Did you actually read that article that spends many pages explaining how there is no good way for a firm to patent a repurposed drug that is working the same way as it worked in a prior indication, but is being used for a new indication where it has the same function - exactly what you’re asserting and what I said is not possible?
If you like, here is a paper from the Vanderbilt law review: https://scholarship.law.vanderbilt.edu/cgi/viewcontent.cgi?a...