Soldatov Alexander A, Kryuchkov Nickolay A, Gorenkov Dmitry V, Avdeeva Zhanna I, Svitich Oxana A, Soshnikov Sergey
Scientific Centre for Expert Evaluation of Medicinal Products of the Ministry of Health of the Russian Federation, 8/2 Petrovsky Boulevard, Moscow 127051, Russia.
CEG PharmDev DOO, 21000 Novi Sad, Serbia.
Vaccines (Basel). 2025 Jul 24;13(8):789. doi: 10.3390/vaccines13080789.
The COVID-19 pandemic accelerated the rapid development and distribution of various vaccine platforms, resulting in a significant reduction in disease severity, hospitalizations, and mortality. However, persistent challenges remain concerning the durability and breadth of vaccine-induced protection, especially in the face of emerging SARS-CoV-2 variants. This review aimed to evaluate the factors influencing the immunogenicity and effectiveness of COVID-19 vaccines to inform future vaccine advancement strategies. A narrative review with systematic approach was conducted following PRISMA guidelines for narrative review. Literature was sourced from databases including PubMed, Embase, and Web of Science for studies published between December 2019 and May 2025. Encompassed studies assessed vaccine efficacy, immunogenicity, and safety across various populations and vaccine platforms. Data were collected qualitatively, with quantitative data from reviews highlighted where available. We have uncovered a decline in vaccine efficacy over time and weakened protection against novel variants such as Delta and Omicron. Booster doses, specifically heterologous regimens, improved immunogenicity and increased protection. Vaccine-induced neutralizing antibody titers have been found to correlate with clinical protection, although the long-term correlates of immunity remain poorly defined. The induction of IgG4 antibodies after repeated mRNA vaccinations raised concerns about potential modulation of the immune response. COVID-19 vaccines have contributed significantly to pandemic control; however, their efficacy is limited by the evolution of the virus and declining immunity. Forthcoming vaccine strategies should focus on broad-spectrum, variant-adapted formulations and defining robust comparisons of protection. Recognizing the immunological basis of vaccine response, including the role of specific antibody subclasses, is fundamental for optimizing long-term protection.
新冠疫情加速了各种疫苗平台的快速研发和分发，导致疾病严重程度、住院率和死亡率显著降低。然而，疫苗诱导的保护作用的持久性和广度仍然存在持续挑战，尤其是面对新出现的严重急性呼吸综合征冠状病毒2（SARS-CoV-2）变体时。本综述旨在评估影响新冠疫苗免疫原性和有效性的因素，为未来疫苗研发策略提供参考。按照系统评价和荟萃分析扩展版（PRISMA）指南进行了叙述性综述。文献来源于包括PubMed、Embase和Web of Science在内的数据库，检索2019年12月至2025年5月发表的研究。纳入的研究评估了不同人群和疫苗平台的疫苗效力、免疫原性和安全性。数据采用定性收集，如有可用，突出显示综述中的定量数据。我们发现疫苗效力随时间下降，对德尔塔和奥密克戎等新变体的保护作用减弱。加强剂量，特别是异源方案，提高了免疫原性并增强了保护作用。尽管免疫的长期相关因素仍不清楚，但已发现疫苗诱导的中和抗体滴度与临床保护相关。重复接种信使核糖核酸（mRNA）疫苗后诱导产生的免疫球蛋白G4（IgG4）抗体引发了对免疫反应潜在调节的担忧。新冠疫苗对疫情防控做出了重大贡献；然而，其效力受到病毒进化和免疫力下降的限制。未来的疫苗策略应侧重于广谱、适应变体的配方，并确定强有力的保护作用比较。认识到疫苗反应的免疫学基础，包括特定抗体亚类的作用，是优化长期保护的基础。
