Study ended after diabetes development plan review. .

Determine the effect of treatment with INCB019602 administered as an add-on to stable dose metformin therapy in type 2 diabetic subjects on safety and glycemic control.

Inclusion Criteria:

• Established diagnosis of T2D
• Currently taking metformin monotherapy at a stable dose level
• FPG between 150 and 270 mg/dL

Exclusion Criteria:

• History or clinical manifestations of renal impairment
• Hyperglycemia > 270 mg/dL
• Receiving thiazolidenediones, Exenatide or sulfonylureas within 90 days prior to screening
• Prior use of Acipimox which is known under the name Olbetam within 90 days prior to screening.
• Diagnosed major depression within the last 2 years requiring hospitalization
• History of chronic insulin therapy for glycemic control