Lesinurad Interaction Study With Ranitidine

This study will evaluate the potential effect of ranitidine on the pharmacokinetics of
lesinurad. An earlier study demonstrated an effect on lesinurad PK in the presence of both
calcium-containing and magnesium- and aluminum-containing antacids. The current study will
assess whether raising gastric pH, without the presence of these cations, affects lesinurad
PK and PD under the fasted state. If an impact is seen, then the optional second cohort will
be conducted under the fed state.

Inclusion Criteria:

- body weight ≥ 50 kg (110 lbs) and body mass index ≥ 18 and ≤ 30 kg/m2.

- Screening sUA value ≤ 7.0 mg/dL.

- free of any clinically significant disease that requires a physician's care and/or
would interfere with study evaluations or procedures.

- Subject has no clinically relevant abnormalties in vital signs, ECG, physical
examination or safety laboratory values per the Investigator's judgment.

Exclusion Criteria:

- history or clinical manifestations of significant metabolic, hematological,
pulmonary, cardiovascular, gastrointestinal, neurologic, hepatic renal,urological, or
psychiatric disorders.

- history or suspicion of kidney stones.

- undergone major surgery within 3 months prior to Day 1.

- donated blood or experienced significant blood loss (> 450 mL) within 12 weeks prior
to Day 1 or gave a plasma donation within 4 weeks prior to the Screening visit.

- inadequate venous access or unsuitable veins for repeated venipuncture.