No worries, no groundup mice within remicade
Most medications we take (like mesalamine or tylenol) are raw elements compounded together. It's much like we do, ourselves when we bake a cake. Raw elements are mixed together, and a process like heating or adding acids produces the medicine. They refine the medicine to remove impurities and isolate just the desired substance.
Biologics are entirely different in manufacture, and are far too complex in chemical structure to be compounded (as within the prior example). Instead, we reprogram living cells to manufacture the protein we call remicade/humira for us. If you think about
how a cold/flu virus works, it enters a living cell and reprograms the cell to produce more viruses in mass. That's exactly what is done except by people.
There's a couple cell lineages, some are bacterial in origin, one was originally a hamster cell (entyvio) and another was originally a mouse cell (remicade). They take a single cell, remove the cell interior and reprogrammed it to do something entirely different than it would've done. That genetically engineered cell's purpose is to now produce lots of remicade/entyvio proteins. These cell lineages have been used for decades for research, and far divorced from the original animal from which they came. They have large vats temperature controlled, and surrounded by nutrients with many of these cells suspended within it. Periodically they extract the proteins produced from the cells, remove impurities, and the medication is acquired.
https://www.sciencechannel.com/tv-shows/how-its-made/videos/how-biologic-medicines-are-madehttps://weekly.biotechprimer.com/biomanufacturing-how-biologics-are-made/