Randomisation Eligible consenting patients will be randomly allocated into 2 groups to receive either; Bydureon 2mg subcutaneous injection once weekly for 48 weeks n=30, or Bydureon placebo subcutaneous injection once weekly for 48 weeks n=30. Randomisation lists will be sufficiently long to enable continued randomisation should any patients drop out within the first 12 weeks of the study (prior to the first follow up visit).