Private Equity playershttps://www.bloomberg.com/news/articles/2016-04-29/concordia-said-to-work-with-greenhill-to-seek-buyout-bidders
I think it would actually make more sense if it was TPG that would acquire CXR. Just take a look at their portfolio of investments.
https://www.tpg.com/portfolio
They are heavily into everything related to health; Adare, Aerie, Albireo,etc.
I'm thinking it would make sense for them more than Blackstone or Appolo for that matter.