Thank you for entertaining my curiosity! I have been meaning to educate myself on this but don't know anybody in my circle who is knowledgeable in this field.
In another comment I said that if the area of biology/microbiology etc were the size of the surface of our sun, the area of our knowledge in those subjects would be perhaps a square millimeter.
And if you think that’s bad, don’t get me started on higher level areas like neurology.
We can try to simulate the interaction between a drug and a protein, but most of the time the data to say what the downstream effects (if any) are simply does not exist. This is further complicated by the fact that these downstream effects can be extremely varied depending on both the tissue/disease you are targeting and the person you are treating.
Of course we are always generating more data from more diverse populations and more conditions, but there is a very very long way to being able to simulate drug trials like this.