Most articles report on only a few companies doing vaccine research. This is the most comprehensive article I’ve found. https://www.nature.com/articles/d41573-020-00073-5
“Although a number of large multinational vaccine developers (such as Janssen, Sanofi, Pfizer and GlaxoSmithKline) have engaged in COVID-19 vaccine development, many of the lead developers are small and/or inexperienced in large-scale vaccine manufacture. So, it will be important to ensure coordination of vaccine manufacturing and supply capability and capacity to meet demand.”
This last point may be a major bottleneck. If there is no deal and close co-ordination between a small Biotech and a Big Pharma who can manufacture the drug, valuable time will be lost.Big Pharma has never put public health interests before its own licensing and patent protection.
https://www.theguardian.com/commentisfree/2020/apr/15/coronavirus-treatment-drug-companies
Estimates for development of a virus are widely said to be 12-18 months.
https://www.theguardian.com/world/2020/apr/19/coronavirus-vaccine-when-will-we-have-one
If this is the time to get a lab proven result, the drug still needs FDA approval (even fast track takes some time), then manufacturing which needs time to source the ingredients, set up the manufacturing infrastructure and then scale it up to produce large volume. All of these steps take time, so the total time could be quite a lot longer than 12-18 months.
In addition, distribution will take time. If a target is 50% of the population to reach a safe level (somewhat less than herd immunity threshold), that’s about 4 billion people. Assuming the drug companies manipulate the supplies behind the scenes and distribute most to Europe and North America first, that’s still 50% of 1 billion.
Here’s a terrific article with interactive timelines showing the potential delays at each step until distribution. https://www.nytimes.com/interactive/2020/04/30/opinion/coronavirus-covid-vaccine.html
Most years, I have to wait for the regular flu vaccine because of distribution delays. Is anybody betting they will be able to get a vaccination in 18 months as predicted?
