A national health insurance system is not the opposite of profits for pharmaceutical companies. More importantly, the outrageous profits of pharmaceutical companies lead to many inefficiencies in the system. You point out one where they give rebates to cover copays.
But drug companies still have the incorrect incentive to “push” expensive drug therapy solutions for many conditions where a less expensive option exists.
Huff Post conducted an expose on Johnson & Johnson several years ago. They had effectively marketed blockbuster drugs which were less effective than the generics they replaced. http://highline.huffingtonpost.com/miracleindustry/americas-most-admired-lawbreaker/
This is not to say that the price for drugs to treat hemophilia are being driven to unfairly high margins. it only means that patients need an advocate whose profits aren’t based on a percentage of their costs.