Investigational drugs in development for Hepatitis D.

INTRODUCTION: Treatment of chronic hepatitis D still relies on Interferon. To improve efficacy, new therapeutic strategies are in development which aim to deprive the Hepatitis D Virus (HDV) of functions of the Hepatitis B Virus and of the host required for its life-cycle. Areas covered: The therapeutic options are; 1) The inhibition of the farnesylation of the large HD-protein permissive of virion assembly with Lonafarnib, 2) The blocking of HBsAg entry into cells with Myrcludex B via the inhibition of the Sodium Taurocholate Cotransporting Receptor, to prevent the spreading of HDV to uninfected hepatocytes, 3) The reduction of subviral HBsAg particles by REP 2139, leading to diminished virion morphogenesis . Expert opinion: Lonafarnib and Myrcludex reduced serum HVD-RNA; neither diminished serum HBsAg. NAP REP-2139 diminished both HDV-RNA and HBsAg in serum; a full report is awaited. In combination with Peg-Interferon, these new drugs may provide additional efficacy.