Nobel College Faculty of Health Sciences, Department of Pharmaceutical Sciences, Kathmandu, Nepal.
Department of Medical Laboratory Technology, Janamaitri Foundation Institute of Health Sciences, Lalitpur, Nepal.
J Travel Med. 2022 May 31;29(3). doi: 10.1093/jtm/taab191.
BACKGROUND/OBJECTIVE: Heterologous prime-boost doses of COVID-19 vaccines ('mix-and-match' approach) are being studied to test for the effectiveness of Oxford (AZD1222), Pfizer (BNT162b2), Moderna (mRNA-1273) and Novavax (NVX-CoV2373) vaccines for COVID in 'Com-Cov2 trial' in UK, and that of Oxford and Pfizer vaccines in 'CombivacS trial' in Spain. Later, other heterologous combinations of CoronaVac (DB15806), Janssen (JNJ-78436735), CanSino (AD5-nCOV) and other were also being trialled to explore their effectiveness. Previously, such a strategy was deployed for HIV, Ebola virus, malaria, tuberculosis, influenza and hepatitis B to develop the artificial acquired active immunity. The present review explores the science behind such an approach for candidate COVID-19 vaccines developed using 11 different platforms approved by the World Health Organization.
The candidate vaccines' pharmaceutical parameters (e.g. platforms, number needed to vaccinate and intervals, adjuvanted status, excipients and preservatives added, efficacy and effectiveness, vaccine adverse events, and boosters), and clinical aspects must be analysed for the mix-and-match approach. Results prime-boost trials showed safety, effectiveness, higher systemic reactogenicity, well tolerability with improved immunogenicity, and flexibility profiles for future vaccinations, especially during acute and global shortages, compared to the homologous counterparts.
Still, large controlled trials are warranted to address challenging variants of concerns including Omicron and other, and to generalize the effectiveness of the approach in regular as well as emergency use during vaccine scarcity.
背景/目的：正在研究 COVID-19 疫苗的异源初免-加强剂量（“混合匹配”方法），以测试牛津（AZD1222）、辉瑞（BNT162b2）、莫德纳（mRNA-1273）和诺瓦瓦克斯（NVX-CoV2373）疫苗在英国“Com-Cov2 试验”中的有效性，以及牛津和辉瑞疫苗在西班牙“CombivacS 试验”中的有效性。后来，也在试验其他科兴（DB15806）、强生（JNJ-78436735）、康希诺（AD5-nCOV）和其他冠状病毒疫苗的异源组合，以探索其有效性。此前，这种策略曾用于艾滋病毒、埃博拉病毒、疟疾、结核病、流感和乙型肝炎，以开发人工获得性主动免疫。本综述探讨了使用世界卫生组织批准的 11 种不同平台开发的候选 COVID-19 疫苗背后的科学。
必须分析候选疫苗的药物参数（例如平台、需要接种的人数和间隔、佐剂状态、添加的赋形剂和防腐剂、疗效和有效性、疫苗不良反应以及加强针）和临床方面，以了解混合匹配方法。结果初免-加强试验显示，与同源疫苗相比，该方法具有安全性、有效性、更高的全身反应原性、更好的耐受性和改善的免疫原性，以及未来疫苗接种的灵活性特征，特别是在急性和全球短缺期间。
仍需要进行大规模对照试验，以解决包括奥密克戎在内的令人关注的变异问题，并推广该方法在常规和紧急使用期间在疫苗短缺情况下的有效性。
