Wait for them to get out of patent? The average remaining patent term for newly approved drugs is 10-12 years. So drugs approved in 2008 will mostly be coming out of patent this year.

All this stuff you here about “evergreening” is entirely the result of gaming the FDA approval practices. Patent law is categorical: once you make a thing publicly available, that thing is prior art not just for the patent you file to cover it, but every invention embodied in the thing. So once the first set of patents expires on the thing, that thing itself is in the public domain. You can’t bring that specific thing out of the public domain by making incremental improvements, etc.