Since its outbreak in late 2019, SARS-CoV-2 has infected millions of people
and caused 432, 204 deaths across the globe up to June 14, 2020 (WHO website).
SARS-CoV-2 has a high transmission, prolonged incubation time, and an increased
prevalence of asymptomatic infection. All over the world, the authorities are insisting
on non-pharmaceutical interventions such as social distancing, imposing lockdowns,
social isolation, and provision of personal protective equipment (PPEs) to the hospital
and other essential departments. However, these measures have only slowed down the
virus and cannot prevent rebounds on easing the restrictions. Moreover, the hype about
the off-label use of drugs is on the rise. However, the efficacy and the risk of adverse
effects have yet to be explored in clinical trials. Therefore, the only way to confer
immunity and control the pandemic, the development of vaccines, is currently the
research focus. The genetic sequencing of SARS-Cov-2 was done quickly, only in one
month. To develop vaccines at pandemic speed, the scientific community faces the
challenge of proof of clinical safety and efficacy. Moreover, the previous work is done,
and scientists are utilizing the experience of SAR-CoV and MERS and the technologies
thereof for COVID-19. Several manufacturers have announced their program and
progress on vaccine development. Some vaccines have cleared phase I, and phase II
clinical trials, while few are in phase III.
Keywords: Clinical trials, Coronavirus, COVID-19 vaccines, Group immunity,
Herd immunity, Vaccine candidate.
