PostpartumPhase 1LACTNCT06831474
Excretion of Rivaroxaban in Human Breast Milk
A Phase 1 study testing Rivaroxaban 10 MG Oral Tablet and Rivaroxaban 20 MG Oral Tablet in people with Postpartum and VTE Prophylaxis, run by Thomas Jefferson University at 1 site in United States.
Trial summary
The purpose of this study is to investigate the distribution of rivaroxaban into human milk at both therapeutic and prophylactic doses, and over time with repeated dosing. Read more about this study
- Who is it for?
- Ages 18 years and older, women only
- Conditions the study is for
- Postpartum, VTE Prophylaxis, VTE (Venous Thromboembolism)
- What is being tested?
- Rivaroxaban 10 MG Oral Tablet and Rivaroxaban 20 MG Oral Tablet
- Type of treatment
- Pill or oral medicine
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 10 participants
- Where
- 1 siteUnited States
- Study dates
- Jul 2025to 31 Jul 2026
- Phase
- Phase 1
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
- Postpartum within 6 weeks of delivery
- Greater than 18 years old at expected date of delivery
- English speaking
- Hemodynamically stable without concern for ongoing blood loss
- Non-breastfeeding
- Or breastfeeding an infant born at or equal to 37 weeks' gestation, weighing >2600g at birth and is not requiring intensive care
- Meet inclusion criteria for prophylactic rivaroxaban dose: pre-pregnancy BMI >/= 40 and/or any personal history of VTE. Or >/= 2 of the following: pre-pregnancy BMI 30-39, immobility, pregnancy complications, cesarean delivery, hysterectomy
- Or meet inclusion criteria for therapeutic rivaroxaban dose: have an indication for therapeutic anticoagulation per the American College of Obstetricians and Gynecologists' (ACOG) practice bulletin #196, or other indication per their primary team, and recommended for such anticoagulation per their primary practitioner.
Who cannot join
- Pregnant
- Less than 18 years old at estimated date of delivery
- Hemodynamic instability and/or concern for ongoing blood loss
- Newly diagnosed deep vein thrombosis (DVT) or pulmonary embolism (PE) in the postpartum period
- Abnormal maternal renal or liver function (creatinine clearance < 30 mL/min and/or liver function tests greater than lab normal)
- A contraindication to rivaroxaban: hypersensitivity to rivaroxaban; active pathological bleeding
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- Breastfeeding an infant admitted to neonatal intensive care unit, infant gestational age at birth <37w0d or weighing <2600g.
- If all of the following are met: age less than 40, ambulating, body mass index (BMI) less than 30, no active history of malignancy.
- If patient lacks indication for therapeutic anticoagulation in the postpartum period per the American College of Obstetricians and Gynecologists' (ACOG) practice bulletin #196
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
United States1 site, 1 recruiting
- Recruiting
Thomas Jefferson University Hospital
Philadelphia, Pennsylvania, 19107
Sophie Green, MD, 215-955-5000, sophie.green@jefferson.edu
Rupsa C Boelig, MD
About this study
The purpose of this study is to investigate the distribution of rivaroxaban into human milk at both therapeutic and prophylactic doses, and over time with repeated dosing.
Read the detailed description
The aim of our study is to perform a phase 1, single arm clinical trial to investigate the distribution of rivaroxaban into human milk at both therapeutic and prophylactic maternal doses. Our goal is to enhance the limited, although positive, data regarding the safety of rivaroxaban in breastfeeding. Our novel contributions to the existing body of literature will be in our investigation of rivaroxaban at both prophylactic and therapeutic doses, in repeated doses over time, and in a larger sample of participants. These results will provide physicians and national societies with safety data needed to properly counsel patients and advance clinical guidelines for postpartum care.
