This protocol is intended to compare the effects of both a solid (tablet) and liquid oral dosage form of LX4211 in subjects with type 2 diabetes mellitus.

Inclusion Criteria:

• Adults aged 18 to 65 years of age
• Males and females of non-childbearing potential
• Diagnosis of type 2 diabetes mellitus for at least 6 months prior to screening
• Fasting plasma glucose ≤240 mg/dL
• Body mass index <42 kg/sq m
• HbA1c of 7-11%
• C-peptide of ≥1.0 ng/mL
• Ability to provide written informed consent

Exclusion Criteria:

• History of type 1 diabetes mellitus, diabetic ketoacidosis, hyperosmolar nonketonic syndrome, incontinence, or nocturia
• Current use of any blood glucose-lowering agent other than metformin
• Exposure to insulin, thiazide, or loop diuretics within 4 weeks prior to screening
• History of HIV, Hepatitis B, or Hepatitis C
• Surgery within 6 months of screening
• Donation or loss of >400 mL of blood or blood product within 8 weeks prior to start of study
• Use of proteins or antibodies within 12 weeks prior to screening. (Flu shots are allowed.)
• Exposure to any investigational agent or participation in an investigational trial within 30 days of the start of the study
• History of drug or alcohol abuse within 12 months prior to screening.