Evaluating the use of ulipristal acetate with and without misoprostol for contragestion
| ISRCTN | ISRCTN78613350 |
|---|---|
| DOI | https://doi.org/10.1186/ISRCTN78613350 |
| Secondary identifying numbers | 1001 |
- Submission date
- 28/09/2025
- Registration date
- 15/10/2025
- Last edited
- 15/10/2025
- Recruitment status
- Not yet recruiting
- Overall study status
- Ongoing
- Condition category
- Pregnancy and Childbirth
Plain English summary of protocol
Background and study aims
This proof-of-concept study will assess the safety, efficacy, and acceptability of use of ulipristal acetate (UPA) with and without misoprostol for prevention and/or disruption of early pregnancy processes through 35 days since the last menstrual period (LMP). Although UPA is known to be effective when used before ovulation for pregnancy prevention, and recent evidence suggests it is highly effective when used with misoprostol for termination of confirmed pregnancies up to 63 days LMP, its potential for pregnancy prevention and/or disruption in the initial post-ovulatory period through 35 days LMP has not been studied in humans. If either regimen is shown is found to be safe, effective and acceptable when used as a contragestive through 35 days LMP, this would fill an important gap in available fertility control methods.
Who can participate?
Women at risk of unwanted pregnancy who are between the ages of 18 and 39 years, over 5 days since unprotected intercourse and 35 days or less since the last menstrual period (LMP)
What does the study involve?
Participants will provide a blood sample at the time of enrollment and will then be randomly assigned to receive either 60 mg of ulipristal acetate followed by 800 mcg misoprostol 24 hours later, or 60 mg of ulipristal acetate followed by placebo pills 24 hours later. Follow-up takes place at the study clinic approximately 14 days after taking the ulipristal acetate and includes a pregnancy test and exit interview and, for those with a positive test result, an ultrasound. The main outcomes assessed are pregnancy status at follow-up, safety and patient satisfaction.
What are the possible benefits and risks of participating?
Participants may benefit from access to a safe and effective option for pregnancy prevention and/or disruption under close medical supervision. Risks include expected side effects of the medications, including cramps, bleeding, nausea, vomiting, chills and fever. Serious side effects are rare but monitored closely, and clinical care is provided if needed.
Where is the study run from?
The study is carried out in one maternity hospital in Mexico City (Hospital Materno Infantil Inguarán) and three private clinics in Mexico City (Cuidado Integral de la Mujer, Gineclinic, S.C., Integra, MDK, and Centro Médico Mujer).
What is the study starting date and how long is it expected to run for?
October 2024 to December 2026
Who is funding the study?
The study is jointly funded by Verge Research (New York, USA) and the Secretaría de Salud de la Ciudad de México (SEDESA)
Who is the main contact?
Manuel Bousiéguez, (Senior Associate, Verge Research), mbousieguez@vergeresearch.org
Contact information
Public, Scientific, Principal investigator
41 Purdy Avenue #663
Rye
10580
United States of America
| Phone | +1 (0)9172879052 |
|---|---|
| wsheldon@vergeresearch.org |
Principal investigator
Parque Bosencheve numero 2, interior 8, Colonia El Parque
Naulcalpan
53398
Mexico
| Phone | +52 (0)55 2300 1401 |
|---|---|
| martinezangelica995@gmail.com |
Principal investigator
Agricultura # 45 PH 4. Col. Escandon
Mexico City
11800
Mexico
| Phone | +52 (0)55 5418-6607 |
|---|---|
| mbousieguez@vergeresearch.org |
Study information
| Study design | Multicenter interventional doubled-blinded randomized controlled trial |
|---|---|
| Primary study design | Interventional |
| Secondary study design | Randomised controlled trial |
| Study setting(s) | Hospital, Other |
| Study type | Prevention, Treatment, Safety, Efficacy |
| Participant information sheet | Not available in web format, please use the contact details to request a participant information sheet |
| Scientific title | Safety, efficacy and acceptability of ulipristal acetate with and without misoprostol for contragestion through 35 days LMP |
| Study objectives | To evaluate the safety, efficacy, and acceptability of using 60 mg of ulipristal acetate, alone or in combination with 800 mcg of misoprostol, for preventing and/or terminating unwanted pregnancy up to 35 days since a woman's last menstrual period (LMP). |
| Ethics approval(s) |
1. Approved 05/05/2025, Allendale Investigational Review Board (30 Neck Road, Old Lyme, CT, 06371, United States of America; +1 (0)860 575 0092; erin.staab@allendaleirb.com), ref: Protocol #1001 2. Submitted 19/08/2025, Research Ethics Committee, Belisario Domínguez Specialty Hospital (Av. Tláhuac No. 4866, esq. Zacatlán. Col. San Lorenzo Texcoco. Alcaldía Iztapalapa, Mexico City, 09790, Mexico; +1 (0)52 55 5850 0000 Ext. 1064; dgpcs.correspondencia@salud.cdmx.gob.mx), ref: N/A (number will be provided after approval) |
