Disclosed is a composition for use in inhibiting expression of a target gene within a target cell, the composition comprising: - a nucleic acid molecule that effects RNAi of a target gene - a chimeric antigen comprising: a nucleic acid binding domain comprising an amino acid sequence corresponding to HBV core protein or a functional fragment thereof, and a target binding domain comprising a ligand for binding to a receptor on a target cell. Further disclosed is a composition for use in silencing the expression of a target gene within a target cell, the composition comprising: a nucleic acid sequence corresponding to the target gene and a chimeric antigen comprising a nucleic acid interaction domain corresponding to HBV core protein or a functional fragment thereof, and a target binding domain operatively attached to the nucleic acid interaction domain, the target binding domain comprising a ligand for binding to a receptor on the surface of the target cell.
