Pfizer is working to advance their own potential antiviral therapies and is engaged with BioNTech, German biotech company, on a potential mRNA coronavirus vaccine. The companies are scaling up production to potentially produce millions of vaccine doses by the end of the year — and hundreds of millions in 2021 — depending on how well their vaccine works and the course of regulatory approval.  BioNTech is working on a number of vaccine candidates using mRNA platforms, and hopes to begin human trials this month.