| Zdroj: |
Heath, P T, Galiza, E P, Baxter, D N, Boffito, M, Browne, D, Burns, F, Chadwick, D R, Clark, R, Cosgrove, C A, Galloway, J, Goodman, A L, Heer, A, Higham, A, Iyengar, S, Jeanes, C, Kalra, P A, Kyriakidou, C, Bradley, J M, Munthali, C, Minassian, A M, McGill, F, Moore, P, Munsoor, I, Nicholls, H, Osanlou, O, Packham, J, Pretswell, C H, Francisco Ramos, A S, Saralaya, D, Sheridan, R P, Smith, R, Soiza, R L, Swift, P A, Thomson, E C, Turner, J, Viljoen, M E, Fries, L, Cho, I, McKnight, I, Glenn, G, Rivers, E J, Robertson, A, Alves, K, Smith, K & Toback, S 2023, ' Safety and efficacy of the NVX-CoV2373 COVID-19 vaccine at completion of the placebo-controlled phase of a randomized controlled trial ', Clinical Infectious Diseases, vol. 76, no. 3, pp. 398–407 . https://doi.org/10.1093/cid/ciac803 |
| Popis: |
BackgroundThe recombinant protein-based vaccine, NVX-CoV2373, demonstrated 89.7% efficacy against coronavirus disease 2019 (COVID-19) in a phase 3, randomized, observer-blinded, placebo-controlled trial in the United Kingdom. The protocol was amended to include a blinded crossover. Data to the end of the placebo-controlled phase are reported.MethodsAdults aged 18–84 years received 2 doses of NVX-CoV2373 or placebo (1:1) and were monitored for virologically confirmed mild, moderate, or severe COVID-19 (onset from 7 days after second vaccination). Participants who developed immunoglobulin G (IgG) against nucleocapsid protein but did not show symptomatic COVID-19 were considered asymptomatic. Secondary outcomes included anti-spike (S) IgG responses, wild-type virus neutralization, and T-cell responses.ResultsOf 15 185 participants, 13 989 remained in the per-protocol efficacy population (6989 NVX-CoV2373, 7000 placebo). At a maximum of 7.5 months (median, 4.5) postvaccination, there were 24 cases of COVID-19 among NVX-CoV2373 recipients and 134 cases among placebo recipients, a vaccine efficacy of 82.7% (95% confidence interval [CI], 73.3%–88.8%). Vaccine efficacy was 100% (95% CI, 17.9%–100.0%) against severe disease and 76.3% (95% CI, 57.4%–86.8%) against asymptomatic disease. High anti-S and neutralization responses to vaccination were evident, together with S-protein–specific induction of interferon-γ secretion in peripheral blood T cells. Incidence of serious adverse events and adverse events of special interest were similar between groups.ConclusionsA 2-dose regimen of NVX-CoV2373 conferred a high level of ongoing protection against asymptomatic, symptomatic, and severe COVID-19 through >6 months postvaccination. A gradual decrease of protection suggests that a booster may be indicated. |