| Health condition(s) or problem(s) studied | Prevention or disruption of unwanted pregnancy in women up to 35 days LMP |
| Intervention | Arm 1: 60 mg (two 30 mg tablets) ulipristal acetate orally, followed 24 hours later by 800 mcg (four 200 mcg tablets) of misoprostol buccally. Arm 2: 60 mg (two 30 mg tablets) ulipristal acetate orally, followed 24 hours later by four placebo tablets buccally. Randomization is 1:1 and carried out in blocks of 8 for each study site using a computer program. |
| Intervention type | Drug |
| Pharmaceutical study type(s) | Dose response |
| Phase | Phase I/II |
| Drug / device / biological / vaccine name(s) | Ulipristal acetate, misoprostol |
| Primary outcome measure | Proportion of study participants not pregnant at follow-up, as determined by urine pregnancy test and, for those with a positive urine test, ultrasound |
| Secondary outcome measures | 1. Self-reported incidence of side effects (diarrhea, nausea/vomiting, cramps, fever, chills or other) after taking the study medications, as measured by an exit interview at follow-up. 2. Acceptability of the contragestive medications to participants, defined as the proportion of participants who report at follow-up that the medications were acceptable or highly acceptable. 3. Incidence of bleeding within five days after administering the study medications, defined as the proportion of participants who report at follow-up that they experienced any bleeding in the first 5 days after taking the study medications. 4. Duration of bleeding in days following administration of the study medications, defined as the number of days that participants report experiencing bleeding after taking the study medications, as measured by an exit interview at follow-up. 5. Severity of bleeding following administration of study medications, defined as the proportion of participants who report that the bleeding they experienced was very severe, somewhat severe, or not severe at all, as measured by an exit interview at follow-up. |
| Overall study start date | 01/10/2024 |
| Completion date | 31/12/2026 |
Eligibility
| Participant type(s) | Healthy volunteer |
|---|---|
| Age group | Other |
| Lower age limit | 18 Years |
| Upper age limit | 39 Years |
| Sex | Female |
| Target number of participants | 500 |
| Key inclusion criteria | 1. Age 18-39 years 2. LMP ≤35 days, as verified by report of last menstrual period 3. Missed the EC window (had unprotected sex >5 days ago) 4. General good health 5. Does not want to be pregnant 6. History of regular monthly menstrual cycles (±3 days) 7. Willing and able to understand and sign consent forms 8. Willing to return for a follow-up visit 9. Willing to provide a blood draw at enrollment and urine sample at follow-up |
| Key exclusion criteria | 1. Known allergies or contraindications to either of the study drugs 2. Symptoms of or risk factors for ectopic pregnancy, including: 2.1. Unilateral pelvic pain or significant bilateral pelvic pain within the past week 2.2. Prior ectopic pregnancy 2.3. Prior permanent contraception or other tubal surgery 3. Current use of an IUD, contraceptive implant or injectable 4. History of renal or liver disease |
| Date of first enrolment | 01/11/2025 |
| Date of final enrolment | 31/12/2026 |
Locations
Countries of recruitment
- Mexico
Study participating centres
Col. Felipe Ángeles
Alc. Venustiano Carranza
Mexico City
15310
Mexico
Los Alpes
Álvaro Obregón
Mexico City
01010
Mexico
Roma Sur
Cuauhtémoc
Mexico City
06760
Mexico
Polanco Iv Sección
Miguel Hidalgo
Mexico City
11560
Mexico
Sponsor information
Research organisation
41 Purdy Avenue #663
Rye
10580
United States of America
| Phone | +1 (0)917 287 9052 |
|---|---|
| wsheldon@vergeresearch.org | |
| Website | https://vergeresearch.org |
Funders
Funder type
Charity
Private sector organisation / Trusts, charities, foundations (both public and private)
- Alternative name(s)
- David & Lucile Packard Foundation, The David and Lucile Packard Foundation, Packard Foundation, The Packard Foundation, The David & Lucile Packard Foundation, Packard, DLPF, PF
- Location
- United States of America
No information available
No information available
Results and Publications
| Intention to publish date | 01/03/2027 |
|---|---|
| Individual participant data (IPD) Intention to share | No |
| IPD sharing plan summary | Data sharing statement to be made available at a later date |
| Publication and dissemination plan | Results will be shared with the research team and health authorities of the Secretaría de Salud de la Ciudad de México (SEDESA). Findings will also be presented to relevant stakeholders. Results are expected to be disseminated through presentations at professional meetings and publication in a peer-reviewed scientific journal. |
| IPD sharing plan | The data sharing plans for the current study are unknown and will be made available at a later date. |
Editorial Notes
29/09/2025: Study's existence confirmed by the Allendale Investigational Review Board.
