratory syndrome CoV-2 and which was higher than the respective control except for Ad26.CoV2.S. Many of the vaccines caused more adverse events than the controls, however most were mild and transient and/or manageable.
PubMed: 34345597
DOI: 10.4103/japtr.JAPTR_229_20 -
Vaccine Jan 2021Recent deadly outbreaks of Marburg virus underscore the need for an effective vaccine. A summary of the latest research is needed for this WHO priority pathogen. This... (Review)
Review
BACKGROUND
Recent deadly outbreaks of Marburg virus underscore the need for an effective vaccine. A summary of the latest research is needed for this WHO priority pathogen. This systematic review aimed to determine progress towards a vaccine for Marburg virus.
METHODS
Article search criteria were developed to query PubMed for peer-reviewed articles from 1990 through 2019 on Marburg virus vaccine clinical trials in humans and pre-clinical studies in non-human primates (NHP). Abstracts were reviewed by two authors. Relevant articles were reviewed in full. Discrepancies were resolved by a third author. Data abstracted included year, author, title, vaccine construct, number of subjects, efficacy, and demographics. Assessment for risk of bias was performed using the Syrcle tool for animal studies, and the Cochrane Collaboration risk of bias tool for human studies.
RESULTS
101 articles were identified; 27 were related to Marburg vaccines. After full text review, 21 articles were selected. 215 human subjects were in three phase 1 clinical trials, and 203 NHP in 18 studies. Vaccine constructs were DNA plasmids, recombinant vesicular stomatitis virus (VSV) vectors, adenovirus vectors, virus-like particles (VLP), among others. Two human phase 1 studies of DNA vaccines had 4 adverse effects requiring vaccine discontinuation among 128 participants and 31-80% immunogenicity. In NHP challenge studies, 100% survival was seen in 6 VSV vectored vaccines, 2 DNA vaccines, 2 VLP vaccines, and in 1 adenoviral vectored vaccine.
CONCLUSION
In human trials, two Marburg DNA vaccines provided either low immunogenicity or a failure to elicit durable immunity. A variety of NHP candidate Marburg vaccines demonstrated favorable survival and immunogenicity parameters, to include VSV, VLP, and adenoviral vectored vaccines. Elevated binding antibodies appeared to be consistently associated with protection across the NHP challenge studies. Further human trials are needed to advance vaccines to limit the spread of this highly lethal virus.
Topics: Animals; Ebolavirus; Hemorrhagic Fever, Ebola; Humans; Marburgvirus; Primates; Viral Vaccines
PubMed: 33309082
DOI: 10.1016/j.vaccine.2020.11.042 -
BMJ (Clinical Research Ed.) May 2022To evaluate the effectiveness of heterologous and homologous covid-19 vaccine regimens with and without boosting in preventing covid-19 related infection, hospital... (Meta-Analysis)
Meta-Analysis
OBJECTIVE
To evaluate the effectiveness of heterologous and homologous covid-19 vaccine regimens with and without boosting in preventing covid-19 related infection, hospital admission, and death.
DESIGN
Living systematic review and network meta-analysis.
DATA SOURCES
World Health Organization covid-19 databases, including 38 sources of published studies and preprints.
STUDY SELECTION
Randomised controlled trials, cohort studies, and case-control studies.
METHODS
38 WHO covid-19 databases were searched on a weekly basis from 8 March 2022 to 31 July 2022. Studies that assessed the effectiveness of heterologous and homologous covid-19 vaccine regimens with or without a booster were identified. Studies were eligible when they reported the number of documented, symptomatic, severe covid-19 infections, covid-19 related hospital admissions, or covid-19 related deaths among populations that were vaccinated and unvaccinated. The primary measure was vaccine effectiveness calculated as 1−odds ratio. Secondary measures were surface under the cumulative ranking curve (SUCRA) scores and the relative effects for pairwise comparisons. The risk of bias was evaluated by using the risk of bias in non-randomised studies of interventions (ROBINS-I) tool for all cohort and case-control studies. The Cochrane risk of bias tool (version 2; ROB-2) was used to assess randomised controlled trials.
RESULTS
The second iteration of the analysis comprised 63 studies. 25 combinations of covid-19 vaccine regimens were identified, of which three doses of mRNA vaccine were found to be 93% (95% credible interval 70% to 98%) effective against asymptomatic or symptomatic covid-19 infections for non-delta or non-omicron related infections. Heterologous boosting using two dose adenovirus vector vaccines with one dose mRNA vaccine showed a vaccine effectiveness of 94% (72% to 99%) against non-delta or non-omicron related asymptomatic or symptomatic infections. Three doses of mRNA vaccine were found to be the most effective in reducing non-delta or non-omicron related hospital admission (96%, 82% to 99%). The vaccine effectiveness against death in people who received three doses of mRNA vaccine remains uncertain owing to confounders. The estimate for a four dose mRNA vaccine regimen was of low certainty, as only one study on the effectiveness of four doses could be included in this update. More evidence on four dose regimens will be needed to accurately assess the effectiveness of a fourth vaccine dose. For people with delta or omicron related infection, a two dose regimen of an adenovirus vector vaccine with one dose of mRNA booster was 77% (42% to 91%) effective against asymptomatic or symptomatic covid-19 infections, and a three dose regimen of a mRNA vaccine was 93% (76% to 98%) effective against covid-19 related hospital admission.
