I believe so too, it would also simply require too many good people in labs all around te world to not say anything about it. I find that highly unlikely.
Try looking up how many whistleblowers are out there that you've never heard of.
That is one example that was interpreted by you to be valid for all other cases?
Seeing your other comments I think you highly trust the medical system.
Never trust blindly my friend.
Please give an example of a cure that has been hidden by pharma. I'm all ears.
Yet I cannot afford the USD $200,000 price tag for Gilead's cure.