The study will primarily evaluate safety of the KNP-1000 apheresis system for pregnant women and their fetuses diagnosed with preeclampsia with severe features between 23- and 32-weeks' gestation (very preterm).
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.
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.