Excipient Effect on Drug Absorption in Humans

The Effect of Sodium Lauryl Sulfate on the Oral Absorption of Fexofenadine in Humans

The purpose of this study is to determine if sodium lauryl sulfate (SLS), a non-drug ingredient commonly added in drug products, affect absorption of drugs that are given together with the ingredient. Investigators want to find out if drug absorption is different in people taking the drug alone compared to people taking the drug with low and high amounts of sodium lauryl sulfate at the same time.

Study Overview

• Status: Completed
• Conditions: The Impact of Excipients on Drug Absorption
• Intervention / Treatment: Drug: Fexofenadine Hydrochloride without sodium lauryl sulfate; Drug: Fexofenadine Hydrochloride with sodium lauryl sulfate

Detailed Description

This is a single-center, randomized, double-blind, 3-period crossover trial. Participants will be randomized to receive a Control capsule (fexofenadine single agent) under Treatment Arm 1 or a Test 1 capsule (fexofenadine and 3 mg SLS) under Treatment Arm 2 or Test 2 capsule (fexofenadine and 30 mg SLS) under Treatment Arm 3. Investigators will assess the effect of SLS on the absorption of fexofenadine by measuring SLS and fexofenadine concentrations in plasma and stool samples and determine the change in AUC (area under the curve), Cmax and other pharmacokinetic parameters, between Treatment Arms 2 or 3 and Treatment Arm 1.

• Study Type: Interventional
• Enrollment (Actual): 12
• Phase: Early Phase 1

Contacts and Locations

Study Locations

• United States
  • California
    • San Francisco, California, United States, 94143
      • Ucsf Ctsi Crc

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 64 years (Adult)
• Accepts Healthy Volunteers: Yes

Description

Inclusion 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.

Exclusion Criteria:

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.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: Double

Number of Arms

3

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Fexofenadine without SLS; Participants will be administered by mouth with a capsule containing 120 mg fexofenadine hydrochloride and 101 mg microcrystalline cellulose	Drug: Fexofenadine Hydrochloride without sodium lauryl sulfate; without sodium lauryl sulfate; Other Names: Allegra
Experimental: Fexofenadine and 3 mg SLS; Participants will be administered by mouth with a capsule containing 120 mg fexofenadine hydrochloride, 3 mg SLS and 101 mg microcrystalline cellulose	Drug: Fexofenadine Hydrochloride with sodium lauryl sulfate; with sodium lauryl sulfate; Other Names: Allegra
Experimental: Fexofenadine and 30 mg SLS; Participants will be administered by mouth with a capsule containing 120 mg fexofenadine hydrochloride, 30 mg SLS and 101 mg microcrystalline cellulose	Drug: Fexofenadine Hydrochloride with sodium lauryl sulfate; with sodium lauryl sulfate; Other Names: Allegra

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Area under the plasma concentration versus time curve (AUC) of Fexofenadine	To determine whether SLS decreases the fexofenadine area under the curve (AUC) between Fexofenadine + 3 mg SLS or Fexofenadine + 30 mg SLS and Fexofenadine only.	0-48 hours
Maximum Plasma Concentration (Cmax) of Fexofenadine	To determine whether SLS decreases the fexofenadine Cmax between Fexofenadine + 3 mg SLS or Fexofenadine + 30 mg SLS and Fexofenadine only.	0-48 hours

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Sodium lauryl sulfate plasma concentration	To determine plasma SLS concentration in order to understand the absorption of SLS in humans	0-48 hours
Fexofenadine stool amount	To determine stool amount of fexofenadine and compare between the fexofenadine only arm to the 3 mg SLS and the 30 mg SLS arm.	0-48 hours
Sodium lauryl sulfate stool amount	To determine stool amount of sodium lauryl sulfate and compare between the fexofenadine only arm to the 3 mg SLS and the 30 mg SLS arm.	0-48 hours

Collaborators and Investigators

• Sponsor: University of California, San Francisco
• Collaborators: Food and Drug Administration (FDA)
• Investigators: Principal Investigator: Katherine Yang, PharmD, MPH, University of California, San Francisco

Study record dates

Study Major Dates

• Study Start (Actual): January 31, 2023
• Primary Completion (Actual): June 18, 2025
• Study Completion (Actual): August 18, 2025

Study Registration Dates

• First Submitted: August 26, 2020
• First Submitted That Met QC Criteria: August 26, 2020
• First Posted (Actual): September 1, 2020

Study Record Updates

• Last Update Posted (Estimated): November 18, 2025
• Last Update Submitted That Met QC Criteria: November 14, 2025
• Last Verified: November 1, 2025

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Sulfur Compounds; Organic Chemicals; Lipids; Alcohols; Alkanesulfonates; Alkanesulfonic Acids; Sulfonic Acids; Sulfur Acids; Fatty Alcohols; Dodecanol; fexofenadine; Sodium Dodecyl Sulfate
• Other Study ID Numbers: 20-31871

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: Each participant's data will be de-identified before it is shared with others who meet specified access criteria.
• IPD Sharing Time Frame: Once after publication
• IPD Sharing Access Criteria: De-identified specimens may be shared with other researchers so they can use them for, but not limited to, genomic, epigenetic, metabolomic, proteomic and transcriptomic follow-up studies.

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: Yes
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No