■SARS-CoV-2Omicron变体已成为主要的SARS-CoV-2变体,并表现出对当前COVID-19疫苗的免疫逃逸,需要进一步的促进策略。
■我们进行了非随机化,开放标签和平行对照的4期试验,以评估肌内腺病毒载体疫苗(Ad5-nCoV)加强疫苗接种的免疫反应的大小和寿命,雾化Ad5-nCoV,重组蛋白亚单位疫苗(ZF2001)或同源灭活疫苗(CoronaVac),用于接受两剂灭活COVID-19疫苗的人。
■雾化的Ad5-nCoV在所有助推器中对Omicron变体和IFNgT细胞反应诱导了最强大和持久的中和活性,有明显的粘膜免疫反应。在接种后第14天,在用雾化Ad5-nCoV加强的受试者中基本上产生了SARS-CoV-2特异性粘膜IgA应答。在第6个月,与接受其他增强剂的参与者相比,使用雾化Ad5-nCoV增强的参与者的OmicronBA.4/5特异性中和抗体的中位滴度和血清转化率明显更高。
■我们的发现表明,雾化的Ad5-nCoV可能会提供一种有效的替代方案,以响应OmicronBA.4/5变体的传播。
■https://www.chictr.org.cn/showproj.html?proj=152729,标识符ChiCTR2200057278。
The SARS-CoV-2 Omicron variant has become the dominant SARS-CoV-2 variant and exhibits immune escape to current COVID-19 vaccines, the further boosting strategies are required.
We have conducted a non-randomized, open-label and parallel-controlled phase 4 trial to evaluate the magnitude and longevity of immune responses to booster vaccination with intramuscular adenovirus vectored vaccine (Ad5-nCoV),
aerosolized Ad5-nCoV, a recombinant protein subunit vaccine (ZF2001) or homologous inactivated vaccine (CoronaVac) in those who received two doses of inactivated COVID-19 vaccines.
The
aerosolized Ad5-nCoV induced the most robust and long-lasting neutralizing activity against Omicron variant and IFNg T-cell response among all the boosters, with a distinct mucosal immune response. SARS-CoV-2-specific mucosal IgA response was substantially generated in subjects boosted with the
aerosolized Ad5-nCoV at day 14 post-vaccination. At month 6, participants boosted with the
aerosolized Ad5-nCoV had remarkably higher median titer and seroconversion of the Omicron BA.4/5-specific neutralizing antibody than those who received other boosters.
Our findings suggest that
aerosolized Ad5-nCoV may provide an efficient alternative in response to the spread of the Omicron BA.4/5 variant.
https://www.chictr.org.cn/showproj.html?proj=152729, identifier ChiCTR2200057278.