COVID-19 vaccine development and the way forward.

ABSTRACT

The whole globe is reeling under the COVID-19 pandemic now. With the scale and severity of infection, number of deaths and lack of any definite therapeutic armamentarium, the vaccine development has been accelerated at a never-before pace. A wide variety of vaccine technologies and platforms are being attempted. Out of the over 108 efforts, 100 are in preclinical and eight in Phase 1 or 2 trial stage. While the availability of newer technologies has facilitated development, there are several challenges on the way including limited understanding of the pathophysiology, targeting humoral or mucosal immunity, lack of suitable animal model, poor success of human severe acute respiratory syndrome/Middle East Respiratory Syndrome vaccines, limited efficacy of influenza vaccines, and immune exaggeration with animal coronavirus vaccines. With the current scenario with political, funding, research, and regulatory supports, if everything sails through smoothly, the successful vaccine is expected in 12-18 months. Modestly efficacious vaccine may be also a good achievement.