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    Home > Active Ingredient News > Infection > NEJM publishes Phase 3 results of Johnson & Johnson's single-dose new crown vaccine: prevent 2/3 of moderate to severe diseases, effective in South Africa

    NEJM publishes Phase 3 results of Johnson & Johnson's single-dose new crown vaccine: prevent 2/3 of moderate to severe diseases, effective in South Africa

    • Last Update: 2021-05-09
    • Source: Internet
    • Author: User
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    ▎The content team editor of WuXi AppTec today, the New England Journal of Medicine published the results of the Phase 3 trial of the new crown vaccine Ad26.
    S developed by Johnson & Johnson.

    Data shows that the protective effect of Ad26.
    S vaccine against moderate to severe new coronavirus disease (COVID-19) reached 66.
    1% 28 days after vaccination.
    It also showed a better protective effect in South Africa, where mutant strains are prevalent, and at the same time, it is asymptomatic.
    Infection has a certain degree of protection.

    Screenshot source: The New England Journal of Medicine This Ad26.
    S vaccine uses an adenovirus type 26 (Ad26) vector to express the unique "spike" protein of the new coronavirus.

    The modification of Ad26 makes it unable to replicate in the human body and cause disease.

    After people are vaccinated with this vaccine, the body can temporarily produce spike protein.
    This protein does not cause disease, but triggers the immune system's defense response to produce an immune response against the new coronavirus.

    This vaccine is given in a single dose.

    In this international, randomized, double-blind, placebo-controlled phase 3 trial, adult subjects were randomized 1:1 to receive a single dose of Ad26.
    S or placebo.

    The trial was enrolled on September 21, 2020, and the data cut-off date for this analysis is January 22, 2021.

    19,630 COVID-19-negative subjects received the Ad26.
    S vaccine, and 19,691 COVID-19-negative subjects received a placebo.

    The median follow-up time was 58 days, and 55% of subjects were followed up for at least 8 weeks.

    The main endpoint of the vaccine protection effect test is the protection against moderate to severe COVID-19 14 days and 28 days after vaccination.

    Data show that Ad26.
    S vaccine can prevent moderate to severe COVID-19, with a protective effect of 66.
    9% 14 days after vaccination (116 cases in the vaccine group and 348 cases in the placebo group), and a protective effect of 66.
    1% after 28 days of vaccination (66 in the vaccine group) Cases, 193 cases in the placebo group).

    For severe and critical COVID-19 cases, the protective effect is better, with a protective effect of 76.
    7% 14 days after vaccination and 85.
    4% after 29 days of vaccination.

    Although 86 of the 91 cases in South Africa (94.
    5%) carried the 20H/501Y.
    V2 mutant virus, 14 and 28 days after vaccination, the protective efficacy of the vaccine against moderate to severe COVID-19 still reached 52.
    0% and 64%.
    The protection effectiveness of severe and critical COVID-19 reached 73.
    1% and 81.

    ▲The incidence of moderate to severe COVID-19 cases (A), severe and critical COVID-19 cases (B), and severe and critical COVID-19 cases (C) in South Africa after inoculation of Ad26.
    S vaccine (picture source: reference material) [1]) For the analysis of the preventive effect of asymptomatic infection, all 2650 subjects who obtained serum analysis results 71 days after vaccination were included.

    There were 18 asymptomatic infections in the vaccine group and 50 asymptomatic infections in the placebo group.
    The preliminary analysis showed that the vaccine's protective efficacy against asymptomatic infections was 65.

    The safety performance of Ad26.
    S is higher than that of placebo, but it is generally mild to moderate and short-lived.

    In the vaccine group, pain at the injection site was the most common local reaction (48.
    6%); the most common systemic reactions were headache (38.
    9%), fatigue (38.
    2%), myalgia (33.
    2%) and nausea (14.

    The incidence of serious adverse events was similar between the two groups.

    The research team observed more venous thromboembolism events in the vaccine group (11 cases in the vaccine group vs.
    3 cases in the placebo group).

    Most of these subjects have underlying underlying diseases and predisposing factors that may cause these thrombotic events.

    In addition, there were more seizures (4 cases vs.
    1 case) and tinnitus (6 cases vs.
    0 cases) in the vaccine group.
    The research team stated in the paper that it is currently unable to determine the causal relationship between these events and Ad26.
    Continue monitoring after the vaccine is marketed.

    There were 3 deaths in the vaccine group (all not related to COVID-19), and 16 deaths in the placebo group (5 cases related to COVID-19).

    Image source: 123RF Based on these data, the research team believes that a single dose of Ad26.
    S can prevent symptomatic COVID-19 and asymptomatic new crown infections, and can effectively prevent severe illness (including hospitalization and death).

    The safety is similar to other phase 3 trials of the new crown vaccine.

    New crown research related reading "The Lancet", NEJM reported 3 cases in detail! What are the symptoms and causes of thrombosis after COVID-19 vaccination? What is the cause of cerebral thrombosis after vaccination with the new crown vaccine? You must understand these questions for the first time to reveal the potential mechanism of thrombosis after the new crown vaccination! NEJM released two heavy research reference materials[1] Jerald Sadoff,, et al.
    , (2021).
    Safety and Efficacy of Single-Dose Ad26.
    S Vaccine against Covid-19.
    The N Engl J Med, DOI: 10.
    1056/NEJMoa2101544 Note: This article aims to introduce the progress of medical and health research, and is not a treatment plan recommendation.

    If you need guidance on treatment plans, please go to a regular hospital for treatment.

    This article is an English version of an article which is originally in the Chinese language on and is provided for information purposes only. This website makes no representation or warranty of any kind, either expressed or implied, as to the accuracy, completeness ownership or reliability of the article or any translations thereof. If you have any concerns or complaints relating to the article, please send an email, providing a detailed description of the concern or complaint, to A staff member will contact you within 5 working days. Once verified, infringing content will be removed immediately.
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