Vaccine development and manufacturing is a highly complex and time-consuming endeavour. Historically we have seen it take between five and 18 years to take basic research and turn that into a usable vaccine.
The R&D process for vaccines differs from the development of conventional drugs: vaccines are intended for use in healthy individuals as a preventive measure whereas conventional drugs are aimed at the treatment of a condition.
And vaccine manufacturing is one of the most challenging industries. Depending on the type of vaccine and preventable disease, manufacturing time can vary considerably from 6 months (e.g. seasonal flu vaccine) to 3 years. 70% of this time will be dedicated to quality control.
Right now, pharmaceutical companies have almost 260 vaccines in research and development globally for a range of diseases, including for COVID-19.