Immunogenic polypeptides comprising hepatitis C virus (HCV) immunogens are described. The HCV immunogen comprises the amino acid sequence Xaa-Thr-Xaa-Val-Thr-Gly-Gly-Xaa-Ala-Ala-Arg-Thr-Thr-Xaa-Gly-Xaa-Xaa-Ser-L- eu-P he-Xaa-Xaa-Gly-Xaa-Ser-Gln-Xaa-Ile-Gln-Leu-Ile (SEQ ID NO:8). The immunogenic polypeptide can be coupled to a bacterial toxoid, such as a diphtheria toxoid.