The present invention relates to a polypeptide comprising (a) a first set of six complementarity determining regions (CDRs) configured to bind a first antigen； and (b) (ba) a second set of six CDRs configured to bind a second antigen； or (bb) a ligand capable of binding to a second antigen； wherein (i) said first antigen is selected from Hepatitis B virus (HBV) small surface antigen； HBV medium surface antigen； and HBV large surface antigen； and (ii) said second antigen is selected from surface antigens presented by immune effector cells such as natural killer (NK) cells and cytotoxic T lymphocytes (CTLs). Also provided are compositions for use in a method of treating or preventing HBV infection and/or a condition caused by said HBV infection, said condition caused by said HBV infection being selected from liver cirrhosis and hepatocellular carcinoma.
