One of the huge problems with making generic drugs is that you need to demonstrate that your drug does the same thing as the real deal, which isn't as expensive as phase I, II, and III trials for bringing a completely new product to market, but it isn't cheap, fast, or easy. Likewise, setting up proper facilities to manufacture your product isn't cheap, either.

https://www.fda.gov/drugs/news-events-human-drugs/generic-dr...