PreeclampsiaPhase 3Optim-PRENCT07665853
Optimizing the Use of Aspirin for the Prevention of Preeclampsia
A Phase 3 study testing Discontinuation of Acetylsalicilic acid 150 mg/day at 24-28 weeks of gestation in people with Preeclampsia, run by Hospital Universitari Vall d'Hebron Research Institute at 38 sites in 7 countries.
Trial summary
Pregnant women at higher risk for preeclampsia (PE) are currently recommended to take low-dose aspirin (acetylsalicylic acid, ASA) daily from the first trimester until 36 weeks of gestation. Read more about this study
- Who is it for?
- Ages 18 years and older, women only
- Conditions the study is for
- Preeclampsia
- What is being tested?
- Discontinuation of Acetylsalicilic acid 150 mg/day at 24-28 weeks of gestation
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 15,160 participants
- Where
- 38 sitesin 7 countries
- Study dates
- 1 Jul 2026to May 2028
- Phase
- Phase 3
- 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 years and older
- Women only
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- Age 18 years or older at time of enrollment.
- Singleton pregnancy.
- Ability to read and understand the informed consent form.
- Having undergone first-trimester preeclampsia screening between 11+0 and 13+6 weeks of gestation using a validated multiparametric algorithm (FMF algorithm at a risk cutoff of 1:100, or Gaussian algorithm at a cutoff of 1:170) and being classified as high risk for preterm preeclampsia.
- Currently taking aspirin 150 mg/day initiated after first-trimester high-risk classification, in accordance with standard clinical practice.
- Voluntary signing of the informed consent form and willingness to comply with the study requirements, including acceptance of the assigned aspirin treatment duration, additional blood tests, and additional ultrasound assessments.
Who cannot join
- Early pregnancy loss, intrauterine fetal death, or fetus with major structural malformations diagnosed at the time of enrollment.
- Fetus affected by a known genetic or chromosomal disease.
- Contraindication, allergy, or intolerance to aspirin (acetylsalicylic acid).
- Any medical condition that makes aspirin discontinuation unsafe or impossible (e.g., antiphospholipid syndrome, mechanical heart valve, or other conditions requiring indefinite antiplatelet or anticoagulant therapy).
Trial locations and contacts
38 sites in 7 countries. Contact the study team or a site near you to ask about taking part.
38 sites in 7 countries
Spain27 sites
Complejo Hospitalario Universitario de A Coruña
A Coruña
Nuria Valiño, 034981178000, Nuria.Valino.Calvino@sergas.es
Hospital General de Alicante
Alicante
Ana Palacios, +34965262297, ana.palacios.marques@gmail.com
Hospital de Cruces
Barakaldo, Vizcaya, 48903
Elena Gibbone, 946 00 60 00, elena.gibbone@osakidetza.eus
Hospital Universitari Dexeus
Barcelona, BARCELONA, 08024
Raquel Mula, +3493 227 47 47, raqmul@dexeus.com
Hospital Universitari Vall d'Hebron
Barcelona, 08035
Manel Mendoza, PhD, 0034934893085 ext. 3264, manel.mendoza@vallhebron.cat
Hospital de la Santa Creu i Sant Pau
Barcelona
Pablo Garcia-Manau, pgarciama@santpau.cat
+34935537048
Hospital Universitari Vall d'Hebrón
Barcelona
Manel Mendoza, +34 93 489 30 00 ext. 6548, manel.mendoza@vallhebron.cat
Mireia Armengol, +34 93 489 30 00 ext. 6548, mireia.armengol@vallhebron.cat
Hospital Universitario de Burgos
Burgos
Leire González, 947281800, lgonzalezm@saludcastillayleon.es
Hospital Universitario Puerta del Mar
Cadiz
Maria Angeles Anaya, +34956 00 21 00, angeles.anaya.sspa@juntadeandalucia.es
Hospital Dr.Josep Trueta
Girona, Girona, 17007
Roser Masó, 972940200 ext. 2235
