Elevated Apo B levels (>90 mg/100 mL) directly correlate with atherosclerotic cardiovascular disease (ASCVD) risk, outperforming LDL cholesterol as a predictor due to its one-to-one association with atherogenic particles. Mutations like APOB R3500Q cause familial hypercholesterolemia, impairing LDL receptor binding and increasing circulating LDL, leading to premature ASCVD. Apo B also contributes to insulin resistance and metabolic syndrome through pro-inflammatory pathways.

Clinically, Apo B serves as a nonfasting biomarker for residual cardiovascular risk, guiding therapies like mipomersen, an antisense oligonucleotide that reduces Apo B synthesis and LDL levels in refractory hypercholesterolemia. Emerging applications include targeting Apo B in lipoprotein(a) reduction and hepatic steatosis management.

Common uses include IVD standards, calibrators, and controls, lipid metabolism studies, biotherapeutic studies, antisera production.