The Impact of Excipients on Drug AbsorptionEarly Phase 1NCT04534153
Excipient Effect on Drug Absorption in Humans
A Early Phase 1 study testing Fexofenadine Hydrochloride without sodium lauryl sulfate and Fexofenadine Hydrochloride with sodium lauryl sulfate in people with The Impact of Excipients on Drug Absorption, run by University of California, San Francisco at 1 site in United States.
Trial summary
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. Read more about this study
- Who is it for?
- Ages 18 to 64 yearsHealthy volunteers can take part
- Conditions the study is for
- The Impact of Excipients on Drug Absorption
- What is being tested?
- Fexofenadine Hydrochloride without sodium lauryl sulfate and Fexofenadine Hydrochloride with sodium lauryl sulfate
- Type of treatment
- Pill or oral medicine
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 12 participants
- Where
- 1 siteUnited States
- Study dates
- 31 Jan 2023to 18 Aug 2025
- Phase
- Early Phase 1
- Are there results?
- None posted in the registry
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 to 64 years
- All sexes
- Healthy volunteers accepted
- Adult
Who may be able to join
- Healthy volunteers of all ethnic groups and races.
- Male and females between the ages of 18-64 years old, inclusive.
- 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.
- Written informed consent obtained from the subject and ability for subject to comply with the requirements of the study.
Who cannot join
- Subjects with extreme obesity (BMI > 35).
- Subjects who are allergic to fexofenadine or SLS.
- Subjects who have hemoglobin level lower than 12 g/dL.
- Subjects who are pregnant, breastfeeding, or unwilling to practice birth control during participation in the study.
- Subjects with chronic constipation.
- Subjects consuming types of food and supplements with the potential to interfere with the study objectives as judged by the Investigator.
Show all 17Show fewer
- Subjects taking any drugs, especially known OATP2B1 substrates (aliskiren, atenolol, celiprolol, fexofenadine, rosuvastatin and ticlopidine, etc.) except birth control hormonal medications.
- 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.
- Subjects with any disease affecting or impairing the function of the liver, kidney, or heart.
- Subjects with gastrointestinal disease, gastrointestinal disorder, or gastrointestinal surgery.
- 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.
- 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.
- 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.
- 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.
- Subjects who have donated whole blood within 8 weeks prior to study initiation or plan to donate blood during the study period.
- Non-English speaking.
- Subjects with abnormal laboratory results at Screening Visit as judged by the Investigator or study physician.
Trial locations and contacts
1 site in 1 country.
About this study
Official title: 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.
Read the 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.
- Being tested
- Fexofenadine Hydrochloride without sodium lauryl sulfate, Fexofenadine Hydrochloride with sodium lauryl sulfate
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Fexofenadine Hydrochloride without sodium lauryl sulfateDrug
Also called Allegra
without sodium lauryl sulfate
Fexofenadine Hydrochloride with sodium lauryl sulfateDrug
Also called Allegra
with sodium lauryl sulfate
| Study group | Role | What they receive |
|---|---|---|
| Fexofenadine without SLS | Experimental | Participants will be administered by mouth with a capsule containing 120 mg fexofenadine hydrochloride and 101 mg microcrystalline cellulose Receives: Drug: Fexofenadine Hydrochloride without sodium lauryl sulfate |
| Fexofenadine and 3 mg SLS | Experimental | Participants will be administered by mouth with a capsule containing 120 mg fexofenadine hydrochloride, 3 mg SLS and 101 mg microcrystalline cellulose Receives: Drug: Fexofenadine Hydrochloride with sodium lauryl sulfate |
| Fexofenadine and 30 mg SLS | Experimental | Participants will be administered by mouth with a capsule containing 120 mg fexofenadine hydrochloride, 30 mg SLS and 101 mg microcrystalline cellulose Receives: Drug: Fexofenadine Hydrochloride with sodium lauryl sulfate |
What is being measured
The primary outcome is the main question the study is designed to answer.
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.
Measured: 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.
Measured: 0-48 hours
Secondary outcomes (3)
Sodium lauryl sulfate plasma concentration
To determine plasma SLS concentration in order to understand the absorption of SLS in humans
Measured: 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.
Measured: 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.
Measured: 0-48 hours
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted1 Sep 2020
- Study start31 Jan 2023
- Primary completion18 Jun 2025
- Study completion18 Aug 2025
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for The Impact of Excipients on Drug AbsorptionStudies of the same condition, open and under way.
- More trials run by University of California, San FranciscoThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Early Phase 1
- Primary purpose
- Basic science
- Allocation
- Randomised
- Intervention model
- Crossover
- Model description
- This is a single-center, randomized, double-blind, 3-period crossover trial. Subjects will be randomized to receive fexofenadine only under Treatment Arm 1 or fexofenadine and 3 mg SLS under Treatment Arm 2 or fexofenadine and 30 mg SLS under Treatment Arm 3.
- Masking
- Double blind
- Who is masked
- Participant, Outcomes assessor
- Enrolment
- 12 participants (actual)
Sponsor and investigators
- Lead sponsor
- University of California, San Francisco
- Sponsor type
- University, hospital or other
- Collaborators
- Food and Drug Administration (FDA)
- Responsible party
- Sponsor
- Investigators
- Katherine Yang, PharmD, MPH, Principal investigator, University of California, San Francisco
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT04534153
- Sponsor's protocol ID
- 20-31871
- Status last verified
- Nov 2025
- First submitted
- 26 Aug 2020
- Last updated
- 18 Nov 2025
- Results posted
- No
- Data monitoring committee
- Yes
- FDA-regulated drug
- Yes
- FDA-regulated device
- No
- Individual data sharing
- Yes: Each participant's data will be de-identified before it is shared with others who meet specified access criteria.
