Low Molecular Weight Heparin for Blood Clot Prevention in Pregnancy

Overseen by Afshan Hameed, MD

Age: 18+

Sex: Female

Travel: May Be Covered

Time Reimbursement: Varies

Trial Phase: Phase 4

Recruiting

Sponsor: University of California, Irvine

Must be taking: Low molecular weight heparin

Disqualifiers: Multiples, Age under 18, HIT, others

No Placebo Group

Prior Safety Data

Approved in 3 Jurisdictions

Trial Summary

What is the purpose of this trial?

Pregnancy is associated with a increased risk of developing blood clots. There is nearly a 5 times greater risk of developing a blood clot in pregnancy. Lovenox is a medication that helps to prevent the body from developing clots. It is safe to use in pregnancy. Previous studies have demonstrated that despite recommendation of Lovenox, to prevent blood clots, the majority of patient's (70 to 90%) did not receive adequate levels of Lovenox at times throughout the day, which likely increases the risk of developing clots. The increase in blood volume and increase in kidney function that occurs in pregnancy may contribute to the inadequate levels. Currently the recommendation for pregnant and nonpregnant patients requiring Lovenox, is to calculate the daily dose of Lovenox and split the dose, giving half in the morning and the other half in the evening. This research study proposes that due to changes in the body during pregnancy that the daily Lovenox dosing be split into three times a day to achieve more consistent levels of Lovenox than twice a day in pregnant women.

Will I have to stop taking my current medications?

The trial information does not specify whether you need to stop taking your current medications. It focuses on adjusting the dosing schedule of Lovenox for pregnant women.

What data supports the effectiveness of the drug Lovenox (enoxaparin) for blood clot prevention in pregnancy?

Research shows that low molecular weight heparins like Lovenox are effective and safe for preventing blood clots in pregnant women, as they do not cross the placenta and have no harmful effects on the baby. They are also used successfully in other surgeries to prevent clots, suggesting their effectiveness in pregnancy. ^{1 2 3 4 5}

Is low molecular weight heparin safe for use in pregnancy?

Low molecular weight heparin, including enoxaparin (known by various names like Lovenox and Clexane), is generally considered safe for pregnant women, as it does not cross the placenta and has no harmful effects on the fetus. However, it should be used with caution in women with prosthetic heart valves and may need to be stopped before certain procedures like epidurals during labor. ^{1 2 5 6 7}

How is the drug Lovenox unique for preventing blood clots in pregnancy?

Lovenox (Enoxaparin) is unique because it is a low molecular weight heparin that reduces the risk of bleeding complications and does not cross the placenta, making it safe for use during pregnancy. It is administered subcutaneously (under the skin) once or twice daily, offering a convenient dosing schedule compared to other anticoagulants. ^{1 3 4 8 9}

Research Team

Afshan Hameed, MD

Principal Investigator

University of California, Irvine

Eligibility Criteria

This trial is for pregnant women aged 18 or older who need blood thinners to prevent clots and have a single baby in the womb. It's not for those under 18, with multiple babies, a history of bad reactions to heparin (HIT), or allergies to enoxaparin.

Inclusion Criteria

I am pregnant and need low molecular weight heparin for treatment.

I am 18 years old or older.

Exclusion Criteria

I am pregnant with more than one baby.

I am a woman under 18 years old.

History of Heparin Induced Thrombocytopenia (HIT)

Trial Timeline

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

Treatment

Participants receive therapeutic Lovenox dosing split into three times a day for 5 days

5 days

Follow-up

Participants are monitored for safety and effectiveness after treatment

4 weeks

Treatment Details

Interventions

• Lovenox (Anticoagulant)

Trial Overview The study tests if taking Lovenox three times daily instead of twice can maintain safer levels in pregnant women due to their body changes. The goal is consistent anticoagulation to reduce clot risks without over-thinning the blood.

Participant Groups

Group I: Factor Xa levels in pregnant women with therapeutic Lovenox divided into three times a day dosing Experimental Treatment 1 Intervention

Therapeutic Lovenox dosing split into three times a day dosing for 5 day. Xa levels a measured.

Lovenox is already approved in Canada for the following indications:

Approved in Canada as Lovenox for:

• Deep vein thrombosis
• Pulmonary embolism
• Acute coronary syndrome
• Heart attacks
• Prevention of blood clots in pregnancy

Who Is Running the Clinical Trial?

University of California, Irvine

Lead Sponsor

Trials

580

Recruited

4,943,000+

Chad T. Lefteris

University of California, Irvine

Chief Executive Officer since 2019

MBA from University of California, Irvine

Michael J. Stamos

University of California, Irvine

Chief Medical Officer since 2019

MD, PhD from University of California, Irvine

Findings from Research

Low molecular weight heparins (LMW heparins), like enoxaparin, are effective and safe for preventing thromboembolic complications in gynecologic surgery, with a reduced risk of bleeding and thrombocytopenia compared to standard heparin.

LMW heparins do not cross the placenta during any trimester and have no evidence of mutagenic or teratogenic effects, suggesting they are safe for use in pregnancy for thromboprophylaxis and treatment.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Low molecular weight heparins and their use in obstetrics and gynecology. Fejgin, MD., Lourwood, DL.[2019]

Lovenox (enoxaparin sodium) is considered safe and effective for pregnant women needing either preventive or treatment anticoagulation, based on its use in various clinical scenarios.

