Daily versus split-dose aspirin in high-risk pregnancies
Dose Based Aspirin Pharmacokinetics and Pharmacodynamics in Pregnancy and Association With Pregnancy Outcomes
This test compares taking aspirin 162 mg once daily versus 81 mg twice daily to see which dosing better prevents preeclampsia and preterm birth in people with high-risk singleton pregnancies who start aspirin before 16 weeks.
Quick facts
| Phase | Phase1; Phase2 |
|---|---|
| Study type | Interventional |
| Enrollment | 400 (estimated) |
| Ages | 16 Years to 55 Years |
| Sex | Female |
| Sponsor | Thomas Jefferson University Academic / other |
| Locations | 1 site (Philadelphia, Pennsylvania) |
| Trial ID | NCT06826859 on ClinicalTrials.gov |
What this trial studies
This unblinded, randomized Phase I/II trial enrolls people with a singleton pregnancy before 16 weeks who are recommended aspirin for preeclampsia prevention and randomizes them to 162 mg once daily or 81 mg twice daily. The primary outcome is platelet inhibition measured by PFA-100 epinephrine closure time at 2–4 weeks after initiation and again at 28–32 weeks, and a subset will join a pharmacokinetic sub-study to measure aspirin levels at the two dosing schedules. Secondary outcomes include urine thromboxane, platelet-associated microRNAs, and analysis of how individual factors affect aspirin pharmacokinetics and pharmacodynamics in pregnancy. Investigators will relate these pharmacologic markers to clinical pregnancy outcomes including preeclampsia and preterm birth.
Who should consider this trial
Good fit: Ideal candidates are people aged 16–55 with a singleton gestation under 16 weeks who meet USPSTF criteria for high preeclampsia risk and have been recommended to take 162 mg aspirin.
Not a fit: Patients with aspirin contraindications, current or planned anticoagulation, known bleeding or platelet disorders, multiple gestation, or abnormal baseline platelet function are unlikely to be eligible or to receive benefit from this dosing comparison.
Why it matters
Potential benefit: If successful, this could identify an inexpensive, practical aspirin dosing approach that reduces preeclampsia and preterm birth in high-risk pregnancies.
How similar studies have performed: Low-dose aspirin has been shown to reduce preeclampsia risk in high-risk pregnancies, but split-dose regimens and detailed pregnancy-specific pharmacokinetic data are novel and have limited prior evidence.
Eligibility criteria
Show full inclusion / exclusion criteria
Inclusion Criteria * Singleton gestation gestational age \<16 0/7 weeks, dating confirmed with ultrasound * ≥1 high risk factor for preeclampsia or ≥2 moderate risk factors as per United States Preventative Services Task Force (2021) * Recommendation for 162mg aspirin daily in pregnancy * Age 16-55 years old Exclusion criteria * Contraindication to aspirin * Current or planned use of any other anticoagulation * Thrombocytopenia, other known platelet or bleeding disorder * Abnormally elevated baseline PFA-100 epinephrine closure time prior to aspirin initiation
Where this trial is running
Philadelphia, Pennsylvania
- Thomas Jefferson University — Philadelphia, Pennsylvania, United States (Recruiting)
Study contacts
- Study coordinator: Rupsa C Boelig, MD
- Email: rupsa.boelig@jefferson.edu
- Phone: 215-955-5000
How to participate
- Review the eligibility criteria above with your treating physician.
- Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
- Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.