This is a Phase 1, open-label, fixed-sequence, 3-period, 2-way drug interaction study designed to assess the pharmacokinetics, pharmacodynamics, safety, and tolerability of LC350189 and Naproxen when administered alone and in combination in healthy subjects.

Inclusion Criteria:

• The subject is male or female 18 to 50 years of age, inclusive.
• The subject has a body mass index 18 to 32 kg/m2, inclusive, at screening.
• The subject is judged by the investigator to be in good general health, as determined by medical history, clinical laboratory assessments, vital sign measurements, 12 lead electrocardiogram (ECG) results, and physical examination findings at screening.
• The subject agrees to comply with all protocol requirements.
• The subject is able to provide written informed consent.

Exclusion Criteria:

• The subject has a medical history with any issues affecting absorption or metabolism, as judged by the investigator.
• The subject has a positive test result for hepatitis B surface antigen, hepatitis C virus antibody, or human immunodeficiency virus types 1 or 2 antibodies at screening.
• The subject has an estimated glomerular filtration rate (eGFR) of <90 (mL/min)/1.73 m2.
• The subject has used any prescription (excluding hormonal birth control and hormone replacement therapy) or over the counter medications (except paracetamol [up to 2 g per day]), including herbal or nutritional supplements, within 14 days before the first dose of study drug or throughout the study.
• The subject has consumed grapefruit or grapefruit juice, Seville orange or Seville orange containing products (eg, marmalade), or caffeine- or xanthine containing products within 48 hours before the first dose of study drug or throughout the study.
• The subject is a smoker or has used nicotine or nicotine-containing products (eg, snuff, nicotine patch, nicotine chewing gum, mock cigarettes, or inhalers) within 6 months before the first dose of study drug.
• The subject has a history of alcohol abuse or drug addiction within the last year or excessive alcohol consumption (regular alcohol intake >21 units per week for male subjects and >14 units of alcohol per week for female subjects) (1 unit is equal to approximately ½ pint [200 mL] of beer, 1 small glass [100 mL] of wine, or 1 measure [25 mL] of spirits).
• The subject has a positive test result for drugs of abuse, alcohol, or cotinine (indicating active current smoking) at screening or before the first dose of study drug.