Center for Virology and Vaccine Research, Beth Israel Deaconess Medical Center, Boston, Massachusetts.
Ragon Institute of MGH, MIT and Harvard, Cambridge, Massachusetts.
JAMA. 2021 Apr 20;325(15):1535-1544. doi: 10.1001/jama.2021.3645.
Control of the global COVID-19 pandemic will require the development and deployment of safe and effective vaccines.
To evaluate the immunogenicity of the Ad26.COV2.S vaccine (Janssen/Johnson & Johnson) in humans, including the kinetics, magnitude, and phenotype of SARS-CoV-2 spike-specific humoral and cellular immune responses.
DESIGN, SETTING, AND PARTICIPANTS: Twenty-five participants were enrolled from July 29, 2020, to August 7, 2020, and the follow-up for this day 71 interim analysis was completed on October 3, 2020; follow-up to assess durability will continue for 2 years. This study was conducted at a single clinical site in Boston, Massachusetts, as part of a randomized, double-blind, placebo-controlled phase 1 clinical trial of Ad26.COV2.S.
Participants were randomized to receive 1 or 2 intramuscular injections with 5 × 1010 viral particles or 1 × 1011 viral particles of Ad26.COV2.S vaccine or placebo administered on day 1 and day 57 (5 participants in each group).
Humoral immune responses included binding and neutralizing antibody responses at multiple time points following immunization. Cellular immune responses included immunospot-based and intracellular cytokine staining assays to measure T-cell responses.
Twenty-five participants were randomized (median age, 42; age range, 22-52; 52% women, 44% male, 4% undifferentiated), and all completed the trial through the day 71 interim end point. Binding and neutralizing antibodies emerged rapidly by day 8 after initial immunization in 90% and 25% of vaccine recipients, respectively. By day 57, binding and neutralizing antibodies were detected in 100% of vaccine recipients after a single immunization. On day 71, the geometric mean titers of spike-specific binding antibodies were 2432 to 5729 and the geometric mean titers of neutralizing antibodies were 242 to 449 in the vaccinated groups. A variety of antibody subclasses, Fc receptor binding properties, and antiviral functions were induced. CD4+ and CD8+ T-cell responses were induced.
In this phase 1 study, a single immunization with Ad26.COV2.S induced rapid binding and neutralization antibody responses as well as cellular immune responses. Two phase 3 clinical trials are currently underway to determine the efficacy of the Ad26.COV2.S vaccine.
ClinicalTrials.gov Identifier: NCT04436276.
控制全球 COVID-19 大流行将需要开发和部署安全有效的疫苗。
评估 Ad26.COV2.S 疫苗（Janssen/Johnson & Johnson）在人类中的免疫原性，包括 SARS-CoV-2 刺突特异性体液和细胞免疫应答的动力学、幅度和表型。
设计、地点和参与者：2020 年 7 月 29 日至 8 月 7 日期间招募了 25 名参与者，这项第 71 天的中期分析于 2020 年 10 月 3 日完成；对持久性的随访将持续 2 年。这项研究是在马萨诸塞州波士顿的一个单一临床地点进行的，是 Ad26.COV2.S 随机、双盲、安慰剂对照 1 期临床试验的一部分。
参与者随机接受 1 或 2 次肌肉内注射，每次注射 5×1010 个病毒颗粒或 1×1011 个 Ad26.COV2.S 疫苗或安慰剂，于第 1 天和第 57 天（每组 5 名参与者）给药。
体液免疫应答包括免疫后多个时间点的结合和中和抗体应答。细胞免疫应答包括免疫斑点和细胞内细胞因子染色测定，以测量 T 细胞应答。
25 名参与者被随机分配（中位年龄 42 岁；年龄范围 22-52 岁；52%为女性，44%为男性，4%为未分化），所有参与者均完成了第 71 天的中期终点试验。在初次免疫后 8 天，分别有 90%和 25%的疫苗接种者出现快速结合和中和抗体应答。在第 57 天，单次免疫后，100%的疫苗接种者可检测到结合和中和抗体。在第 71 天，接种组的刺突特异性结合抗体的几何平均滴度为 2432 至 5729，中和抗体的几何平均滴度为 242 至 449。诱导了多种抗体亚型、Fc 受体结合特性和抗病毒功能。诱导了 CD4+和 CD8+T 细胞应答。
在这项 1 期研究中，单次接种 Ad26.COV2.S 可诱导快速的结合和中和抗体应答以及细胞免疫应答。目前正在进行两项 3 期临床试验，以确定 Ad26.COV2.S 疫苗的疗效。
ClinicalTrials.gov 标识符：NCT04436276。
