The purpose of this study is to determine the effects of LX4211 and metformin on each other when given at the same time as single doses to healthy human subjects.

Inclusion Criteria:

• Adults ≥18 to ≤55 years of age. Females must be of non-childbearing potential.
• Body mass index (BMI)≥18 to ≤35 kg/sq m
• Able to provide written consent
• Vital signs within sponsor-defined ranges

Exclusion Criteria:

• Use of any medication, including any prescription, over-the-counter, herbal tea, or other supplements within 5 days of dosing
• No investigational agent or study treatment within 30 days prior to Day 1.
• No protein or antibody-based therapeutic agents within 3 months prior to screening
• Use of any tobacco product
• History of bariatric surgery or any gastrointestinal surgery that may induce malabsorption
• History of any major surgery within 6 months prior to screening
• History of any serious adverse reaction or hypersensitivity to metformin or LX4211.
• History of renal disease or significantly abnormal kidney function test
• History of hepatic disease or significantly abnormal liver function test
• History of any active infection within 30 days prior to Day 1
• History of any surgical or medical condition or clinically significant laboratory or physical finding
• Positive urine glucose at Screening
• Use of drugs or alcohol