You can search the US government's website in general here:
https://clinicaltrials.gov/

You can also filter by specific criteria. For example, specifying "Pancreatic Cancer" as the Condition/Disease, "Keytruda" (Pembrolizumab) as the Intervention/Treatment, and "Recruiting" in the "Looking for participants" checkbox under "Study Status" returns a list of 37 studies (as of 11/6/2023):
https://clinicaltrials.gov/search?intr=keytruda&cond=Pancreatic%20Cancer&aggFilters=status:rec

You'll probably need to refine the filters even further to get the right type and stage of pancreatic cancer, the trial phase you want, the right locations and eligibility criteria, etc., but hopefully this gets you in the ballpark.

It can also be useful to select the "with results" checkbox if you're looking at studies that have already closed and want to see how the study worked out.