However, it is not recommended for pregnant women with prosthetic heart valves, and caution is advised when using it before epidural anesthesia during labor.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

ACOG Committee Opinion: safety of Lovenox in pregnancy. [2009]

In a study of 61 high-risk pregnant women receiving enoxaparin for thromboprophylaxis, there were no cases of antenatal thromboembolism, indicating its safety and efficacy in preventing blood clots during pregnancy.

While enoxaparin was effective in preventing thromboembolism, 32% of women showed reduced bone density post-partum, suggesting a need for further research on its long-term effects on bone health.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Low-molecular-weight heparin for obstetric thromboprophylaxis: experience of sixty-nine pregnancies in sixty-one women at high risk. Nelson-Piercy, C., Letsky, EA., de Swiet, M.[2019]

In a prospective study of 10 pregnant patients with Factor V Leiden mutation, daily administration of low molecular weight heparin (enoxaparin) resulted in no recorded cases of thrombosis or hemorrhage during pregnancy or delivery, indicating its safety and efficacy.

All infants born to the mothers in the study were healthy, and the continuation of enoxaparin postpartum for 6 to 12 weeks further supports its role as a potential gold standard for obstetric thromboprophylaxis.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

[Resistance to activated protein C and pregnancy: thromboprophylaxis with low molecular weight heparin]. Barjot, P., Beucher, G., Le Querrec, A., et al.[2006]

Lovenox (enoxaparin sodium) is considered safe and effective for pregnant women needing either preventive or treatment anticoagulation, based on its use in various clinical scenarios.

However, it is not recommended for pregnant women with prosthetic heart valves, and caution is advised when using it before epidural anesthesia during labor.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

ACOG committee opinion. Safety of Lovenox in pregnancy. Number 276, October 2002. Committee on Obstetric Practice. [2019]

Enoxaparin, a low-molecular-weight heparin, is the preferred anticoagulant during pregnancy, effectively preventing venous thromboembolism and pregnancy complications without crossing the placenta, making it safe for the fetus.

The medication has a low incidence of maternal side effects, primarily mild allergic reactions and increased bleeding, and its mechanisms of action include anti-factor Xa activity and anti-inflammatory effects, which contribute to its efficacy in pregnant women.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Enoxaparin use in pregnancy: state of the art. Brenner, B.[2016]

Enoxaparin, a low molecular weight heparin, is effective for preventing venous thromboembolism (VTE) in nonsurgical patients with limited mobility due to acute illness, showing similar efficacy to unfractionated heparin but with the convenience of once-daily dosing.

Enoxaparin has a favorable tolerability profile, with lower incidences of local hematomas and increased liver enzymes compared to unfractionated heparin, making it a cost-effective option for short-term VTE prophylaxis.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Enoxaparin: a review of its use as thromboprophylaxis in acutely ill, nonsurgical patients. Siddiqui, MA., Wagstaff, AJ.[2018]

Recent clinical studies have shown that acutely ill medical patients are at a high risk for venous thromboembolism, a serious condition that can lead to blood clots.

Thromboprophylaxis using low molecular weight heparin, specifically enoxaparin, has been approved to effectively reduce this risk in bedridden patients due to acute illness.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Thromboprophylaxis in medical patients. Hampton, KK.[2019]

In critically ill trauma patients, particularly those with significant peripheral edema, the standard dose of enoxaparin (30 mg every 12 hours) resulted in significantly lower anti-Xa activity, indicating reduced efficacy in preventing venous thromboembolism (VTE).

The variability in anti-Xa activity was high, with many edematous patients showing barely quantifiable results, suggesting that the standard dosing may not be reliable for this patient population.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Pharmacokinetics and pharmacodynamics of enoxaparin in multiple trauma patients. Haas, CE., Nelsen, JL., Raghavendran, K., et al.[2019]

References

1. United States pubmed.ncbi.nlm.nih.gov

Low molecular weight heparins and their use in obstetrics and gynecology. [2019]

2. United States pubmed.ncbi.nlm.nih.gov

ACOG Committee Opinion: safety of Lovenox in pregnancy. [2009]

3. United States pubmed.ncbi.nlm.nih.gov

Low-molecular-weight heparin for obstetric thromboprophylaxis: experience of sixty-nine pregnancies in sixty-one women at high risk. [2019]

4. France pubmed.ncbi.nlm.nih.gov

[Resistance to activated protein C and pregnancy: thromboprophylaxis with low molecular weight heparin]. [2006]

5. United States pubmed.ncbi.nlm.nih.gov

ACOG committee opinion. Safety of Lovenox in pregnancy. Number 276, October 2002. Committee on Obstetric Practice. [2019]

6. United States pubmed.ncbi.nlm.nih.gov

Enoxaparin use in pregnancy: state of the art. [2016]

7. New Zealand pubmed.ncbi.nlm.nih.gov

Enoxaparin: a review of its use as thromboprophylaxis in acutely ill, nonsurgical patients. [2018]

8. England pubmed.ncbi.nlm.nih.gov

Thromboprophylaxis in medical patients. [2019]

9. United States pubmed.ncbi.nlm.nih.gov

Pharmacokinetics and pharmacodynamics of enoxaparin in multiple trauma patients. [2019]