Study at a glance
From the registry record, last updated by the sponsor on 18 Nov 2025. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- The Effect of Sodium Lauryl Sulfate on the Oral Absorption of Fexofenadine in Humans
- ClinicalTrials.gov ID
- NCT04534153
- Acronym / sponsor ID
- 20-31871
- Phase
- Early Phase 1
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 12 participants (actual)
- Lead sponsor
- University of California, San FranciscoUniversity, hospital or other
- Collaborators
- Food and Drug Administration (FDA)
- Study start
- 31 Jan 2023 (actual)
- Primary completion
- 18 Jun 2025 (actual)
- Study completion
- 18 Aug 2025 (actual)
- First posted
- 1 Sep 2020 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
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.
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 design
- Primary purpose
- Basic science
- Allocation
- Randomised
- Intervention model
- Crossover
- Masking
- Double blind (participant, outcomes assessor)
- Number of arms
- 3
- Model description
- This is a single-center, randomized, double-blind, 3-period crossover trial. Subjects will be randomized to receive fexofenadine only under Treatment Arm 1 or fexofenadine and 3 mg SLS under Treatment Arm 2 or fexofenadine and 30 mg SLS under Treatment Arm 3.
| Arm | Type | Receives |
|---|---|---|
| Fexofenadine without SLS | Experimental | Drug: Fexofenadine Hydrochloride without sodium lauryl sulfateParticipants will be administered by mouth with a capsule containing 120 mg fexofenadine hydrochloride and 101 mg microcrystalline cellulose |
| Fexofenadine and 3 mg SLS | Experimental | Drug: Fexofenadine Hydrochloride with sodium lauryl sulfateParticipants will be administered by mouth with a capsule containing 120 mg fexofenadine hydrochloride, 3 mg SLS and 101 mg microcrystalline cellulose |
| Fexofenadine and 30 mg SLS | Experimental | Drug: Fexofenadine Hydrochloride with sodium lauryl sulfateParticipants will be administered by mouth with a capsule containing 120 mg fexofenadine hydrochloride, 30 mg SLS and 101 mg microcrystalline cellulose |
Who may qualify
- Ages
- 18 to 64 years
- Sex
- All
- Healthy volunteers
- Accepted
- Age groups
- Adult
Key inclusion criteria (4 listed)
- Healthy volunteers of all ethnic groups and races.
- Male and females between the ages of 18-64 years old, inclusive.
- 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.
- Written informed consent obtained from the subject and ability for subject to comply with the requirements of the study.
Key exclusion criteria (17 listed)
- Subjects with extreme obesity (BMI > 35).
- Subjects who are allergic to fexofenadine or SLS.
- Subjects who have hemoglobin level lower than 12 g/dL.
- Subjects who are pregnant, breastfeeding, or unwilling to practice birth control during participation in the study.
- Subjects with chronic constipation.
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Fexofenadine Hydrochloride without sodium lauryl sulfateAlso: Allegrawithout sodium lauryl sulfate | Drug | Fexofenadine without SLS |
| Fexofenadine Hydrochloride with sodium lauryl sulfateAlso: Allegrawith sodium lauryl sulfate | Drug | Fexofenadine and 3 mg SLS, Fexofenadine and 30 mg SLS |
Primary outcome
Area under the plasma concentration versus time curve (AUC) of Fexofenadine
Time frame: 0-48 hours
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.
Maximum Plasma Concentration (Cmax) of Fexofenadine
Time frame: 0-48 hours
To determine whether SLS decreases the fexofenadine Cmax between Fexofenadine + 3 mg SLS or Fexofenadine + 30 mg SLS and Fexofenadine only.
3 secondary outcomes
Sodium lauryl sulfate plasma concentration
Time frame: 0-48 hours
Fexofenadine stool amount
Time frame: 0-48 hours
Sodium lauryl sulfate stool amount
Time frame: 0-48 hours
Results and safety
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 18 Nov 2025.
- Individual participant dataSharing planned: Yes. Each participant's data will be de-identified before it is shared with others who meet specified access criteria.
Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
Katherine Yang, PharmD, MPH principal investigator
University of California, San Francisco
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A Early Phase 1 study testing Fexofenadine Hydrochloride without sodium lauryl sulfate and Fexofenadine Hydrochloride with sodium lauryl sulfate in people with The Impact of Excipients on Drug Absorption, run by University of California, San Francisco at 1 site in United States.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 4 inclusion and 17 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: finished, as of the sponsor's last update on 18 Nov 2025. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in United States. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
What does this phase mean?
Early Phase 1 (sometimes called Phase 0) studies give a very small amount of a treatment to a few people, mainly to see how the body handles it.
Not every study follows the same path, and some studies (observational studies, device studies) have no phase.
Are results available for this study?
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Area under the plasma concentration versus time curve (AUC) of Fexofenadine (time frame: 0-48 hours). The study lists 2 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 18 Nov 2025.