Coronavirus disease 2019 (COVID-19) has developed as a pandemic, and it created an outrageous effect on the current healthcare and economic system throughout the globe. To date, there is no appropriate therapeutics or vaccines against the disease. The entire human race is eagerly waiting for the development of new therapeutics or vaccines against severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). Efforts are being taken to develop vaccines at a rapid rate for fighting against the ongoing pandemic situation. Amongst the various vaccines under consideration, some are either in the preclinical stage or in the clinical stages of development (phase-I, -II, and -III). Even, phase-III trials are being conducted for some repurposed vaccines like Bacillus Calmette-Guérin, polio vaccine, and measles-mumps-rubella. We have highlighted the ongoing clinical trial landscape of the COVID-19 as well as repurposed vaccines. An insight into the current status of the available antigenic epitopes for SARS-CoV-2 and different types of vaccine platforms of COVID-19 vaccines has been discussed. These vaccines are highlighted throughout the world by different news agencies. Moreover, ongoing clinical trials for repurposed vaccines for COVID-19 and critical factors associated with the development of COVID-19 vaccines have also been described.

中文翻译：

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正在进行的针对COVID-19大流行的疫苗临床试验。

冠状病毒病2019（COVID-19）已成为大流行病，它对全球当前的医疗保健和经济系统产生了严重影响。迄今为止，还没有针对该疾病的适当疗法或疫苗。整个人类都热切地等待着针对严重急性呼吸系统综合症冠状病毒2（SARS-CoV-2）的新疗法或疫苗的开发。为了与持续的大流行情况作斗争，正在努力快速开发疫苗。在所考虑的各种疫苗中，有些处于临床前阶段或处于临床开发阶段（I，II和-III期）。甚至正在对某些重新定型的疫苗（例如卡介苗-芽孢杆菌，脊髓灰质炎疫苗和麻疹-腮腺炎-风疹）进行III期试验。我们着重介绍了COVID-19以及重组疫苗的持续临床试验前景。讨论了对SARS-CoV-2可用抗原表位的现状以及COVID-19疫苗不同类型疫苗平台的了解。这些疫苗在世界各地被不同的新闻社重点报道。此外，还描述了针对COVID-19的重组疫苗以及与COVID-19疫苗开发相关的关键因素的正在进行的临床试验。