Pancreatic hormone (7)
I believe the answer is:
insulin
'pancreatic hormone' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for insulin that I've seen before include "Hormone or medication controlling body's sugar level" , "Hormone that regulates the storage of glycogen in the liver" , "Hormone for treating diabetes" , "Hormone controlling sugar supply" , "Treatment for diabetic" .)