DDI Study With Multiple-dose LX4211 and Single Dose Digoxin

Inclusion Criteria: * Adult subjects ≥18 to ≤55 years of age * Vital signs at Screening in the following ranges: systolic blood pressure, 90-140 mmHg; diastolic blood pressure, 50-90 mmHg; heart rate, 45-100 bpm * Body mass index (BMI) ≥18 and ≤32 kg/sq m * Willing and able to provide written informed consent Exclusion Criteria: * Presence of clinically significant physical, laboratory, or ECG findings that, in the opinion of the Investigator and/or Sponsor, may interfere with any aspect of study conduct or interpretation of results * History of clinically significant arrhythmias * History of cardiac arrhythmias or palpitations associated with presyncope, syncope, or a family history of sudden cardiac death * Use of any medications or supplements/supratherapeutic doses of vitamins within 14 days prior to the first dose administration and throughout the duration of the study * Receipt of any investigational agent or study drug within 30 days prior to Screening * Receipt of any protein- or antibody-based therapeutic agents within 3 months prior to Screening * Prior exposure to LX4211 * Use of tobacco, smoking cessation products, or products containing nicotine within 3 months prior to Screening and for the duration of the study * History of any serious adverse reaction or hypersensitivity to any inactive component of LX4211 or digoxin * Existence of any surgical or medical condition that might interfere with the absorption, distribution, metabolism, or excretion of LX4211 or digoxin * History of any major surgery within 6 months or anticipated surgery prior to Day 1 * History of any clinically significant hypoglycemia or hyperglycemia * History of renal disease, or significantly abnormal kidney function test at Screening * History of hepatic disease, or significantly abnormal liver function tests at Screening * History of any clinically relevant psychiatric, renal, hepatic, pancreatic, endocrine, cardiovascular, neurological, hematological, or GI abnormality * History of any active infection within 14 days prior to Day 1 * History of alcohol or substance abuse within 2 years prior to Screening * Positive hepatitis panel * Donation or loss of \>500 mL of blood or blood product within 3 months prior to Screening * Women who are breastfeeding or are planning to become pregnant during the study, or women who have a positive serum pregnancy test * Positive urine glucose at Screening * Positive urine screen for drugs of abuse and cotinine at Screening, Day -1, or Day 13 * Inability or difficulty swallowing whole tablets * Unable or unwilling to cooperate with the Investigator for any reason