Current progress and challenges in the design and development of a successful COVID-19 vaccine

The coronavirus disease 2019 (COVID-19) pandemic, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is still a worldwide concern, with little to no sign of a decreasing trend. There is a general consensus that normal life will be hampered until a safe and effective vaccine strategy is available and globally administered. Numerous countries have accelerated the clinical trials process for the development of a successful COVID-19 treatment, with over 200 candidates presently available for testing against SARS-CoV-2. Here, we provide an overview of the COVID-19 vaccine candidates currently in development, discuss the scientific and practical challenges associated with COVID-19 vaccine design, and share the potential strategies that could be exploited for vaccine design success.