- Conditions
- Postpartum, VTE Prophylaxis, VTE (Venous Thromboembolism), Rivaroxaban, Breastfeeding, Breast Milk Collection
- Being tested
- Rivaroxaban 10 MG Oral Tablet, Rivaroxaban 20 MG Oral Tablet
- Keywords
- Rivaroxaban, Relative infant dose, LACT, Rivaroxaban in breast milk
- Medical subject headings
- Venous Thromboembolism, Breast Feeding, Breast Milk Expression
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Rivaroxaban 10 MG Oral TabletDrug
Also called Xarelto
10mg rivaroxaban daily
Rivaroxaban 20 MG Oral TabletDrug
20mg rivaroxaban daily
| Study group | Role | What they receive |
|---|---|---|
| Prophylactic rivaroxaban | Active comparator | Patients will receive 10 mg daily of rivaroxaban starting by the first postpartum day. The medication will be ordered by their postpartum physician team through the inpatient pharmacy and dispensed by their inpatient nursing team, as per standard of care. The decision for dose 10 mg vs 20 mg of rivaroxaban is based on inclusion criteria and patient's physician team's recommendation for prophylactic (10 mg) vs. therapeutic (20 mg) dosing. Receives: Drug: Rivaroxaban 10 MG Oral Tablet |
| Therapeutic or Intermediate dose rivaroxaban | Active comparator | Patients will receive 20 mg daily of rivaroxaban starting by the first postpartum day. The medication will be ordered by their postpartum physician team through the inpatient pharmacy and dispensed by their inpatient nursing team, as per standard of care. The decision for 10 mg vs 20 mg of rivaroxaban is based on inclusion criteria and patient's physician team's recommendation for prophylactic (10 mg) vs. therapeutic (20 mg) dosing. Receives: Drug: Rivaroxaban 20 MG Oral Tablet |
What is being measured
The primary outcome is the main question the study is designed to answer.
Concentration of rivaroxaban in breast milk
Time/Concentration profile of rivaroxaban in breast milk prior to intake (0) and 3, 6, 12, 15 and 24 hours following morning dose on day 0-1
Measured: Postpartum day 1
Concentration of rivaroxaban in breast milk
Time/concentration profile of rivaroxaban in breast milk 3 hours following morning dose on day 2 and onward
Measured: Postpartum week 6
Absolute infant dose of rivaroxaban
The absolute infant dose is calculated from average drug concentrations in breast milk multiplied by an estimated breast milk intake of 150 mL/kg/day.
Measured: 6 week postpartum
Relative infant dose
The relative infant dose is the absolute infant dose expressed as a percentage of the weight adjusted maternal dose, based on an average maternal weight of 75 kg. It is expressed in mg/kg/day.
Measured: 6 weeks postpartum
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted18 Feb 2025
- Study startJul 2025 (estimated)
- Primary completion1 Apr 2026 (estimated)
- Study completion31 Jul 2026 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (9)Papers the sponsor has linked to this study.
- Other trials for PostpartumStudies of the same condition, open and under way.
- 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 1
- Primary purpose
- Prevention
- Allocation
- Non-randomised
- Intervention model
- Parallel groups
- Model description
- This is a prospective phase 1, two arm drug trial comparing the excretion of rivaroxaban in human breast milk between groups receiving prophylactic or therapeutic dosing during the postpartum period. Patients will be screened and enrolled for participation either antepartum or postpartum. Once postpartum, patients will be re-screened for any exclusion criteria and to be sure all inclusion criteria is met. Prior to receiving rivaroxaban each patient will provide a baseline 1 mL breast milk sample. Patients will either receive 10 mg or 20 mg daily of rivaroxaban starting by the first postpartum day. The dose will be be ordered by their postpartum physician team through the inpatient pharmacy and dispensed by their inpatient nursing team, as per standard of care at the discretion of their physician. 1 mL of breast milk will be collected at 3, 6, 12, 15 and 24 hours following their first morning dose. The patient will continue the medication while in house and for each subsequent day o
- Masking
- None (open label)
- Enrolment
- 10 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Thomas Jefferson University
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Rupsa C. Boelig, Thomas Jefferson University
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT06831474
- Sponsor's protocol ID
- iRISID-2025-0397
- Acronym
- LACT
- Status last verified
- Jul 2025
- First submitted
- 12 Feb 2025
- Last updated
- 17 Jul 2025
- Results posted
- No
- Data monitoring committee
- Yes
- FDA-regulated drug
- Yes
- FDA-regulated device
- No
- Individual data sharing
- No: The participant data will be kept confidential and access will be limited to the study investigators in order to respect the privacy of the participants.
