South African Medical Research Council Vaccines and Infectious Diseases Analytics Research Unit (Wits-VIDA), Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa.
South African Medical Research Council Vaccines and Infectious Diseases Analytics Research Unit (Wits-VIDA), Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa; Department of Clinical Microbiology, Christian Medical College, Vellore, India.
Vaccine. 2023 May 26;41(23):3486-3492. doi: 10.1016/j.vaccine.2023.04.058. Epub 2023 Apr 27.
COVID-19 vaccine efficacy (VE) has been observed to vary against antigenically distinct SARS-CoV-2 variants of concern (VoC). Here we report the final analysis of VE and safety from COV005: a phase 1b/2, multicenter, double-blind, randomized, placebo-controlled study of primary series AZD1222 (ChAdOx1 nCoV-19) vaccination in South African adults aged 18-65 years. South Africa's first, second, and third waves of SARS-CoV-2 infections were respectively driven by the ancestral SARS-CoV-2 virus (wild type, WT), and SARS-CoV-2 Beta and Delta VoCs. VE against asymptomatic and symptomatic infection was 90.6% for WT, 6.7% for Beta and 77.1% for Delta. No cases of severe COVID-19 were documented ahead of unblinding. Safety was consistent with the interim analysis, with no new safety concerns identified. Notably, South Africa's Delta wave occurred ≥ 9 months after primary series vaccination, suggesting that primary series AZD1222 vaccination offers a good durability of protection, potentially due to an anamnestic response. Clinical trial identifier: CT.gov NCT04444674.
COVID-19 疫苗的效力（VE）已被观察到针对具有不同抗原性的 SARS-CoV-2 变体而有所不同。在这里，我们报告了 COV005 的最终 VE 和安全性分析结果：这是一项在南非 18-65 岁成年人中进行的 1b/2 期、多中心、双盲、随机、安慰剂对照的 AZD1222（ChAdOx1 nCoV-19）疫苗初级系列研究。南非的第一波、第二波和第三波 SARS-CoV-2 感染分别由原始 SARS-CoV-2 病毒（野生型，WT）以及 SARS-CoV-2 Beta 和 Delta 变体驱动。WT 对无症状和有症状感染的 VE 为 90.6%，Beta 为 6.7%，Delta 为 77.1%。在揭盲之前，没有记录到严重 COVID-19 病例。安全性与中期分析一致，没有发现新的安全性问题。值得注意的是，南非的 Delta 波发生在初级系列接种疫苗后≥9 个月，这表明初级系列 AZD1222 接种提供了良好的保护持久性，这可能是由于记忆反应。临床试验标识符：CT.gov NCT04444674。
