
Among participants who received an incorrect injection, three participants in the mRNA-1273 group received at least one dose of placebo and no dose of mRNA-1273 and were included in the placebo safety population, and three received one dose of placebo and one dose of mRNA-1273 and were included in the mRNA-1273 safety population in the placebo group all seven received mRNA-1273 and were included in the mRNA-1273 safety population. The safety population included all participants who received at least one injection.
#KARLSON MCKENZIE AND HEATHER FULL#
The full analysis population consisted of participants who underwent randomization and received at least one dose of mRNA-1273 or placebo the modified intention-to-treat population comprised participants in the full analysis population who had no immunologic or virologic evidence of Covid-19 on day 1, before the first dose and the per-protocol analysis population included participants in the modified intention-to-treat population who received two doses, with no major protocol deviations. The data cutoff for the primary analysis occurred on November 25, 2020. No other potential conflict of interest relevant to this article was reported. Zaks, being employed by and owning stock options in Moderna. Miller, being employed by and owning stock and stock options in Moderna and Dr. Ivarsson, being employed by and owning share options in Moderna Dr. Han, being employed by and owning stock and stock options in Moderna Dr. Leav, Deng, and Zhou being employees of Moderna Dr. Knightly, being employed by and owning stock and stock options in Moderna Drs. Pajon, being employed by and owning stock in Moderna Dr. Bennett, being employed by and owning stock and stock options in Moderna Dr. Graham, holding pending patent WO/2018/081318 on prefusion coronavirus spike proteins and their use and pending patent 62/972,886 on 2019-nCoV vaccine Dr. Neuzil, receiving grant support from Pfizer Dr. Creech, receiving grant support from Merck, consulting fees from Horizon Pharma and GSK, and fees for serving on a data and safety monitoring board from Astellas Dr. Rouphael, receiving grant support from Pfizer, Merck, Sanofi–Pasteur, Eli Lilly, and Quidel Dr. Baden reports being funded by the NIH to conduct clinical trials in collaboration with Crucell/Janssen and Moderna Dr. (Funded by the Biomedical Advanced Research and Development Authority and the National Institute of Allergy and Infectious Diseases COVE number, NCT04470427.).Ĭopyright © 2020 Massachusetts Medical Society.ĭr.

Aside from transient local and systemic reactions, no safety concerns were identified. The mRNA-1273 vaccine showed 94.1% efficacy at preventing Covid-19 illness, including severe disease. Serious adverse events were rare, and the incidence was similar in the two groups. Moderate, transient reactogenicity after vaccination occurred more frequently in the mRNA-1273 group. Severe Covid-19 occurred in 30 participants, with one fatality all 30 were in the placebo group. 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.

person-years 95% confidence interval, 48.7 to 65.3) and in 11 participants in the mRNA-1273 group (3. Symptomatic Covid-19 illness was confirmed in 185 participants in the placebo group (56. More than 96% of participants received both injections, and 2.2% had evidence (serologic, virologic, or both) of SARS-CoV-2 infection at baseline.
#KARLSON MCKENZIE AND HEATHER TRIAL#
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). 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. 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. This phase 3 randomized, observer-blinded, placebo-controlled trial was conducted at 99 centers across the United States. 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. Vaccines are needed to prevent coronavirus disease 2019 (Covid-19) and to protect persons who are at high risk for complications.
