Antenatal Platelet Response on Aspirin: a Pharmacokinetic Study Through Pregnancy


Longitudinal pharmacokinetic and pharmacodynamic study in first and third trimester of pregnancy

Full Title of Study: “Impact of Maternal Aspirin Tehrapy on the Maternal/Fetal Unit at Delivery: a Study of Aspirin Pharmacokinetics, Pharmacodynamics, and Pharmacogenomics Through Pregnancy”

Study Type

  • Study Type: Interventional
  • Study Design
    • Allocation: N/A
    • Intervention Model: Single Group Assignment
    • Primary Purpose: Other
    • Masking: None (Open Label)
  • Study Primary Completion Date: June 22, 2022

Detailed Description

This will be a longitudinal addition to an existing R21cohort enrolled in the first trimester to include a first and third trimester assessment of pharmacokinetics/pharmacodynamics (PK/PD) of aspirin and how individual factors impact aspirin PK/PD in pregnancy.


  • Drug: Aspirin 81Mg Non-enteric coated Tab
    • one tab daily

Arms, Groups and Cohorts

  • Other: Aspirin
    • 81mg aspirin daily

Clinical Trial Outcome Measures

Primary Measures

  • salicylic acid level
    • Time Frame: 24 hour
    • time/concentration profile
  • serum thromboxane
    • Time Frame: 4 week post initiation
    • ELISA based quantification of serum thromboxane B2
  • PFA-100
    • Time Frame: 4 week post initiation
    • PFA-100 epi closure time (Siemens)

Secondary Measures

  • Urinary thromboxane
    • Time Frame: 4 week post initiation
    • ELISA based quantification of urindary dehydrothromboxane B2

Participating in This Clinical Trial

Inclusion Criteria

  • <16 weeks' gestational age – Singleton pregnancy – Plan to take 81mg aspirin due to high risk history (below), but not yet initiated – ≥1 risk factor: – Chronic hypertension – Type I or II diabetes – Previous preeclampsia – Renal disease – Autoimmune disease (SLE) OR ≥2 risk factor: – Nulliparity – IVF pregnancy – Black race or socioeconomic disadvantaged – BMI>30 – Prior adverse pregnancy outcome Exclusion Criteria:

  • Contraindication to aspirin – Current or planned use of any other anticoagulation – Current need for dialysis – Use of aspirin therapy prior to enrollment in the current pregnancy – Thrombocytopenia (<150) – Other known platelet disorder/thrombophilia at enrollment

Gender Eligibility: Female

Minimum Age: 13 Years

Maximum Age: 55 Years

Are Healthy Volunteers Accepted: No

Investigator Details

  • Lead Sponsor
    • Thomas Jefferson University
  • Collaborator
    • Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD)
  • Provider of Information About this Clinical Study
    • Sponsor
  • Overall Official(s)
    • Rupsa C Boelig, MD, Principal Investigator, Thomas Jefferson University

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