Medical Affairs, Novavax Inc, Gaithersburg, Maryland, USA.
Clinical Immunology, Novavax Inc, Gaithersburg, Maryland, Gaithersburg, Maryland.
Expert Rev Vaccines. 2023 Jan-Dec;22(1):620-628. doi: 10.1080/14760584.2023.2232020.
Approximately half of the 13.4 billion COVID-19 vaccine doses administered globally were inactivated or viral vector platforms. The harmonization and optimization of vaccine regimens has become a key focus of policymakers and health-care providers and presents an opportunity to reassess the continued use of pandemic-era vaccines.
Immunological evidence from studies of various homologous and heterologous regimens has been rapidly published; however, interpretation of these data is complicated by the many vaccine types and highly variable participant viral exposure and vaccination histories. Recent studies demonstrate that after primary series doses of inactivated (i.e. BBV152, and BBIBP-CorV), and viral vector (ChAdOx1 nCov-2019) vaccines, a heterologous boost with protein-based NVX-CoV2373 elicits more potent ancestral strain and omicron-specific antibody responses compared to homologous and heterologous inactivated and viral vector boosts.
While mRNA vaccines likely yield similar performance to protein-based heterologous booster doses, the latter offers notable advantages to countries with high uptake of inactivated and viral vector vaccines in terms of transportation and storage logistics and can potentially appeal to vaccine hesitant individuals. Moving forward, vaccine-mediated protection in inactivated and viral vector recipients may be optimized with the use of a heterologous protein-based booster such as NVX-CoV2373.
The Immunogenicity and Safety of Protein-based NVX-CoV2373 as a Heterologous Booster for Inactivated and Viral Vector COVID-19 Vaccines. Inactivated or viral vector primary series following a booster dose with homologous or heterologous inactivated vaccines (i.e., BBV152, BBIBP-CorV), and homologous or heterologous viral vector vaccines (i.e., ChAd-Ox1 nCov-19) induces suboptimal immunogenicity compared to the enhanced immunogenicity of heterologous protein-based vaccine NVX-CoV2373.
在全球接种的 134 亿剂 COVID-19 疫苗中，大约有一半是灭活疫苗或病毒载体平台。疫苗方案的协调和优化已成为政策制定者和医疗保健提供者的关注重点，这为重新评估大流行时期疫苗的持续使用提供了机会。
各种同源和异源方案的免疫研究证据已经迅速发表；然而，由于疫苗类型繁多，参与者的病毒暴露和接种史差异很大，这些数据的解释变得复杂。最近的研究表明，在接种了灭活（即 BBV152 和 BBIBP-CorV）和病毒载体（ChAdOx1 nCov-2019）疫苗的基础系列剂量后，用蛋白基 NVX-CoV2373 进行异源加强免疫会引发更有效的原始株和 omicron 特异性抗体反应，与同源和异源灭活和病毒载体加强免疫相比。
虽然 mRNA 疫苗的性能可能与蛋白基异源加强剂量相似，但对于那些在灭活和病毒载体疫苗接种率较高的国家来说，后者在运输和储存方面具有显著优势，并且可能对疫苗犹豫不决的个体具有吸引力。展望未来，使用 NVX-CoV2373 等异源蛋白基疫苗作为加强针，可能会优化灭活和病毒载体受种者的疫苗介导保护。
基于蛋白的 NVX-CoV2373 作为灭活和病毒载体 COVID-19 疫苗异源加强剂的免疫原性和安全性。与同源或异源灭活疫苗（即 BBV152、BBIBP-CorV）或同源或异源病毒载体疫苗（即 ChAd-Ox1 nCov-19）的同源系列相比，异源蛋白基疫苗 NVX-CoV2373 诱导的免疫原性增强，而后续接种同源或异源灭活疫苗（即 BBV152、BBIBP-CorV）或同源或异源病毒载体疫苗（即 ChAd-Ox1 nCov-19）作为加强针会引发次优的免疫原性。
