Study of MAR001 in Adults With Elevated Triglycerides and Remnant Cholesterol

The primary objective of the study is to evaluate the effect of MAR001 compared to placebo on levels of TG in adults with elevated TG and RC.

Inclusion Criteria: * Elevated fasting TGs and RC * Elevated nonfasting TGs and RC * Part A only: Fasting LDL-C ≥ 50 mg/dL (≥ 1.29 mmol/L) and ≤ 130 mg/dL (≤ 3.36 mmol/L) * Willingness to provide informed consent and comply with the intervention and all study assessments * Stable diet for a minimum of 3 months prior to screening and with no plans to change during screening or trial participation * Stable drug regimen (if relevant) prior to screening visit and no planned changes after enrollment; Part B only: adjustment of lipid-lowering therapy during the diet/lifestyle run-in period is permitted Exclusion Criteria: * Acute or chronic liver disease * Part A only: TG concentration ≥880mg/dl; Part B only: TG concentration ≥2000 mg/dL * History of type 1 diabetes mellitus or history of diabetic ketoacidosis * Newly diagnosed T2DM * Participants with known active hepatitis A, B, or C * Uncontrolled hypothyroidism * Part B only: recent history of active pancreatitis * Part B only: genetically confirmed Familial Chylomicronemia Syndrome (FCS) diagnosis due to biallelic loss of function mutations in LPL or GPIHBP1 * Part B only: use of ANGPTL3 and ApoC-III inhibitors * Any condition that prevents the participant from complying with study procedures