Why do we need to understand the importance of an incident reports?

Me with this i need to get the answer quickly.

Adouble-blinded trial for a new indication is conducted under an ind comparing two (2) marketed drugs, at twice the approved prescribed doses. on day 2, subject 603 had difficulty breathing. although it was life-threatening initially, subject 603 was treated and discharged directly from the emergency department after complete recovery. on day 5, subject 20 had a headache, which led to hospitalization and required blood pressure lowering medications. these episodes cannot be explained on the basis of the pharmacological property of either drug or the subjects' medical histories. the investigator would submit an sae report for

1. controls how much sugar is in the blood pancreas 2. controls the other glands pituitary gland 3. manufactured by the brain to relieve pain thyroid 4. gland that regulates the body's energy levels endorphins