Publications
Male C, Lensing AWA, Palumbo JS, Kumar R, Nurmeev I, Hege K, Bonnet D, Connor P, Hooimeijer HL, Torres M, Chan AKC, Kenet G, Holzhauer S, Santamaria A, Amedro P, Chalmers E, Simioni P, Bhat RV, Yee DL, Lvova O, Beyer-Westendorf J, Biss TT, Martinelli I, Saracco P, Peters M, Kallay K, Gauger CA, Massicotte MP, Young G, Pap AF, Majumder M, Smith WT, Heubach JF, Berkowitz SD, Thelen K, Kubitza D, Crowther M, Prins MH, Monagle P; EINSTEIN-Jr Phase 3 Investigators. Rivaroxaban compared with standard anticoagulants for the treatment of acute venous thromboembolism in children: a randomised, controlled, phase 3 trial. Lancet Haematol. 2020 Jan;7(1):e18-e27. doi: 10.1016/S2352-3026(19)30219-4. Epub 2019 Nov 5.
PubMed 31699660Muysson M, Marshall K, Datta P, Rewers-Felkins K, Baker T, Hale TW. Rivaroxaban Treatment in Two Breastfeeding Mothers: A Case Series. Breastfeed Med. 2020 Jan;15(1):41-43. doi: 10.1089/bfm.2019.0124. Epub 2019 Sep 18.
PubMed 31532233Saito J, Kaneko K, Yakuwa N, Kawasaki H, Yamatani A, Murashima A. Rivaroxaban Concentration in Breast Milk During Breastfeeding: A Case Study. Breastfeed Med. 2019 Dec;14(10):748-751. doi: 10.1089/bfm.2019.0230. Epub 2019 Nov 20.
PubMed 31746638Wiesen MH, Blaich C, Muller C, Streichert T, Pfister R, Michels G. The Direct Factor Xa Inhibitor Rivaroxaban Passes Into Human Breast Milk. Chest. 2016 Jul;150(1):e1-4. doi: 10.1016/j.chest.2016.01.021.
PubMed 27396794Zhao Y, Arya R, Couchman L, Patel JP. Are apixaban and rivaroxaban distributed into human breast milk to clinically relevant concentrations? Blood. 2020 Oct 8;136(15):1783-1785. doi: 10.1182/blood.2020006231. No abstract available.
PubMed 32488251Bennett PN, ed. Drugs and human lactation, 2nd ed. Amsterdam. Elsevier. 1996.
Lanitis T, Leipold R, Hamilton M, Rublee D, Quon P, Browne C, Cohen AT. Cost-effectiveness of Apixaban Versus Other Oral Anticoagulants for the Initial Treatment of Venous Thromboembolism and Prevention of Recurrence. Clin Ther. 2016 Mar;38(3):478-93.e1-16. doi: 10.1016/j.clinthera.2016.01.020. Epub 2016 Feb 26.
PubMed 26922297Guillonneau M, de Crepy A, Aufrant C, Hurtaud-Roux MF, Jacqz-Aigrain E. [Breast-feeding is possible in case of maternal treatment with enoxaparin]. Arch Pediatr. 1996 May;3(5):513-4. doi: 10.1016/0929-693x(96)86421-9. No abstract available. French.
PubMed 8763733American College of Obstetricians and Gynecologists' Committee on Practice Bulletins-Obstetrics. ACOG Practice Bulletin No. 196: Thromboembolism in Pregnancy. Obstet Gynecol. 2018 Jul;132(1):e1-e17. doi: 10.1097/AOG.0000000000002706.
PubMed 29939938