NVSI-06-08 is a potential broad-spectrum recombinant COVID-19 vaccine that integrates the antigens from multiple SARS-CoV-2 strains into a single immunogen. Here, we evaluate the safety and immunogenicity of NVSI-06-08 as a heterologous booster dose in BBIBP-CorV recipients in a randomized, double-blind, controlled, phase 2 trial conducted in the United Arab Emirates (NCT05069129). Three groups of healthy adults over 18 years of age (600 participants per group) who have administered two doses of BBIBP-CorV 4-6-month, 7-9-month and >9-month earlier, respectively, are randomized 1:1 to receive either a homologous booster of BBIBP-CorV or a heterologous booster of NVSI-06-08. The incidence of adverse reactions is low, and the overall safety profile is quite similar between two booster regimens. Both Neutralizing and IgG antibodies elicited by NVSI-06-08 booster are significantly higher than those by BBIBP-CorV booster against not only SARS-CoV-2 prototype strain but also multiple variants of concerns (VOCs). Especially, the neutralizing antibody GMT against Omicron variant induced by heterologous NVSI-06-08 booster reaches 367.67, which is substantially greater than that boosted by BBIBP-CorV (GMT: 45.03). In summary, NVSI-06-08 is safe and immunogenic as a booster dose following two doses of BBIBP-CorV, which is immunogenically superior to the homologous boost with another dose of BBIBP-CorV.

NVSI-06-08 是一种潜在的广谱重组 COVID-19 疫苗，它将来自多个 SARS-CoV-2 毒株的抗原整合到一个免疫原中。在这里，我们在阿拉伯联合酋长国进行的一项随机、双盲、对照 2 期试验 (NCT05069129) 中评估了 NVSI-06-08 作为异源加强剂量在 BBIBP-CorV 接受者中的安全性和免疫原性。三组 18 岁以上的健康成年人（每组 600 名参与者）分别在 4-6 个月、7-9 个月和 >9 个月前施用了两剂 BBIBP-CorV，按 1:1 随机分配接受 BBIBP-CorV 的同源增强剂或 NVSI-06-08 的异源增强剂。不良反应的发生率很低，两种加强方案之间的总体安全性非常相似。NVSI-06-08 加强剂引发的中和和 IgG 抗体均显着高于 BBIBP-CorV 加强剂，不仅针对 SARS-CoV-2 原型菌株，而且针对多种关注点 (VOC) 变体。尤其是异源NVSI-06-08增强剂诱导的Omicron变异体中和抗体GMT达到367.67，大大高于BBIBP-CorV增强剂（GMT：45.03）。总之，NVSI-06-08 是安全的，并且在两次剂量的 BBIBP-CorV 之后作为加强剂量具有免疫原性，这在免疫原性上优于使用另一剂量 BBIBP-CorV 的同源加强剂量。异源NVSI-06-08增强剂诱导的针对Omicron变体的中和抗体GMT达到367.67，大大高于BBIBP-CorV增强剂（GMT：45.03）。总之，NVSI-06-08 是安全的，并且在两次剂量的 BBIBP-CorV 之后作为加强剂量具有免疫原性，这在免疫原性上优于使用另一剂量 BBIBP-CorV 的同源加强剂量。异源NVSI-06-08增强剂诱导的针对Omicron变体的中和抗体GMT达到367.67，大大高于BBIBP-CorV增强剂（GMT：45.03）。总之，NVSI-06-08 是安全的，并且在两次剂量的 BBIBP-CorV 之后作为加强剂量具有免疫原性，这在免疫原性上优于使用另一剂量 BBIBP-CorV 的同源加强剂量。