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