• Durability of Protection Against Symptomatic COVID-19 Among Participants of the mRNA-1273 SARS-CoV-2 Vaccine Trial.

      Lin, Dan-Yu; Baden, Lindsey R; El Sahly, Hana M; Essink, Brandon; Neuzil, Kathleen M; Corey, Lawrence; Miller, Jacqueline (American Medical Association, 2022-06-01)
    • Efficacy and Safety of the mRNA-1273 SARS-CoV-2 Vaccine

      Baden, Lindsey R; El Sahly, Hana M; Essink, Brandon; Kotloff, Karen; Frey, Sharon; Novak, Rick; Diemert, David; Spector, Stephen A; Rouphael, Nadine; Creech, C Buddy; et al. (Massachusetts Medical Society, 2020-12-30)
      BACKGROUND Vaccines are needed to prevent coronavirus disease 2019 (Covid-19) and to protect persons who are at high risk for complications. The mRNA-1273 vaccine is a lipid nanoparticle-encapsulated mRNA-based vaccine that encodes the prefusion stabilized full-length spike protein of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the virus that causes Covid-19. METHODS This phase 3 randomized, observer-blinded, placebo-controlled trial was conducted at 99 centers across the United States. Persons at high risk for SARS-CoV-2 infection or its complications were randomly assigned in a 1:1 ratio to receive two intramuscular injections of mRNA-1273 (100 μg) or placebo 28 days apart. The primary end point was prevention of Covid-19 illness with onset at least 14 days after the second injection in participants who had not previously been infected with SARS-CoV-2. RESULTS The trial enrolled 30,420 volunteers who were randomly assigned in a 1:1 ratio to receive either vaccine or placebo (15,210 participants in each group). More than 96% of participants received both injections, and 2.2% had evidence (serologic, virologic, or both) of SARS-CoV-2 infection at baseline. Symptomatic Covid-19 illness was confirmed in 185 participants in the placebo group (56.5 per 1000 person-years; 95% confidence interval [CI], 48.7 to 65.3) and in 11 participants in the mRNA-1273 group (3.3 per 1000 person-years; 95% CI, 1.7 to 6.0); vaccine efficacy was 94.1% (95% CI, 89.3 to 96.8%; P<0.001). Efficacy was similar across key secondary analyses, including assessment 14 days after the first dose, analyses that included participants who had evidence of SARS-CoV-2 infection at baseline, and analyses in participants 65 years of age or older. Severe Covid-19 occurred in 30 participants, with one fatality; all 30 were in the placebo group. Moderate, transient reactogenicity after vaccination occurred more frequently in the mRNA-1273 group. Serious adverse events were rare, and the incidence was similar in the two groups. CONCLUSIONS The mRNA-1273 vaccine showed 94.1% efficacy at preventing Covid-19 illness, including severe disease. Aside from transient local and systemic reactions, no safety concerns were identified.
    • Immune correlates analysis of the mRNA-1273 COVID-19 vaccine efficacy clinical trial.

      Gilbert, Peter B; Montefiori, David C; McDermott, Adrian B; Fong, Youyi; Benkeser, David; Deng, Weiping; Zhou, Honghong; Houchens, Christopher R; Martins, Karen; Jayashankar, Lakshmi; et al. (American Association for the Advancement of Science, 2021-11-23)
    • Phase 3 Trial of mRNA-1273 during the Delta-Variant Surge

      Baden, Lindsey R; El Sahly, Hana M; Essink, Brandon; Follmann, Dean; Neuzil, Kathleen M; August, Allison; Clouting, Heather; Fortier, Gabrielle; Deng, Weiping; Han, Shu; et al. (Massachusetts Medical Society, 2021-11-03)