It seems like this is EXACTLY what is being tackled by the Clinical Trials working group. I searched for this information by using “cohort” and “cohort_definition” where I should’ve instead started with “Clinical Trials” as my search criteria. Leaving this forum post here just in case others go down this path and need a few breadcrumbs!
This post has been the most helpful as it contains links to the current proposal for modification of the CDM by the working group: