The protocol is the thorough, written description of the objective(s), design, methodology, statistical consideration, and organization of a trial. The protocol may also contain relevant scientific background to justify the trial.

The sponsor may develop a standardized template for investigators to ensure the protocol includes the required content. Changes to the protocol can be requested as needed to ensure compliance is possible.

Clinical trial protocols must meet a standard that maintains the principles of Good Clinical Practice. The protocol is one of the documents submitted to the IRB to obtain approval for the trial. Any changes must also be approved by the IRB as the trial progresses.

Source: Food and Drug Administration (FDA). (2020, May). E6(R2) Good Clinical Practice: Integrated Addendum to ICH E6(R1). US Department of Health & Human Services.