Excipient Effect on Drug Absorption in Humans

Eligibility Criteria

• 1. Healthy volunteers of all ethnic groups and races.
• 2. Male and females between the ages of 18-64 years old, inclusive.
• 3. Subjects who are willing to avoid ingestion of fruit juices and citrus bioflavonoids, such as grapefruit extract, hesperidin supplement and naringin supplement, for a period extending from one week prior to the initiation of the study until its completion.
• 4. Written informed consent obtained from the subject and ability for subject to comply with the requirements of the study.
• 1. Subjects with extreme obesity (BMI \> 35).
• 2. Subjects who are allergic to fexofenadine or SLS.
• 3. Subjects who have hemoglobin level lower than 12 g/dL.
• 4. Subjects who are pregnant, breastfeeding, or unwilling to practice birth control during participation in the study.
• 5. Subjects with chronic constipation.
• 6. Subjects consuming types of food and supplements with the potential to interfere with the study objectives as judged by the Investigator.
• 7. Subjects taking any drugs, especially known OATP2B1 substrates (aliskiren, atenolol, celiprolol, fexofenadine, rosuvastatin and ticlopidine, etc.) except birth control hormonal medications.
• 8. Subjects with a condition, disease, or abnormality that in the opinion of the Investigator would compromise the safety of the subject or the quality of the data.
• 9. Subjects with any disease affecting or impairing the function of the liver, kidney, or heart.
• 10. Subjects with gastrointestinal disease, gastrointestinal disorder, or gastrointestinal surgery.
• 11. Subjects with known infection with HIV, Hepatitis B or Hepatitis C (as determined by questionnaire, no laboratory diagnostics concerning these diseases will be performed within the present study). Volunteers who are cured of past Hepatitis C infection are eligible to participate with a doctor's approval letter.
• 12. Subjects who are smokers or have smoked in the past year and/or have smoked or ingested THC/marijuana in the past week, or who are unwilling to comply throughout the study period.
• 13. Alcohol use on average \> 2 servings/day or \> 14 servings/wk (Serving size: 12oz beer/4oz wine/2oz hard liquor) in the past week or self-reported binge drinking.
• 14. Subjects who are currently receiving any investigational agent or who have received any investigational agents within a period of 5 half-lives of the agent prior to the initiation of the current study.
• 15. Subjects who have donated whole blood within 8 weeks prior to study initiation or plan to donate blood during the study period.
• 16. Non-English speaking.
• 17. Subjects with abnormal laboratory results at Screening Visit as judged by the Investigator or study physician.