in october 2001, amylin received an approvable letter for symlin from the fda, requiring additional clinical data addressing concerns of severe hypoglycemia in type 1 diabetics for approval. in december 2003, the fda issued a second approvable letter requesting further clinical data to identify a patient population and method of use for symlin where there is no increased risk of significant hypoglycemia or where there is an added benefit that clearly counterbalances any potential for increases in episodes of hypoglycemia. in march 2005, symlin was approved by the fda for use in diabetics who have difficulty maintaining glycemic control.