Hospital San Cecilio
Granada, Andalusia
Elena Benitez, +34958 02 30 00, elena.benitezcano.sspa@juntadeandalucia.es
Hospital Universitario Virgen de las Nieve
Granada
María Setefilla López, +34958 02 00 89, mmefilla@gmail.com
Hospital Universitario de Jerez
Jerez de la Frontera
Cristina Romero, +34956 03 20 00, CRGARRI@GMAIL.COM
Hospital Materno Infantil de Gran Canaria
Las Palmas de Gran Canaria
Laura Molero, +34 928 444 830, lmolsal@gobiernodecanarias.org
Hospital Universitario Severo Ochoa
Leganés
Laura De Mingo, +34 914818000, laura.demingo@salud.madrid.org
Hospital de León
León
Camino Fernandez, 34-987 237 400, cfdezfdez@saludcastillayleon.es
Hospital Arnau de Vilanova de Lleida
Lleida
Ivanna Llordella, Lsarmiento.lleida.ics@gencat.cat
Fundación Jiménez Díaz
Madrid
Miguel Alvaro Navidad, (+34)915 50 48 00, MAlvaro@quironsalud.es
Hospital Universitario Rey Juan Carlos
Móstoles
Marina Perez Serrano, +34 914816225, marina.pserrano@hospitalreyjuancarlos.es
Hospital Clínico Universitario Virgen de la Arrixaca
Murcia
Laura Hernandez, +34968 36 95 00, sms_medicinafetalmurcia@carm.es
Clínica Universidad de Navarra
Pamplona
Laura Muñoz Saa, lmunozs@unav.es
Hospital Universitario de Canarias
San Cristóbal de La Laguna
Mercedes Hernández, +34922 67 80 00, mercedes021281@hotmail.com
Armando Torres, MD, PhD, +34 922 31 93 38, atorres@gmail.com
Hospital Universitario Nuestra Señora de Candelaria
Santa Cruz de Tenerife
Sara Caamiña, sara_caaminya@hotmail.com
Hospital Joan XXIII
Tarragona, Tarragona, 43007
Monica Lopez, +34977295800, mlopezrodriguez.hj23.ics@gencat.cat
Consorci Sanitari de Terrassa
Terrassa
Angels Vives, MAVives@cst.cat
Hospital Universitari Mútua Terrassa
Terrassa
Eva Lopez-Quesada, (+34) 937365050 ext. 20361, evalopez@mutuaterrassa.es
Hospital Universitario de Torrejón
Torrejón de Ardoz
Raquel Martin, MD, +34916262626, raqmaral@gmail.com
Austria2 sites
Medical University of Vienna
Vienna
Gülen Yerlikaya-Schatten, +43 1 401600, guelen.yerlikaya@meduniwien.ac.at
St Josef Hospital
Vienna
Sarah, s.lausegger@gmx.at
Ghana2 sites
Saint Patrick Hospital
Ofinso
Seth Ampor, +233 5427 21341, sethonto@gmail.com
Holy Family Hospital
Techiman
Seryam Kaali, +233 546381925, kaali.seyram@kintampo-hrc.org
Senegal2 sites
Hopital Phillipe Senghor
Dakar
Mamour Gueye, +221 33 820 12 28, mamourmb@gmail.com
Centre Hospitalier Régional de Saint-Louis
Saint-Louis
Thian Ousman, +221772890244, cassoumane@yahoo.fr
The Gambia2 sites
Bundung Maternal and Child Health Hospital
Banjul
Dado Jarju, +220 7933758, jabbiedado29@gmail.com
Brikama District Hospital
Brikama
Karamba Suwareh, +2203379857, k.suwareh@yahoo.com
United Kingdom2 sites
King's College Hospital
London
Argyro Syngelaki, +44 20 7836 5454, argyro.syngelaki@nhs.net
Medway Maritime Hospital
London
Ranjit Akolekar, +44 1634 830000, ranjit.akolekar@gmail.com
Bulgaria1 site
Dr Shterev Hospital
Sofia
Petya Chaveeva, +359 2 920 0901, international@shterevhospital.com
About this study
Pregnant women at higher risk for preeclampsia (PE) are currently recommended to take low-dose aspirin (acetylsalicylic acid, ASA) daily from the first trimester until 36 weeks of gestation. High-risk women are identified through a multiparametric first-trimester screening that combines maternal history, blood pressure, uterine artery blood flow, and placental growth factor (PlGF). Although this screening effectively identifies women at risk, the majority of those classified as high risk will not develop PE. As a result, a large proportion of pregnant women receive prolonged aspirin treatment without benefit, while remaining exposed to its potential side effects, including increased bleeding risk.
