You jest (a little) but the sad truth is that these drug companies have the financial incentive to study these types of issues. They pay for themselves if they get more market share. And in any case they are already in for many $100s of millions just to get the drug approved these studies are cheap in comparison.
If they wanted to show a new drug is safer than a generic drug (like in the case of head injury) and their study failed they would just halt and bury the study. Nobody would be the wiser. If it showed a benefit, they would pursue it and publish it (like they did here). Nobody is going to pay to study Plavix anymore so they could engineer the study with subtle biases to show the result they want. So take these types of studies with a grain of - well not salt if you have high blood pressure.
What makes you think I was jesting?
I think that is really what the study meant. “We can’t make money off our old drugs because they’re available as generics, so stop using them and buy our new drugs.”
I am particularly amused by the new studies telling us that aspirin is useless or bad for cardiovascular issues.