And to add, a clinical trial can be thought of as just one step to establish evidence for efficacy and safety. Because if you really want to prove that it work

And to add, a clinical trial can be thought of as just one step to establish evidence for efficacy and safety. Because if you really want to prove that it works and is safe, you have to give it to a lot of people, all of whom have different health conditions. To establish that, you would ideally give it to everyone with the disease of interest. But you can't test a drug on the entire world, so.... you only find so much in a clinical trial.