CONCLUSION
An mRNA booster is recommended to supplement any primary vaccine course. Heterologous and homologous three dose regimens work comparably well in preventing covid-19 infections, even against different variants. The effectiveness of three dose vaccine regimens against covid-19 related death remains uncertain.
SYSTEMATIC REVIEW REGISTRATION
This review was not registered. The protocol is included in the supplementary document.
READERS' NOTE
This article is a living systematic review that will be updated to reflect emerging evidence. Updates may occur for up to two years from the date of original publication. This version is update 1 of the original article published on 31 May 2022 (BMJ 2022;377:e069989), and previous versions can be found as data supplements (https://www.bmj.com/content/377/bmj-2022-069989/related). When citing this paper please consider adding the version number and date of access for clarity.
Topics: Aged; COVID-19; COVID-19 Vaccines; Humans; Network Meta-Analysis; RNA, Messenger; SARS-CoV-2; Vaccines, Synthetic; mRNA Vaccines
PubMed: 35640925
DOI: 10.1136/bmj-2022-069989 -
Journal of Neurology Mar 2024Case-reports/series and cohorts of Guillain-Barré syndrome (GBS) associated with COVID-19 vaccination have been reported. (Meta-Analysis)
Meta-Analysis
BACKGROUND
Case-reports/series and cohorts of Guillain-Barré syndrome (GBS) associated with COVID-19 vaccination have been reported.
METHODS
A systematic review and meta-analysis of cohort studies of GBS after COVID-19 vaccination was carried out. Incidence and incidence rate ratio for a number of vaccine doses and risk of GBS, also considering the specific vaccine technology, were calculated in a random-effects model.
RESULTS
Of 554 citations retrieved, 518 were discarded as irrelevant. We finally included 15 studies. The random effect model yielded, regardless of the vaccine technology, 1.25 (95%CI 0.21; 2.83) GBS cases per million of COVID-19 vaccine doses, 3.93 (2.54; 5.54) cases per million doses for adenovirus-vectored vaccines and 0.69 (0.38; 1.06) cases per million doses for mRNA vaccines. The GBS risk was 2.6 times increased with the first dose. Regardless of the vaccine technology, the GBS risk was not increased but disaggregating the data it was 2.37 (1.67; 3.36) times increased for adenovirus-vectored vaccines and 0.32 (0.23; 0.47) for mRNA vaccines. Mortality for GBS after vaccination was 0.10 per million doses and 4.6 per GBS cases.
CONCLUSIONS
Adenovirus-vectored vaccines showed a 2.4 times increased risk of GBS that was about seven times higher compared with mRNA-based vaccines. The decreased GBS risk associated with mRNA vaccines was possibly due to an elicited reduction of infections, including SARS-CoV-2, associated with GBS during the vaccination period. How adenovirus-vectored COVID-19 vaccines may trigger GBS is unclear and further studies should investigate the relationship between vaccine technologies and GBS risk.
Topics: Humans; COVID-19; COVID-19 Vaccines; Guillain-Barre Syndrome; mRNA Vaccines; Vaccination
PubMed: 38233678
DOI: 10.1007/s00415-024-12186-7 -
The Cochrane Database of Systematic... Dec 2022The common cold is a spontaneously remitting infection of the upper respiratory tract, characterised by a runny nose, nasal congestion, sneezing, cough, malaise, sore... (Review)
Review
BACKGROUND
The common cold is a spontaneously remitting infection of the upper respiratory tract, characterised by a runny nose, nasal congestion, sneezing, cough, malaise, sore throat, and fever (usually < 37.8 ºC). Whilst the common cold is generally not harmful, it is a cause of economic burden due to school and work absenteeism. In the United States, economic loss due to the common cold is estimated at more than USD 40 billion per year, including an estimate of 70 million workdays missed by employees, 189 million school days missed by children, and 126 million workdays missed by parents caring for children with a cold. Additionally, data from Europe show that the total cost per episode may be up to EUR 1102. There is also a large expenditure due to inappropriate antimicrobial prescription. Vaccine development for the common cold has been difficult due to antigenic variability of the common cold viruses; even bacteria can act as infective agents. Uncertainty remains regarding the efficacy and safety of interventions for preventing the common cold in healthy people, thus we performed an update of this Cochrane Review, which was first published in 2011 and updated in 2013 and 2017.
