If you are taking any cholesterol-lowering drugs, these drugs must be discontinued on the day prior to the Pre-Treatment Visit (Week -4) and for the duration of the study. At Visit 1 (Week 0) you will be assigned to DIO-902 or DIO-902 placebo and to either atorvastatin or atorvastatin placebo. You will continue to take the assigned drug until Study Visit 4 (Week 8). At Study Visit 4 (Week 8) all patients will begin taking atorvastatin through the remainder of the study. Your DIO-902 or DIO-902 placebo assignment will remain the same. Atorvastatin tablets will be supplied to you until Study Visit 6 (Week 16). At this visit you will be given a prescription for a 28 day supply of atorvastatin 10mg.day to last until Study Visit 7 (Week 20).