tetano
Editor, Senior Moderator
N Engl J Med
. 2021 Sep 29.
doi: 10.1056/NEJMoa2105290. Online ahead of print.
Phase 3 Safety and Efficacy of AZD1222 (ChAdOx1 nCoV-19) Covid-19 Vaccine
Ann R Falsey[SUP] 1 [/SUP], Magdalena E Sobieszczyk[SUP] 1 [/SUP], Ian Hirsch[SUP] 1 [/SUP], Stephanie Sproule[SUP] 1 [/SUP], Merlin L Robb[SUP] 1 [/SUP], Lawrence Corey[SUP] 1 [/SUP], Kathleen M Neuzil[SUP] 1 [/SUP], William Hahn[SUP] 1 [/SUP], Julie Hunt[SUP] 1 [/SUP], Mark J Mulligan[SUP] 1 [/SUP], Charlene McEvoy[SUP] 1 [/SUP], Edwin DeJesus[SUP] 1 [/SUP], Michael Hassman[SUP] 1 [/SUP], Susan J Little[SUP] 1 [/SUP], Barbara A Pahud[SUP] 1 [/SUP], Anna Durbin[SUP] 1 [/SUP], Paul Pickrell[SUP] 1 [/SUP], Eric S Daar[SUP] 1 [/SUP], Larry Bush[SUP] 1 [/SUP], Joel Solis[SUP] 1 [/SUP], Quito Osuna Carr[SUP] 1 [/SUP], Temitope Oyedele[SUP] 1 [/SUP], Susan Buchbinder[SUP] 1 [/SUP], Jessica Cowden[SUP] 1 [/SUP], Sergio L Vargas[SUP] 1 [/SUP], Alfredo Guerreros Benavides[SUP] 1 [/SUP], Robert Call[SUP] 1 [/SUP], Michael C Keefer[SUP] 1 [/SUP], Beth D Kirkpatrick[SUP] 1 [/SUP], John Pullman[SUP] 1 [/SUP], Tina Tong[SUP] 1 [/SUP], Margaret Brewinski Isaacs[SUP] 1 [/SUP], David Benkeser[SUP] 1 [/SUP], Holly E Janes[SUP] 1 [/SUP], Martha C Nason[SUP] 1 [/SUP], Justin A Green[SUP] 1 [/SUP], Elizabeth J Kelly[SUP] 1 [/SUP], Jill Maaske[SUP] 1 [/SUP], Nancy Mueller[SUP] 1 [/SUP], Kathryn Shoemaker[SUP] 1 [/SUP], Therese Takas[SUP] 1 [/SUP], Richard P Marshall[SUP] 1 [/SUP], Menelas N Pangalos[SUP] 1 [/SUP], Tonya Villafana[SUP] 1 [/SUP], Antonio Gonzalez-Lopez[SUP] 1 [/SUP], AstraZeneca AZD1222 Clinical Study Group
Affiliations
Abstract
Background: The safety and efficacy of the AZD1222 (ChAdOx1 nCoV-19) vaccine in a large, diverse population at increased risk for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in the United States, Chile, and Peru has not been known.
Methods: In this ongoing, double-blind, randomized, placebo-controlled, phase 3 clinical trial, we investigated the safety, vaccine efficacy, and immunogenicity of two doses of AZD1222 as compared with placebo in preventing the onset of symptomatic and severe coronavirus disease 2019 (Covid-19) 15 days or more after the second dose in adults, including older adults, in the United States, Chile, and Peru.
Results: A total of 32,451 participants underwent randomization, in a 2:1 ratio, to receive AZD1222 (21,635 participants) or placebo (10,816 participants). AZD1222 was safe, with low incidences of serious and medically attended adverse events and adverse events of special interest; the incidences were similar to those observed in the placebo group. Solicited local and systemic reactions were generally mild or moderate in both groups. Overall estimated vaccine efficacy was 74.0% (95% confidence interval [CI], 65.3 to 80.5; P<0.001) and estimated vaccine efficacy was 83.5% (95% CI, 54.2 to 94.1) in participants 65 years of age or older. High vaccine efficacy was consistent across a range of demographic subgroups. In the fully vaccinated analysis subgroup, no severe or critical symptomatic Covid-19 cases were observed among the 17,662 participants in the AZD1222 group; 8 cases were noted among the 8550 participants in the placebo group (<0.1%). The estimated vaccine efficacy for preventing SARS-CoV-2 infection (nucleocapsid antibody seroconversion) was 64.3% (95% CI, 56.1 to 71.0; P<0.001). SARS-CoV-2 spike protein binding and neutralizing antibodies increased after the first dose and increased further when measured 28 days after the second dose.
Conclusions: AZD1222 was safe and efficacious in preventing symptomatic and severe Covid-19 across diverse populations that included older adults. (Funded by AstraZeneca and others; ClinicalTrials.gov number, NCT04516746.).
