COVID-19 has claimed the lives of about 18 million people. Researchers are working around the clock to better understand, cure, and finally eradicate COVID-19 and the sickness that comes with it. WHO and its partners are dedicated to developing COVID-19 vaccines as quickly as possible while maintaining the highest safety requirements. Vaccines go through several stages of research and testing - clinical trials typically have three phases, the last of which is aimed to examine the product's capacity to protect against disease, known as effectiveness. Each phase evaluates the level of risk. Vaccines have previously been developed through a sequence of steps that can take years to complete. Given the critical need for COVID-19 vaccines, enormous financial investments and scientific collaborations are now transforming vaccine development.