Aspirin prevents PE primarily by improving placental development during the first half of pregnancy. Whether continuing ASA beyond 24-28 weeks provides additional protection remains unclear. A previous randomized trial demonstrated that stopping ASA at 24-28 weeks was non-inferior to continuing until 36 weeks in a predominantly European population. However, whether this finding applies to more diverse populations, including women of African origin who carry a substantially higher baseline risk of PE, has not been established.
This is a multicenter, randomized, open-label, parallel-group, phase III non-inferiority trial conducted across sites in Europe and Africa. A total of 15,160 pregnant women at high risk for PE from first-trimester screening, currently under ASA treatment, will be randomized in a 1:1 ratio before 28 weeks of gestation to either discontinue ASA at 24-28 weeks or continue ASA until 36 weeks of gestation.
Read the detailed description
The primary objective of the study is to demonstrate that in pregnant women at high risk for preeclampsia from first-trimester multiparametric screening, the incidence of preterm PE after discontinuation of ASA at 24-28 weeks of gestation is non-inferior to that of the control group, who continue ASA until 36 weeks.
- Conditions
- Preeclampsia
- Being tested
- Discontinuation of Acetylsalicilic acid 150 mg/day at 24-28 weeks of gestation
- Keywords
- Preeclampsia, First Trimester Screening, Placental Growth Factor, Ophthalmic Artery Doppler, Acetyl Salicylic Acid (ASA)
- Medical subject headings
- Pre-Eclampsia
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Discontinuation of Acetylsalicilic acid 150 mg/day at 24-28 weeks of gestationDrug
Intervention group will discontinuate of Acetyl Salicylic acid at 24-28 weeks of gestation while Control Group will continue Acetyl Salicylic acid 150 mg/day until 36 weeks of gestation.
| Study group | Role | What they receive |
|---|---|---|
| ASA withdrawn group | Experimental | ASA is discontinued at 24-28 weeks of gestation Receives: Drug: Discontinuation of Acetylsalicilic acid 150 mg/day at 24-28 weeks of gestation |
| Continue ASA Group | No intervention | ASA is continued until 36 weeks of gestation |
What is being measured
The primary outcome is the main question the study is designed to answer.
Rate of preterm preeclampsia in both arms of the study (ASA vs no ASA).
Rate of pre-eclampsia <37 weeks in pregnant women at high-risk for early-onset PE from the first-trimester screening in both arms of the study (ASA vs no ASA).
Measured: From 20 weeks of gestation onwards
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted24 Jun 2026
- Study start1 Jul 2026 (estimated)
- Primary completionMay 2028 (estimated)
- Study completionMay 2028 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for PreeclampsiaStudies of the same condition, open and under way.
