APOB and metabolic dysfunction-associated steatotic liver disease: However, our results also suggest caution with therapeutics that reduce hepatic lipoprotein secretion: aggregated ultra-rare APOB variants that reduced serum apoB were positively associated with both MASLD and fibrosis, and a phase 3 study of an apoB synthesis inhibitor (mipomersen) resulted in increased steatosis and liver enzymes in several patients [90, 91].