HDL Acute Lipid Optimization in Homozygous Familial Hypercholesterolemia

Key Inclusion Criteria: * Clinical diagnosis of Homozygous Familial Hypercholesterolemia (HoFH) due to a defect in the LDL receptor, or the identification of a defect in apoB-100, or a gain of function of PCSK9, or a genetic defect resulting in the HoFH clinical phenotype * No other condition that would preclude the subject from successfully completing the series of plasmapheresis visits in the investigator's opinion * At least one (1) coronary artery study segment will be identified for each subject and all will remain constant throughout the study. The qualifying study segment(s) will have 20% to 40% stenosis. Key Exclusion Criteria: * Planned change in current lipid lowering therapy * Use of oral anticoagulants, unless the dose has been stable for 4 weeks * LDL or plasma apheresis within 1 week prior to enrollment and through 8-week primary endpoint * New York Heart Association (NYHA) class III or IV or last known left ventricular ejection fraction \< 30% * Myocardial infarction, unstable angina, percutaneous coronary intervention (PCI), coronary artery bypass graft (CABG) or stroke within 3 months of enrollment