- More trials run by Hospital Universitari Vall d'Hebron Research InstituteThe 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 3
- Primary purpose
- Prevention
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- None (open label)
- Enrolment
- 15,160 participants (estimated)
Sponsor and investigators
- Sponsor type
- University, hospital or other
- Collaborators
- Fetal Medicine Foundation
- Responsible party
- Sponsor
- Investigators
- Manel Mendoza Cobaleda, Professor, Principal investigator, Hospital Universitari Vall Hebron - Vall Hebrón Institut de RecercaKypros Nicolaides, Professor, Principal investigator, Fetal Medicine Foundation
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07665853
- Sponsor's protocol ID
- Optim-PRE26
- Other IDs
- INV-093057, INV-108812, PI25/00497, 2025-524646-94-00, 2025
- Acronym
- Optim-PRE
- Status last verified
- Jun 2026
- First submitted
- 18 Jun 2026
- Last updated
- 24 Jun 2026
- Results posted
- No
- Data monitoring committee
- Yes
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- Yes: Upon publication, anonymized data will be deposited in the VHIR's institutional open research data repository.
Study at a glance
From the registry record, last updated by the sponsor on 24 Jun 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Optimizing the Use of Aspirin for the Prevention of Preeclampsia
- ClinicalTrials.gov ID
- NCT07665853
- Acronym / sponsor ID
- Optim-PRE / Optim-PRE26
- Conditions
- Preeclampsia
- Keywords
- Preeclampsia, First Trimester Screening, Placental Growth Factor, Ophthalmic Artery Doppler, Acetyl Salicylic Acid (ASA)
- Phase
- Phase 3
- Study type
- Interventional
- Recruitment status
- Not yet recruiting
- Enrolment
- 15,160 participants (estimated)
- Lead sponsor
- Hospital Universitari Vall d'Hebron Research InstituteUniversity, hospital or other
- Collaborators
- Fetal Medicine Foundation
- Study start
- 1 Jul 2026 (estimated)
- Primary completion
- May 2028 (estimated)
- Study completion
- May 2028 (estimated)
- First posted
- 24 Jun 2026 (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.
Pregnant women at higher risk for preeclampsia (PE) are currently recommended to take low-dose aspirin (acetylsalicylic acid, ASA) daily from the first trimester until 36 weeks of gestation. High-risk women are identified through a multiparametric first-trimester screening that combines maternal history, blood pressure, uterine artery blood flow, and placental growth factor (PlGF). Although this screening effectively identifies women at risk, the majority of those classified as high risk will not develop PE. As a result, a large proportion of pregnant women receive prolonged aspirin treatment without benefit, while remaining exposed to its potential side effects, including increased bleeding risk.
Aspirin prevents PE primarily by improving placental development during the first half of pregnancy. Whether continuing ASA beyond 24-28 weeks provides additional protection remains unclear. A previous randomized trial demonstrated that stopping ASA at 24-28 weeks was non-inferior to continuing until 36 weeks in a predominantly European population. However, whether this finding applies to more diverse populations, including women of African origin who carry a substantially higher baseline risk of PE, has not been established.
This is a multicenter, randomized, open-label, parallel-group, phase III non-inferiority trial conducted across sites in Europe and Africa. A total of 15,160 pregnant women at high risk for PE from first-trimester screening, currently under ASA treatment, will be randomized in a 1:1 ratio before 28 weeks of gestation to either discontinue ASA at 24-28 weeks or continue ASA until 36 weeks of gestation.
Detailed description
The primary objective of the study is to demonstrate that in pregnant women at high risk for preeclampsia from first-trimester multiparametric screening, the incidence of preterm PE after discontinuation of ASA at 24-28 weeks of gestation is non-inferior to that of the control group, who continue ASA until 36 weeks.
Study design
- Primary purpose
- Prevention
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- None (open label)
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| ASA withdrawn group | Experimental | Drug: Discontinuation of Acetylsalicilic acid 150 mg/day at 24-28 weeks of gestationASA is discontinued at 24-28 weeks of gestation |
| Continue ASA Group | No intervention | –ASA is continued until 36 weeks of gestation |
Who may qualify
- Ages
- 18 years and older
- Sex
- Female only
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (6 listed)
- Age 18 years or older at time of enrollment.