. 2021 Sep 29.
doi: 10.1056/NEJMoa2105290. Online ahead of print.
Phase 3 Safety and Efficacy of AZD1222 (ChAdOx1 nCoV-19) Covid-19 Vaccine
Ann R Falsey[SUP] 1 [/SUP], Magdalena E Sobieszczyk[SUP] 1 [/SUP], Ian Hirsch[SUP] 1 [/SUP], Stephanie Sproule[SUP] 1 [/SUP], Merlin L Robb[SUP] 1 [/SUP], Lawrence Corey[SUP] 1 [/SUP], Kathleen M Neuzil[SUP] 1 [/SUP], William Hahn[SUP] 1 [/SUP], Julie Hunt[SUP] 1 [/SUP], Mark J Mulligan[SUP] 1 [/SUP], Charlene McEvoy[SUP] 1 [/SUP], Edwin DeJesus[SUP] 1 [/SUP], Michael Hassman[SUP] 1 [/SUP], Susan J Little[SUP] 1 [/SUP], Barbara A Pahud[SUP] 1 [/SUP], Anna Durbin[SUP] 1 [/SUP], Paul Pickrell[SUP] 1 [/SUP], Eric S Daar[SUP] 1 [/SUP], Larry Bush[SUP] 1 [/SUP], Joel Solis[SUP] 1 [/SUP], Quito Osuna Carr[SUP] 1 [/SUP], Temitope Oyedele[SUP] 1 [/SUP], Susan Buchbinder[SUP] 1 [/SUP], Jessica Cowden[SUP] 1 [/SUP], Sergio L Vargas[SUP] 1 [/SUP], Alfredo Guerreros Benavides[SUP] 1 [/SUP], Robert Call[SUP] 1 [/SUP], Michael C Keefer[SUP] 1 [/SUP], Beth D Kirkpatrick[SUP] 1 [/SUP], John Pullman[SUP] 1 [/SUP], Tina Tong[SUP] 1 [/SUP], Margaret Brewinski Isaacs[SUP] 1 [/SUP], David Benkeser[SUP] 1 [/SUP], Holly E Janes[SUP] 1 [/SUP], Martha C Nason[SUP] 1 [/SUP], Justin A Green[SUP] 1 [/SUP], Elizabeth J Kelly[SUP] 1 [/SUP], Jill Maaske[SUP] 1 [/SUP], Nancy Mueller[SUP] 1 [/SUP], Kathryn Shoemaker[SUP] 1 [/SUP], Therese Takas[SUP] 1 [/SUP], Richard P Marshall[SUP] 1 [/SUP], Menelas N Pangalos[SUP] 1 [/SUP], Tonya Villafana[SUP] 1 [/SUP], Antonio Gonzalez-Lopez[SUP] 1 [/SUP], AstraZeneca AZD1222 Clinical Study Group
Affiliations
- PMID: 34587382
- DOI: 10.1056/NEJMoa2105290
Abstract
Background: The safety and efficacy of the AZD1222 (ChAdOx1 nCoV-19) vaccine in a large, diverse population at increased risk for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in the United States, Chile, and Peru has not been known.
Methods: In this ongoing, double-blind, randomized, placebo-controlled, phase 3 clinical trial, we investigated the safety, vaccine efficacy, and immunogenicity of two doses of AZD1222 as compared with placebo in preventing the onset of symptomatic and severe coronavirus disease 2019 (Covid-19) 15 days or more after the second dose in adults, including older adults, in the United States, Chile, and Peru.
Results: A total of 32,451 participants underwent randomization, in a 2:1 ratio, to receive AZD1222 (21,635 participants) or placebo (10,816 participants). AZD1222 was safe, with low incidences of serious and medically attended adverse events and adverse events of special interest; the incidences were similar to those observed in the placebo group. Solicited local and systemic reactions were generally mild or moderate in both groups. Overall estimated vaccine efficacy was 74.0% (95% confidence interval [CI], 65.3 to 80.5; P<0.001) and estimated vaccine efficacy was 83.5% (95% CI, 54.2 to 94.1) in participants 65 years of age or older. High vaccine efficacy was consistent across a range of demographic subgroups. In the fully vaccinated analysis subgroup, no severe or critical symptomatic Covid-19 cases were observed among the 17,662 participants in the AZD1222 group; 8 cases were noted among the 8550 participants in the placebo group (<0.1%). The estimated vaccine efficacy for preventing SARS-CoV-2 infection (nucleocapsid antibody seroconversion) was 64.3% (95% CI, 56.1 to 71.0; P<0.001). SARS-CoV-2 spike protein binding and neutralizing antibodies increased after the first dose and increased further when measured 28 days after the second dose.
Conclusions: AZD1222 was safe and efficacious in preventing symptomatic and severe Covid-19 across diverse populations that included older adults. (Funded by AstraZeneca and others; ClinicalTrials.gov number, NCT04516746.).