HBV Advocate Blog: EASL 2015: Novira Therapeutics Announces Presentation of Preclinical Antiviral Data for NVR 3-778 at EASL

DOYLESTOWN, Pa., April 27, 2015 /PRNewswire/ -- Novira Therapeutics, Inc., a privately held, clinical-stage biopharmaceutical company developing novel therapies for curative treatment of chronic hepatitis B virus (HBV) infection, today announced the presentation of preclinical antiviral data for its lead HBV core inhibitor candidate, NVR 3-778, at the 2015 annual meeting of the European Association for the Study of the Liver (EASL) in Vienna, Austria.

The antiviral activity of NVR 3-778 from studies performed in a humanized UPA/SCID mouse model was described in an oral presentation. As monotherapy given for a six week duration, NVR 3-778 showed HBV DNA suppression efficacy superior to pegylated interferon (PEG-IFN) and similar to that of the widely prescribed nucleoside analog entecavir. All mice responded to treatment and there was no evidence for drug resistance. The highest efficacy was observed in mice that received NVR 3-778 in combination with PEG-IFN, where all treated mice (n=11) reduced serum HBV DNA below the limit of quantitation.

In a poster session, Novira presented results from the combination of NVR 3-778 with nucleoside analogs lamivudine, tenofovir or entecavir in a cell-based model. These data showed additive and synergistic antiviral activity without cytotoxicity. NVR 3-778 also showed additive antiviral activity in combination with an HBV core inhibitor from another chemical class.

"The apparent synergy of NVR 3-778 in combination with PEG-IFN is very encouraging. This is the first time that we have seen a treatment with higher DNA suppression efficacy than entecavir in a humanized mouse model," said Klaus Klumpp, Ph.D., Novira's VP of Discovery and Biology. "Having access to a new class of Direct Acting Antivirals, or DAAs, enables the clinical testing of combination treatments that may significantly intensify the suppression of HBV production in the liver. Highly potent DAA combination treatment may be able to reduce the rate of new hepatocyte infection below that of infected hepatocyte clearance in HBV infected patients and may thereby lead to a clinically-relevant improvement in functional cure rates."

NVR 3-778 is a small molecule, direct acting antiviral, for oral administration in patients with Chronic Hepatitis B (CHB) that inhibits the HBV core or capsid protein. HBV core is a novel and promising drug target with multiple activities required for viral replication and persistence. Inhibition of the HBV core protein function by NVR 3-778 offers the potential for more efficient suppression of virus production and replication, leading to improved durable viral suppression and functional cure rates. NVR 3-778 completed a Phase 1a clinical trial in 2014 and is currently enrolling a Phase 1b clinical trial.

Novira Therapeutics, Inc., is a privately held biopharmaceutical company focused on discovery and development of first-in-class antiviral drugs for the treatment of chronic HBV infection (CHB), a global disease with a high level of unmet medical need. The company is employing innovative chemistry and biology technologies to discover small molecule inhibitors of the HBV core or capsid protein as well as other drugs with novel mode of action. The company's novel antivirals will offer the potential to address the limitations of current CHB therapies when used either as mono-therapy or in combination with existing standards of care.