Where are you getting the idea that we can't?
Hundreds of millions of doses of the Pfizer and Moderna vaccines have already been made. Pfizer expects to make 2 billion doses this year.
1. https://theconversation.com/how-patent-laws-get-in-the-way-o...
2. https://www.thedailybeast.com/heres-why-it-will-be-hard-to-r...
https://www.novartis.com/news/media-releases/novartis-signs-...
> Novartis announced today that it has signed an initial agreement to leverage its manufacturing capacity and capabilities in order to address the COVID-19 pandemic by supporting the production of the Pfizer-BioNTech COVID-19 Vaccine. The agreement will see Novartis utilizing its aseptic manufacturing facilities at its site in Stein, Switzerland.
https://www.merck.com/stories/why-were-excited-to-partner-on...
> On March 2, we announced a partnership with Johnson & Johnson to expand manufacturing capacity and supply of its COVID-19 vaccine. Under the Biomedical Advanced Research and Development Authority (BARDA) agreement, our company is adapting and making available some of our existing manufacturing sites to accelerate manufacturing efforts for the vaccine and enable more timely delivery and administration.
https://investors.modernatx.com/news-releases/news-release-d...
> Under the terms of the agreement, the companies plan to establish manufacturing suites at Lonza’s facilities in the United States and Switzerland for the manufacture of mRNA-1273 at both sites. Technology transfer is expected to begin in June 2020, and the companies intend to manufacture the first batches of mRNA-1273 at Lonza U.S. in July 2020.
https://www.astrazeneca.com/media-centre/press-releases/2021...
> AstraZeneca and IDT Biologika also intend to strengthen Europe’s vaccine manufacturing capability with a joint investment to build large additional drug substance capacity for the future. Details of the agreement are to be finalised. Both companies plan to invest in capacity expansion at IDT Biologika’s production site in Dessau, Germany to build up to five 2,000-litre bioreactors capable of making tens of millions of doses per month of AstraZeneca’s COVID-19 vaccine. The new assets are estimated to be operational by the end of 2022.