Inclusion Criteria:
A participant is deemed suitable for inclusion in the investigation if she meets the following criteria:
- Pregnant woman ≥ 23 0/7 and < 32 0/7 weeks gestation, aged 18 to 45 years, hospitalized for preeclampsia at time of enrollment.
- Severe hypertension ever defined by resting systolic BP ≥ 160 mm Hg and/or diastolic BP ≥ 110 mm Hg on two occasions measured at least 4 hours apart.
- Proteinuria, defined as ≥ 300 mg protein in a 24-hour urine collection or ≥ 0.3 protein/creatinine ratio.
- Provision of signed and dated informed consent form.
Exclusion Criteria:
A participant will be excluded from the investigation if any of the following maternal or fetal criteria are met.
Maternal Exclusion Criteria:
- Documented history of chronic hypertension, defined as systolic BP ≥ 140mmHg and/or systolic BP ≥ 90 mmHg before pregnancy or prior to 20 weeks of gestation.
- Documented history of proteinuria prior to pregnancy or prior to 20 weeks of gestation.
- Taking any form of angiotensin cascade blocker or angiotensin-converting enzyme (ACE) inhibitor at time of enrollment.
- Documented history of cardiac impairments including uncontrolled arrhythmia, unstable angina, decompensated congestive heart failure, or valvular disease.
- Actively receiving therapeutic anticoagulation therapy or within the therapeutic window after ceasing anticoagulation therapy at the time of enrollment.
- Any condition which, in the opinion of the Investigator, would necessitate immediate delivery within 24 hours.
- Signs or history of cerebral nervous system dysfunction, including seizures, cerebral edema (previously confirmed by computed tomography scan or magnetic resonance imaging per medical records).
- Confirmed or suspected diagnosis of pulmonary edema at time of enrollment.
- Diagnosis of HELLP syndrome.
- Thrombocytopenia (platelet count < 100,000/mm3) at time of enrollment.
- Anemia defined as hemoglobin < 8 g/dL at time of enrollment.
- Absent or reverse flow on umbilical Doppler ultrasound exam at the time of screening, or documented history of negative or reverse flow during the current gestation period.
- Diagnosis of placenta previa during the current gestation period.
- Preterm labor at or before time of screening.
- Documented medical history of active hepatitis B virus, hepatitis C virus (HCV), syphilis, tuberculosis infection, or human immunodeficiency virus (HIV) positive status.
- Any condition that the Investigator deems a risk to the study participant or fetus in completing the investigation.
- Hypersensitivity to dextran sulfate cellulose or heparin.
- Multiple gestation.
- Documented history of familial hypercholesterolemia.
- Suspicion or diagnosis of placental abruption during the current gestation.
- Patients who have received the drug treatment not recommended by the American College of Obstetricians and Gynecologists (ACOG) practice bulletin Gestational Hypertension and Preeclampsia (the clinical management guidelines) within 6 months prior to enrollment.
- Patients who have participated in another clinical trial within 6 months prior to enrollment.
Fetal Exclusion Criteria:
- Documented record of chromosomal anomalies.
- Identifiable structural fetal abnormalities present at time of screening or a record of such abnormalities prior to enrollment.
- Oligohydramnios, defined as Amniotic fluid index (AFI) less than 5 cm when measured using the four-quadrant method at time of enrollment.
- Fetal growth restriction (FGR) defined as estimated fetal weight (EFW) below the 5th percentile for gestational age.