Efficacy and safety are intertwined. Safety can sometimes only be evaluated in the context of efficacy. For example, you wouldn't amputate a healthy arm. But fo

Efficacy and safety are intertwined. Safety can sometimes only be evaluated in the context of efficacy. For example, you wouldn't amputate a healthy arm. But for a gangrenous one, it may be the only option. For establishing efficacy and safety, trials are the only process that works. Nobody can predict the effects of drugs because the current understanding of biology is very incomplete. Thalidomide [1] shows the wisdom of the current approach. [1]: https://en.m.wikipedia.org/wiki/Thalidomide https://en.m.wikipedia.org/wiki/Thalidomide