Republicans were proposing that back in 2010 when Trump was still supporting Democrats.
Third, he said he'd leverage the huge volume of the US market in negotiating drug buys.
Drug buys for whom?
Medicare.
The MSNBC hosts were talking over him, so you may not have heard it, but that is his policy.
He also called for medical savings accounts, long a conservative policy idea.
Drug companies have contract with many countries. Some countries get their drugs from the same pharmaceuticals that we do for a lot less. Trump will negotiate with them to get the price for the drugs bat or below the lowest price of any other country. That would save taxpayers 300 billion dollars per year.