Yours is an investigator initiated trial. You may need to write both. I am not sure what you are referring to.
It is worthwhile to take a look at some trial protocol if you have never. They are very standard, much like filling the blanks. Each trial has its own binder. Borrow a binder from someone read. These are not shared, meaning confidential.

You also need a doctor on board if you are not. You are treating patients.