Press Release

REP 2139 and TDF/ETV combine synergistically to establish control of cccDNA in the liver

MONTREAL, December 20, 2017 – Replicor Inc., a privately held biopharmaceutical company targeting a functional cure for patients with chronic HBV infection and HBV / HDV co-infection announced today the publication of its in vivo study examining the efficacy of REP 2139 combined with tenofovir disoproxil fumarate (TDF) or TDF and entecavir (ETV) in the journal Hepatology.


Conducted in collaboration with Dr. Lucyna Cova at the Institut National de Santé et Recherche Médicale (INSERM) U1052 in Lyon, France, this study examined the antiviral effects of combined therapy with the nucleic acid polymer (NAP) REP 2139 and TDF or TDF and ETV in the duck model of HBV infection. Several previously published studies have demonstrated the utility of this animal model to reliably predict the effects of NAPs in clinical studies, with the most recent of these studies indicating that the production of HBV subviral particles in human infection, the targeting of which is critical for achieving functional remission of HBV infection, are also uniquely reproduced in this model.


In the current study, combining REP 2139 with TDF or TDF and ETV produced a synergistically enhanced antiviral response, with faster on-treatment clearance of surface antigen and viral DNA, increased rates of functional remission of hepadnaviral infection after removal of therapy and most importantly, clearance of surface antigen from the liver and a synergistic enhancement in the inactivation and/or clearance of cccDNA in the liver after removal of therapy, findings which were verified by Southern blot.

Dr. Andrew Vaillant, CSO of Replicor commented, “We are excited by these findings as they clearly suggest that combining REP 2139 with TDF, ETV or other latest generation tenofovir derivatives, such as tenofovir alafenamide and tenofovir exalidex, will have a synergistic effect on establishing control of cccDNA in the liver in the absence of immunotherapy. These results suggest that the functional remission of HBV infection, which we can now achieve in patients with finite therapy with REP 2139, TDF and pegylated interferon, may be achievable in some patients in the absence of immunotherapy.”

About Replicor
Replicor is a privately held biopharmaceutical company with the most advanced animal and human clinical data in the development of a functional cure for HBV and HDV. The company is dedicated to accelerating the development of an effective treatment for patients with HBV and HBV/HDV co-infection. For further information about Replicor please visit our website at

Media Contact:
Natacha Dorget
(514) 733-1998