Contraceptive UsagePhase 4NCT05674513
Disparities in Emergency Contraceptive Metabolism Dictate Efficacy
A Phase 4 study testing Ulipristal acetate in people with Contraceptive Usage, run by Oregon Health and Science University at 1 site in United States.
Trial summary
The purpose of this study is to learn more about why some people are at greater risk for oral emergency contraceptive failure while others are not. The investigators want to learn if genetic differences impact the risk of emergency contraception failure. Read more about this study
- Who is it for?
- Ages 18 to 40 years, women onlyHealthy volunteers can take part
- Conditions the study is for
- Contraceptive Usage
- What is being tested?
- Ulipristal acetate
- Type of treatment
- Pill or oral medicine
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 140 participants
- Where
- 1 siteUnited States
- Study dates
- 9 Jan 2023to 31 Dec 2027
- Phase
- Phase 4
- Are there results?
- Not yet: the study is under way
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 40 years
- Women only
- Healthy volunteers accepted
- Adult
Who may be able to join
- Generally healthy women
- Aged 18-40
- regular menses (every 21-35 days) experiencing ovulatory cycles proven by a single progesterone level of 3 ng/mL or greater during the luteal phase of the screening cycle.
Who cannot join
- Pregnant, seeking pregnancy, or breastfeeding
- Known allergy to study medication
- Recent use of hormonal contraception
- Irregular periods (<21 days or >35 day cycles)
- Routine use of nonsteroidal anti-inflammatory drugs
- Metabolic disorders
Show all 9Show fewer
- Smoking
- Any condition that would preclude the provision of informed consent
- Using drugs (within 2 weeks of study enrollment) known to interfere with the metabolism of UPA as well as drugs known to be CYP3A4 inducers, inhibitors, or CYP3A drug substrates
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
United States1 site, 1 recruiting
- Recruiting
OHSU
Portland, Oregon, 97239
About this study
The purpose of this study is to learn more about why some people are at greater risk for oral emergency contraceptive failure while others are not. The investigators want to learn if genetic differences impact the risk of emergency contraception failure.
Read the detailed description
Each of us can respond differently to a drug or medication based on our genetics. An emergency contraceptive, ulipristal acetate or UPA, normally works by stopping or delaying the ovary from releasing an egg (ovulation). Our bodies break down UPA in order to use it through a system call the cytochrome P450 pathway but this pathway can be faster or slower depending on our genetics. The investigators want to learn more about how our individual genetic differences in this pathway change how the ovary responds to UPA. The overall goal of this research is to improve the effectiveness of emergency contraception for all people.
- Conditions
- Contraceptive Usage
- Being tested
- Ulipristal acetate
- Keywords
- Ulipristal acetate, Emergency contraception
- Medical subject headings
- Contraception Behavior
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Ulipristal acetateDrug
Evaluating the pharmacodynamic and pharmacokinetic outcomes after 1 dose of Ulipristal acetate 30mg in individuals with and without active CYP3A5 alleles
| Study group | Role | What they receive |
|---|---|---|
| Active CYP3A5 Allele | Active comparator | Ulipristal acetate 30mg orally x 1 dose with pharmacokinetic and pharmacodynamics testing in individuals with active CYP3A5 alleles Receives: Drug: Ulipristal acetate |
| Inactive CYP3A5 Allele | Active comparator | Ulipristal acetate 30mg orally x 1 dose with pharmacokinetic and pharmacodynamics testing in individuals without active CYP3A5 alleles Receives: Drug: Ulipristal acetate |
What is being measured
The primary outcome is the main question the study is designed to answer.
Delay in follicular rupture
Follicular rupture (yes/no) by ultrasound. Defined as the disappearance of or >50% reduction in size of the leading follicle
Measured: over 1 menstrual cycle (assessed up to approximately 30 days)
Concentration of UPA
mean concentration maximum (Cmax) for UPA
Measured: 5 days after taking study drug
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted6 Jan 2023
- Study start9 Jan 2023
- Primary completion31 Dec 2026 (estimated)
- Study completion31 Dec 2027 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Contraceptive UsageStudies of the same condition, open and under way.