- Singleton pregnancy.
- Ability to read and understand the informed consent form.
- Having undergone first-trimester preeclampsia screening between 11+0 and 13+6 weeks of gestation using a validated multiparametric algorithm (FMF algorithm at a risk cutoff of 1:100, or Gaussian algorithm at a cutoff of 1:170) and being classified as high risk for preterm preeclampsia.
- Currently taking aspirin 150 mg/day initiated after first-trimester high-risk classification, in accordance with standard clinical practice.
Key exclusion criteria (4 listed)
- Early pregnancy loss, intrauterine fetal death, or fetus with major structural malformations diagnosed at the time of enrollment.
- Fetus affected by a known genetic or chromosomal disease.
- Contraindication, allergy, or intolerance to aspirin (acetylsalicylic acid).
- Any medical condition that makes aspirin discontinuation unsafe or impossible (e.g., antiphospholipid syndrome, mechanical heart valve, or other conditions requiring indefinite antiplatelet or anticoagulant therapy).
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 |
|---|---|---|
| Discontinuation of Acetylsalicilic acid 150 mg/day at 24-28 weeks of gestationIntervention group will discontinuate of Acetyl Salicylic acid at 24-28 weeks of gestation while Control Group will continue Acetyl Salicylic acid 150 mg/day until 36 weeks of gestation. | Drug | ASA withdrawn group |
Primary outcome
Rate of preterm preeclampsia in both arms of the study (ASA vs no ASA).
Time frame: From 20 weeks of gestation onwards
Rate of pre-eclampsia <37 weeks in pregnant women at high-risk for early-onset PE from the first-trimester screening in both arms of the study (ASA vs no ASA).
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 24 Jun 2026.
- Individual participant dataSharing planned: Yes. Upon publication, anonymized data will be deposited in the VHIR's institutional open research data repository.
Related trials for Preeclampsia
Recruiting
Exercise to Improve Heart and Metabolic Health After Childbirth in Women at High Risk for Preeclampsia
Postpartum Exercise, Cardiometabolic Health
RecruitingObservational study
Molecular Study of the Maternal-fetal Interface in Preeclampsia.
Preeclampsia
Active, not recruitingObservational study
The CoPenHagen PREeClampsia and cardIOvascUlar diSease Study
Pre-Eclampsia, Atherosclerosis
RecruitingObservational study
Estimated Risk of Preeclampsia in the First Trimester and Its Association With Subclinical Atherosclerosis and Cardiovascular Risk in Women With Type 1 Diabetes
Type 1 Diabetes, Preeclampsia
Not yet recruitingPhase 2
Furosemide vs Placebo in Severe Preeclampsia Postpartum
Severe Preeclampsia
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.
Manel Mendoza Cobaleda, Professor principal investigator
Hospital Universitari Vall Hebron - Vall Hebrón Institut de Recerca
Kypros Nicolaides, Professor principal investigator
Fetal Medicine Foundation
38 sites in 7 countries: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A Phase 3 study testing Discontinuation of Acetylsalicilic acid 150 mg/day at 24-28 weeks of gestation in people with Preeclampsia, run by Hospital Universitari Vall d'Hebron Research Institute at 38 sites in 7 countries.
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 6 inclusion and 4 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: opening soon, as of the sponsor's last update on 24 Jun 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 38 sites in Spain, Austria, Ghana, Senegal, The Gambia and 2 more countries. 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 3 studies compare the treatment with the current standard treatment or a placebo in a large group, to confirm how well it works and watch for side effects.
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 Manel Mendoza Cobaleda, Professor (+34 93 489 30 00 ext. 6548, manel.mendoza@vallhebron.cat), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Rate of preterm preeclampsia in both arms of the study (ASA vs no ASA). (time frame: From 20 weeks of gestation onwards). 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 24 Jun 2026.