[s1artibartfast]

Randomization is independent from blinding. Open label studies can be either randomized or not, and controlled or not.

The FDA will usually push for blinding if possible (sometimes it is not). They will also usually push for a randomization zed control with standard of care. They way the FDA views it (and I agree), is that control patients are not harmed because they are still getting the same care they would outside of the trial.

It is usually unethical to have a treatment free arm. However, this has its own problem, where if you keep using equivalence comparisons, the end of the chain might not actually be any better