BioNtech has entered into an alliance[1] with 13 European companies to boost the vaccine production, as well as Chinese Fosun Pharma[2]. The agreement with Pfizer was important for the initial trials and production launch of the vaccine, but it's not binding and BioNtech is free to license the vaccine to other manufacturers (most likely under a different brand name from Comirnaty).

Also, BioNTech has partnered with German Evonik[3] and Merck[4] to accelerate vital lipids production by the second half of 2021.

[1] https://www.wsj.com/articles/biontech-recruits-rivals-to-boo...

[2] https://endpts.com/biontech-teams-up-with-fosun-pharma-to-te...

[3] https://corporate.evonik.com/en/evonik-strengthens-strategic...

[4] https://www.merckgroup.com/en/news/biontech-strategic-partne...