Cited by 1,055SARS-CoV-2 and COVID-19 ResearchVirus-based gene therapy researchCOVID-19 Clinical Research Studies

Safety and immunogenicity of an rAd26 and rAd5 vector-based heterologous prime-boost COVID-19 vaccine in two formulations: two open, non-randomised phase 1/2 studies from Russia

Open access
Logunov, Denis Y, Dolzhikova, Inna V, Zubkova, Olga V, Tukhvatulin, Amir I, Shcheblyakov, Dmitry V, Dzharullaeva, Alina S, Grousova, Daria M, Erokhova, Alina S +24 more·2020·The Lancet

Abstract

Background We developed a heterologous COVID-19 vaccine consisting of two components, a recombinant adenovirus type 26 (rAd26) vector and a recombinant adenovirus type 5 (rAd5) vector, both carrying the gene for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike glycoprotein (rAd26-S and rAd5-S). We aimed to assess the safety and immunogenicity of two formulations (frozen and lyophilised) of this vaccine. Methods We did two open, non-randomised phase 1/2 studies at two hospitals in Russia. We enrolled healthy adult volunteers (men and women) aged 18-60 years to both studies. In phase 1 of each study, we administered intramuscularly on day 0 either one dose of rAd26-S or one dose of rAd5-S and assessed the safety of the two components for 28 days. In phase 2 of the study, which began no earlier than 5 days after phase 1 vaccination, we administered intramuscularly a prime-boost vaccination, with rAd26-S given on day 0 and rAd5-S on day 21. Primary outcome measures were antigen-specific humoral immunity (SARS-CoV-2-specific antibodies measured by ELISA on days 0, 14, 21, 28, and 42) and safety (number of participants with adverse events monitored throughout the study). Secondary outcome measures were antigen-specific cellular immunity (T-cell responses and interferon-γ concentration) and change in neutralising antibodies (detected with a SARS-CoV-2 neutralisation assay). These trials are registered with ClinicalTrials.gov, NCT04436471 and NCT04437875. Findings Between June 18 and Aug 3, 2020, we enrolled 76 participants to the two studies (38 in each study). In each study, nine volunteers received rAd26-S in phase 1, nine received rAd5-S in phase 1, and 20 received rAd26-S and rAd5-S in phase 2. Both vaccine formulations were safe and well tolerated. The most common adverse events were pain at injection site (44 [58%]), hyperthermia (38 [50%]), headache (32 [42%]), asthenia (21 [28%]), and muscle and joint pain (18 [24%]). Most adverse events were mild and no serious adverse events were detected. All participants produced antibodies to SARS-CoV-2 glycoprotein. At day 42, receptor binding domain-specific IgG titres were 14 703 with the frozen formulation and 11 143 with the lyophilised formulation, and neutralising antibodies were 49·25 with the frozen formulation and 45·95 with the lyophilised formulation, with a seroconversion rate of 100%. Cell-mediated responses were detected in all participants at day 28, with median cell proliferation of 2·5% CD4+ and 1·3% CD8+ with the frozen formulation, and a median cell proliferation of 1·3% CD4+ and 1·1% CD8+ with the lyophilised formulation. Interpretation The heterologous rAd26 and rAd5 vector-based COVID-19 vaccine has a good safety profile and induced strong humoral and cellular immune responses in participants. Further investigation is needed of the effectiveness of this vaccine for prevention of COVID-19. Funding Ministry of Health of the Russian Federation.

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Authors
Logunov, D. Y., Dolzhikova, I. V., Zubkova, O. V., Tukhvatulin, A. I., Shcheblyakov, D. V., Dzharullaeva, A. S., Grousova, D. M., Erokhova, A. S., Kovyrshina, A. V., Botikov, A. G., Izhaeva, F. M., Popova, O., Ozharovskaya, T. A., Esmagambetov, I. B., Favorskaya, I. A., Zrelkin, D. I., Voronina, D. V., Shcherbinin, D. N., Semikhin, A. S., Simakova, Y. V., Tokarskaya, E. A., Lubenets, N. L., Egorova, D. A., Shmarov, M. M., Nikitenko, N. A., Morozova, L. F., Smolyarchuk, E. A., Kryukov, E. V., Babira, V. F., Borisevich, S. V., Naroditsky, B. S., & Gintsburg, A. L.
Affiliations
  • Gamalei Institute of Epidemiology and Microbiology (RU)
  • Ministry of Health of the Russian Federation (RU)
  • Ministry of Defence of the Russian Federation (RU)
Corresponding author
Logunov, Denis Y
Venue
The Lancet
Publisher
Elsevier BV
Published
2020-09
Volume
396
Issue
10255
Pages
887-897
ISSN
  • 0099-5355 (ISSN-L)
  • 0140-6736
OpenAlex
W3083750089
Cited by
1,055
References
27
Citations by year
2026: 13 · 2025: 37 · 2024: 71 · 2023: 97 · 2022: 229 · 2021: 499 · 2020: 107
FWCI
30.61
Type
journal article
Language
en
Update notices
erratum (2021-01-09)
Open access
Locations
  • The Lancet (publishedVersion)
  • PubMed Central (publishedVersion)
  • PubMed (publishedVersion)
Funders
Ministry of Education and Science of the Russian Federation (056-00034-20-02)
Topics
  • Health Sciences › Medicine › Infectious Diseases › SARS-CoV-2 and COVID-19 Research
  • Life Sciences › Biochemistry, Genetics and Molecular Biology › Genetics › Virus-based gene therapy research
  • Health Sciences › Medicine › Infectious Diseases › COVID-19 Clinical Research Studies
Keywords
COVID-19 vaccines, SARS-CoV-2 spike protein, heterologous prime-boost, recombinant adenovirus vector, vaccine safety, immunogenicity, humoral immunity, cell-mediated immunity, T cell response, interferon-gamma, neutralizing antibodies
MeSH terms
Betacoronavirus, COVID-19, SARS-CoV-2, COVID-19 Vaccines, Adenoviridae, Adult, Antibodies, Viral, Female, Humans, Immunoglobulin G, Immunity, Cellular, Immunization, Secondary, Injections, Intramuscular, Male, Pneumonia, Viral, Russia, Viral Vaccines, Coronavirus Infections, Young Adult, Immunity, Humoral, Antibodies, Neutralizing, Pandemics

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