[cixin]

We don't really understand how most of the treatments we have work. We have data, we have in many cases some ideas, but we don't know.

Take Psoriasis as an example, doctors are still prescribing coal tar based treatments. I guess they are ~100 years old. They don't work very well, and people don't really know why they should work at all.

Pretty much all Psoriasis treatments are like this, even the more recent ones. They interfere with some pathway related to the immune system... but we don't really understand why they work.

So we don't really understand "how it all fits together" for current treatments. It's still reasonable to use them if they are relatively safe, and work. Same is true of gene therapies.

Mostly we figure out that things work/are safe through experimentation. Not through totally understanding the system.