The SARs-CoV-2 (COVID-19) virus, which was first identified in December 2019, in Wuhan China, is a respiratory virus that induces respiratory distress and a systemic inflammatory reaction in the vasculature mediated by a cytokine storm. Currently, 72 million people have been infected with 1.6 million deaths giving a mortality rate of 2.2% despite the best post-infective medical intervention available. Due to the rapid spread of the COVID virus and the worldwide pandemic that has developed, the rush for the development of a vaccine has become a priority amongst health care official’s world-wide. In this review, we discuss what is currently known about the mechanism of action, efficacy, and toxicity of three of the most promising vaccines mRNA-1273 (Moderna), BNT162b2 (Pfizer/BioNtech), ChAdOx1 nCoV-19 (Astrazenac/Oxford), and rAd26)/rAd5 (Sputnik V) against COVID-19.