- More trials run by Oregon Health and Science UniversityThe 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
- Phase 4
- Primary purpose
- Treatment
- Allocation
- Non-randomised
- Intervention model
- Single group
- Masking
- None (open label)
- Enrolment
- 140 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Oregon Health and Science University
- Sponsor type
- University, hospital or other
- Collaborators
- Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD)
- Responsible party
- Principal investigator, Alison Edelman, Oregon Health and Science University
- Investigators
- ALISON EDELMAN, MD, Principal investigator, Oregon Health and Science University
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT05674513
- Sponsor's protocol ID
- STUDY00024952
- Other IDs
- 1R01HD105866-01A1
- Status last verified
- Jul 2026
- First submitted
- 15 Dec 2022
- Last updated
- 9 Jul 2026
- Results posted
- No
- FDA-regulated drug
- Yes
- FDA-regulated device
- No
Study at a glance
From the registry record, last updated by the sponsor on 9 Jul 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Disparities in Emergency Contraceptive Metabolism Dictate Efficacy
- ClinicalTrials.gov ID
- NCT05674513
- Acronym / sponsor ID
- STUDY00024952
- Conditions
- Contraceptive Usage
- Keywords
- Ulipristal acetate, Emergency contraception
- Phase
- Phase 4
- Study type
- Interventional
- Recruitment status
- Recruiting
- Enrolment
- 140 participants (estimated)
- Lead sponsor
- Oregon Health and Science UniversityUniversity, hospital or other
- Collaborators
- Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD)
- Study start
- 9 Jan 2023 (actual)
- Primary completion
- 31 Dec 2026 (estimated)
- Study completion
- 31 Dec 2027 (estimated)
- First posted
- 6 Jan 2023 (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 learn more about why some people are at greater risk for oral emergency contraceptive failure while others are not. The investigators want to learn if genetic differences impact the risk of emergency contraception failure.
Detailed description
Each of us can respond differently to a drug or medication based on our genetics. An emergency contraceptive, ulipristal acetate or UPA, normally works by stopping or delaying the ovary from releasing an egg (ovulation). Our bodies break down UPA in order to use it through a system call the cytochrome P450 pathway but this pathway can be faster or slower depending on our genetics. The investigators want to learn more about how our individual genetic differences in this pathway change how the ovary responds to UPA. The overall goal of this research is to improve the effectiveness of emergency contraception for all people.
Study design
- Primary purpose
- Treatment
- Allocation
- Non-randomised
- Intervention model
- Single group
- Masking
- None (open label)
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| Active CYP3A5 Allele | Active comparator | Drug: Ulipristal acetateUlipristal acetate 30mg orally x 1 dose with pharmacokinetic and pharmacodynamics testing in individuals with active CYP3A5 alleles |
| Inactive CYP3A5 Allele | Active comparator | Drug: Ulipristal acetateUlipristal acetate 30mg orally x 1 dose with pharmacokinetic and pharmacodynamics testing in individuals without active CYP3A5 alleles |
Who may qualify
- Ages
- 18 to 40 years
- Sex
- Female only
- Healthy volunteers
- Accepted
- Age groups
- Adult
Key inclusion criteria (3 listed)
- Generally healthy women
- Aged 18-40
- regular menses (every 21-35 days) experiencing ovulatory cycles proven by a single progesterone level of 3 ng/mL or greater during the luteal phase of the screening cycle.
Key exclusion criteria (9 listed)
- Pregnant, seeking pregnancy, or breastfeeding
- Known allergy to study medication
- Recent use of hormonal contraception
- Irregular periods (<21 days or >35 day cycles)
- Routine use of nonsteroidal anti-inflammatory drugs
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 |
|---|---|---|
| Ulipristal acetateEvaluating the pharmacodynamic and pharmacokinetic outcomes after 1 dose of Ulipristal acetate 30mg in individuals with and without active CYP3A5 alleles | Drug | Active CYP3A5 Allele, Inactive CYP3A5 Allele |
Primary outcome
Delay in follicular rupture
Time frame: over 1 menstrual cycle (assessed up to approximately 30 days)
Follicular rupture (yes/no) by ultrasound. Defined as the disappearance of or >50% reduction in size of the leading follicle
Concentration of UPA
Time frame: 5 days after taking study drug
mean concentration maximum (Cmax) for UPA
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 9 Jul 2026.
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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.
ALISON EDELMAN, MD principal investigator
Oregon Health and Science University
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A Phase 4 study testing Ulipristal acetate in people with Contraceptive Usage, run by Oregon Health and Science University 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 3 inclusion and 9 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: looking for participants now, as of the sponsor's last update on 9 Jul 2026. 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?
Phase 4 studies take place after a treatment is approved, to learn more about its long-term benefits and risks in everyday use.
Not every study follows the same path, and some studies (observational studies, device studies) have no phase.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Women's Health Research Unit Department of OB/GYN (503-494-3666, whru@ohsu.edu), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Delay in follicular rupture (time frame: over 1 menstrual cycle (assessed up to approximately 30 days)). 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 9 Jul 2026.