Journal Article

Safety and Efficacy of NVX-CoV2373 Covid-19 Vaccine


BACKGROUND Early clinical data from studies of the NVX-CoV2373 vaccine (Novavax), a recombinant nanoparticle vaccine against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) that contains the full-length spike glycoprotein of the prototype strain plus Matrix-M adjuvant, showed that the vaccine was safe and associated with a robust immune response in healthy adult participants. Additional data were needed regarding the efficacy, immunogenicity, and safety of this vaccine in a larger population. METHODS In this phase 3, randomized, observer-blinded, placebo-controlled trial conducted at 33 sites in the United Kingdom, we assigned adults between the ages of 18 and 84 years in a 1:1 ratio to receive two intramuscular 5-μg doses of NVX-CoV2373 or placebo administered 21 days apart. The primary efficacy end point was virologically confirmed mild, moderate, or severe SARS-CoV-2 infection with an onset at least 7 days after the second injection in participants who were serologically negative at baseline. RESULTS A total of 15,187 participants underwent randomization, and 14,039 were included in the per-protocol efficacy population. Of the participants, 27.9% were 65 years of age or older, and 44.6% had coexisting illnesses. Infections were reported in 10 participants in the vaccine group and in 96 in the placebo group, with a symptom onset of at least 7 days after the second injection, for a vaccine efficacy of 89.7% (95% confidence interval [CI], 80.2 to 94.6). No hospitalizations or deaths were reported among the 10 cases in the vaccine group. Five cases of severe infection were reported, all of which were in the placebo group. A post hoc analysis showed an efficacy of 86.3% (95% CI, 71.3 to 93.5) against the B.1.1.7 (or alpha) variant and 96.4% (95% CI, 73.8 to 99.5) against non-B.1.1.7 variants. Reactogenicity was generally mild and transient. The incidence of serious adverse events was low and similar in the two groups. CONCLUSIONS A two-dose regimen of the NVX-CoV2373 vaccine administered to adult participants conferred 89.7% protection against SARS-CoV-2 infection and showed high efficacy against the B.1.1.7 variant. (Funded by Novavax; EudraCT number, 2020-004123-16. opens in new tab.)

Attached files


Heath, Paul T.
Galiza, Eva P.
Baxter, David N.
Boffito, Marta
Browne, Duncan
Burns, Fiona
Chadwick, David R.
Clark, Rebecca
Cosgrove, Catherine
Galloway, James
Goodman, Anna L.
Heer, Amardeep
Higham, Andrew
Iyengar, Shalini
Jamal, Arham
Jeanes, Christopher
Kalra, Philip A.
Kyriakidou, Christina
McAuley, Daniel F.
Meyrick, Agnieszka
Minassian, Angela M.
Minton, Jane
Moore, Patrick
Munsoor, Imrozia
Nicholls, Helen
Osanlou, Orod
Packham, Jonathan
Pretswell, Carol H.
Ramos, Alberto San Francisco
Saralaya, Dinesh
Sheridan, Ray P.
Smith, Richard
Soiza, Roy L.
Swift, Pauline A.
Thomson, Emma C.
Turner, Jeremy
Viljoen, Marianne E.
Albert, Gary
Cho, Iksung
Dubovsky, Filip
Glenn, Greg
Rivers, Joy
Robertson, Andreana
Smith, Kathy
Toback, Seth (for the 2019nCoV-302 Study Group)

Oxford Brookes departments

Oxford School of Nursing and Midwifery


Year of publication: 2021
Date of RADAR deposit: 2022-01-12

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