Ulipristal Acetate for Emergency Birth Control
What You Need to Know Before You Apply
What is the purpose of this trial?
This trial aims to understand why oral emergency contraception fails for some women but not others. Researchers are testing whether genetic differences, specifically the presence or absence of certain CYP3A5 alleles (gene variations affecting drug metabolism), influence this outcome. Participants will receive a dose of ulipristal acetate, an emergency contraceptive, to observe their body's response. Women who are generally healthy, aged 18-40, and have regular menstrual cycles may be suitable for this study. As a Phase 4 trial, the treatment is already FDA-approved and proven effective, and this research seeks to understand how it benefits more patients.
Will I have to stop taking my current medications?
The trial requires that you stop using drugs that interfere with the study medication within 2 weeks of enrollment. This includes drugs that affect how the body processes the study drug.
What is the safety track record for Ulipristal acetate?
Research has shown that ulipristal acetate is generally safe and well-tolerated as an emergency contraceptive. One study found it safe to take within 48 to 120 hours after unprotected sex. Most people do not experience major side effects. Common but mild side effects include headache, nausea, and stomach pain, while serious side effects are rare.
Since the FDA has approved ulipristal acetate for emergency contraception, it has undergone thorough safety studies. However, limited information exists on its use in people with different medical conditions or genetic backgrounds. This trial aims to explore those genetic differences and their effects, but current evidence supports the safety of ulipristal acetate for general use.12345Why are researchers enthusiastic about this study treatment?
Unlike the standard emergency contraceptive pills that often contain levonorgestrel, Ulipristal acetate works differently by targeting the progesterone receptor to delay or prevent ovulation. This unique mechanism allows Ulipristal acetate to be effective even when taken closer to ovulation, offering a broader window of efficacy compared to other options. Additionally, Ulipristal acetate is a one-time oral dose, making it both convenient and easy to use. Researchers are excited about its potential to provide more reliable emergency contraception, especially for individuals with specific genetic markers like the CYP3A5 allele, which can affect drug metabolism and efficacy.
What is the effectiveness track record for Ulipristal acetate as emergency birth control?
Research shows that ulipristal acetate is a strong option for emergency birth control. In a large study with over 1,500 participants, only 1.9% became pregnant after taking ulipristal acetate, compared to an expected 5.7%. Another study found a pregnancy rate of just 1.2% among women who used it. These findings suggest that ulipristal acetate greatly lowers the chance of pregnancy when used as emergency contraception. It appears to work better than some other options, especially if taken within a few days after unprotected sex. Overall, ulipristal acetate is a dependable choice for preventing pregnancy in emergency situations.
In this trial, participants will receive a single 30mg dose of ulipristal acetate. Researchers will conduct pharmacokinetic and pharmacodynamic testing to assess its effectiveness in individuals with active and inactive CYP3A5 alleles.678910Who Is on the Research Team?
Alison B Edelman, MD, MPH
Principal Investigator
Oregon Health and Science University
Are You a Good Fit for This Trial?
This trial is for generally healthy women aged 18-40 with regular menstrual cycles, who are not pregnant, seeking pregnancy, or breastfeeding. Participants should have no known allergy to the study medication and must not be using certain drugs that affect its metabolism.Inclusion Criteria
Exclusion Criteria
Timeline for a Trial Participant
Screening
Participants are screened for eligibility to participate in the trial
Treatment
Participants receive a single dose of ulipristal acetate 30mg with pharmacokinetic and pharmacodynamics testing
Follow-up
Participants are monitored for follicular rupture and UPA concentration
Follow-up
Participants are monitored for follicular rupture over one menstrual cycle
What Are the Treatments Tested in This Trial?
Interventions
- Ulipristal acetate
Ulipristal acetate is already approved in United States, Canada, European Union for the following indications:
- Emergency contraception
- Emergency contraception
- Uterine fibroids
- Emergency contraception
- Uterine fibroids
Find a Clinic Near You
Who Is Running the Clinical Trial?
Oregon Health and Science University
Lead Sponsor
Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD)
Collaborator