HCV clearance by direct-acting antivirals reduces serum phosphatidylethanolamine and improves phospholipid balance

Phosphatidylethanolamine (PE) contributes to hepatitis C virus (HCV) replication. Although direct-acting antivirals (DAAs) achieve rapid viral clearance and normalize circulating lipid abnormalities, their effects on the serum PE profile remain incompletely defined. We longitudinally investigated 18 serum PE species during DAA therapy in 178 patients with chronic HCV infection. PE species were quantified using direct-flow injection tandem mass spectrometry on a triple-quadrupole platform. Samples were collected before treatment and at weeks 4 and 12 of DAA therapy. DAA therapy was associated with declines in PE 36:4, PE 38:4, 38:6, 40:5, and 40:6, as well as total serum PE. In parallel, the serum phosphatidylcholine-to-phosphatidylethanolamine (PC/PE) ratio increased. Most PE species, total PE levels, and the PC/PE ratio did not correlate with routine laboratory markers of liver disease or with the Model for End-Stage Liver Disease score. Consistent with this, total PE levels and the PC/PE ratio were similar in patients with and without cirrhosis at the end of treatment. However, cirrhosis was associated with higher PE 36:3 and lower PE 38:4, 38:6, and 40:6. Patients infected with HCV genotype 3a had lower levels of eight PE species and lower total PE, whereas the PC/PE ratio was unchanged. These genotype-associated differences were no longer evident by the end of therapy. In summary, HCV clearance with DAA therapy is associated with marked remodeling of the serum PE profile, characterized by lower total PE levels and an improved PC/PE ratio. These findings suggest circulating phospholipid levels approaching normal after viral eradication.