OBJECTIVES
To assess the clinical effectiveness and safety of vaccines for preventing the common cold in healthy people.
SEARCH METHODS
We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (April 2022), MEDLINE (1948 to April 2022), Embase (1974 to April 2022), CINAHL (1981 to April 2022), and LILACS (1982 to April 2022). We also searched three trials registers for ongoing studies, and four websites for additional trials (April 2022). We did not impose any language or date restrictions.
SELECTION CRITERIA
Randomised controlled trials (RCTs) of any virus vaccine compared with placebo to prevent the common cold in healthy people.
DATA COLLECTION AND ANALYSIS
We used Cochrane's Screen4Me workflow to assess the initial search results. Four review authors independently performed title and abstract screening to identify potentially relevant studies. We retrieved the full-text articles for those studies deemed potentially relevant, and the review authors independently screened the full-text reports for inclusion in the review, recording reasons for exclusion of the excluded studies. Any disagreements were resolved by discussion or by consulting a third review author when needed. Two review authors independently collected data on a data extraction form, resolving any disagreements by consensus or by involving a third review author. We double-checked data transferred into Review Manager 5 software. Three review authors independently assessed risk of bias using RoB 1 tool as outlined in the Cochrane Handbook for Systematic Reviews of Interventions. We carried out statistical analysis using Review Manager 5. We did not conduct a meta-analysis, and we did not assess publication bias. We used GRADEpro GDT software to assess the certainty of the evidence and to create a summary of findings table. MAIN RESULTS: We did not identify any new RCTs for inclusion in this update. This review includes one RCT conducted in 1965 with an overall high risk of bias. The RCT included 2307 healthy young men in a military facility, all of whom were included in the analyses, and compared the effect of three adenovirus vaccines (live, inactivated type 4, and inactivated type 4 and 7) against a placebo (injection of physiological saline or gelatin capsule). There were 13 (1.14%) events in 1139 participants in the vaccine group, and 14 (1.19%) events in 1168 participants in the placebo group. Overall, we do not know if there is a difference between the adenovirus vaccine and placebo in reducing the incidence of the common cold (risk ratio 0.95, 95% confidence interval 0.45 to 2.02; very low-certainty evidence). Furthermore, no difference in adverse events when comparing live vaccine preparation with placebo was reported. We downgraded the certainty of the evidence to very low due to unclear risk of bias, indirectness because the population of this study was only young men, and imprecision because confidence intervals were wide and the number of events was low. The included study did not assess vaccine-related or all-cause mortality. AUTHORS' CONCLUSIONS: This Cochrane Review was based on one study with very low-certainty evidence, which showed that there may be no difference between the adenovirus vaccine and placebo in reducing the incidence of the common cold. We identified a need for well-designed, adequately powered RCTs to investigate vaccines for the common cold in healthy people. Future trials on interventions for preventing the common cold should assess a variety of virus vaccines for this condition, and should measure such outcomes as common cold incidence, vaccine safety, and mortality (all-cause and related to the vaccine).
Topics: Child; Humans; Male; Adenovirus Vaccines; Common Cold; Incidence; Systematic Reviews as Topic; Vaccines, Attenuated; Randomized Controlled Trials as Topic
PubMed: 36515550
DOI: 10.1002/14651858.CD002190.pub6 -
Journal of Medical Virology Dec 2021To systematically evaluate the effectiveness and safety of the SARS-CoV-2 vaccines currently undergoing clinical trials. (Review)
Review Meta-Analysis
OBJECTIVE
To systematically evaluate the effectiveness and safety of the SARS-CoV-2 vaccines currently undergoing clinical trials.
METHODS
PubMed, EMBASE, and Cochrane Library databases were searched to collect open human COVID-19 vaccines randomized controlled trials, without limiting the search time and language. The research papers collected in the above-mentioned databases were initially screened according to the title and abstract content and merged, and the repeated ones were removed. After reading the full text of the remaining research, the studies that did not meet the inclusion criteria were excluded, and finally, nine studies were obtained. After extracting the statistical data of adverse events in the study, load them into Review Manager for heterogeneity analysis.
RESULTS
The incidence of adverse reactions of inactivated virus vaccines, RNA vaccines, and adenovirus vector vaccines was higher than that of placebo. Common adverse reactions included pain, swelling, and fever at the injection site.
CONCLUSION
From the perspective of effectiveness, RNA vaccine > adenovirus vector vaccine > inactivated virus vaccine. From the perspective of safety, the incidence of adverse reactions of the three vaccines is higher than that of a placebo, and the incidence of adverse reactions of the adenovirus vector vaccine is higher.
Topics: Adenovirus Vaccines; COVID-19; COVID-19 Vaccines; Humans; SARS-CoV-2; Spike Glycoprotein, Coronavirus; Vaccination; Vaccines, Inactivated; Vaccines, Synthetic
PubMed: 34264528
DOI: 10.1002/jmv.27203