Efficacy of the ChAdOx1 nCoV-19 Covid-19 Vaccine against the B.1.351 Variant

作者：Shabir A. Madhi, Vicky L. Baillie, Clare Cutland, Merryn Voysey, Anthonet Koen, Lee Fairlie, Sherman D. Padayachee, Keertan Dheda, Shaun Barnabas, Qasim Bhorat, Carmen Briner, Gaurav Kwatra, Khatija Ahmed, Parvinder K. Aley, Sutika Bhikha, Jinal N. Bhiman, As’ad E. Bhorat, Jeanine du Plessis, Aliasgar Esmail, Marisa Groenewald, Elizea Horne, Shi-Hsia Hwa, Aylin Jose, Teresa Lambe, Matt Laubscher, Mookho Malahleha, Masebole Masenya, Mduduzi Masilela, Shakeel McKenzie, Kgaogelo Molapo, Andrew Moultrie, Suzette Oelofse, Faeezah Patel, Sureshnee Pillay, Sarah Rhead, Hylton Rodel, Lindie Rossouw, Carol Taoushanis, Houriiyah Tegally, Asha Thombrayil, Samuel van Eck, Constantinos Kurt Wibmer, Nicholas M. Durham, Elizabeth J. Kelly, Tonya Villafana, Sarah C. Gilbert, Andrew J. Pollard, Túlio de Oliveira, Penny L. Moore, Alex Sigal, Alane Izu · 发表于：New England Journal of Medicine · 年份：2021 · DOI：10.1056/nejmoa2102214 · 被引用次数：1322 · 研究领域：SARS-CoV-2 and COVID-19 Research、COVID-19 Clinical Research Studies、vaccines and immunoinformatics approaches

BACKGROUND: Assessment of the safety and efficacy of vaccines against the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in different populations is essential, as is investigation of the efficacy of the vaccines against emerging SARS-CoV-2 variants of concern, including the B.1.351 (501Y.V2) variant first identified in South Africa. METHODS: viral particles or placebo (0.9% sodium chloride solution) 21 to 35 days apart. Serum samples obtained from 25 participants after the second dose were tested by pseudovirus and live-virus neutralization assays against the original D614G virus and the B.1.351 variant. The primary end points were safety and efficacy of the vaccine against laboratory-confirmed symptomatic coronavirus 2019 illness (Covid-19) more than 14 days after the second dose. RESULTS: Between June 24 and November 9, 2020, we enrolled 2026 HIV-negative adults (median age, 30 years); 1010 and 1011 participants received at least one dose of placebo or vaccine, respectively. Both the pseudovirus and the live-virus neutralization assays showed greater resistance to the B.1.351 variant in serum samples obtained from vaccine recipients than in samples from placebo recipients. In the primary end-point analysis, mild-to-moderate Covid-19 developed in 23 of 717 placebo recipients (3.2%) and in 19 of 750 vaccine recipients (2.5%), for an efficacy of 21.9% (95% confidence interval [CI], -49.9 to 59.8). Among the 42 participants with Covid-19, 39 cases (95.1% of 41 wit...