ContraVir Pharmaceuticals, Inc., a biopharmaceutical company focused on the development and commercialisation of targeted antiviral therapies, announced preliminary data dramatizing the unique properties of CMX157, the company's highly potent lipid prodrug of the successful antiviral drug tenofovir (TFV).

CMX157 was shown to be 60-fold more active than tenofovir against the hepatitis B virus (HBV) based on in vitro studies. This significant potency difference has considerable potential in increasing the safety profile and reducing the side effects compared to tenofovir DF (Viread).

The company believes CMX157's lipid-conjugate design clearly differentiates it from tenofovir DF. ContraVir plans to file an investigational new drug (IND) application for CMX157 to treat HBV before year-end 2015. CMX157 benefits from earlier human studies in volunteers under an IND for HIV. ContraVir is focused on a quick evaluation of CMX157 in a phase 2 clinical study in patients with hepatitis B which it plans to begin in 2016.

CMX157's enhanced absorption technology which utilises the natural lipid uptake pathway to target the liver has the potential to lower systemic exposure compared to tenofovir, resulting in reduced off-target toxicity. Other studies with CMX157 are examining the efficiency of CMX157 prodrug conversion to the active antiviral, tenofovir diphosphate, within targeted hepatocytes, and further assessing the in vitro safety profile of CMX157, including a comprehensive evaluation of the likelihood of drug-drug interactions.

The United States is expected to see more than a 15 per cent rise in hepatitis B patients through 2033 and there are about 350 million chronic HBV patients worldwide. ContraVir is committed to meeting its timelines so that the company is positioned to treat these patients and capture this attractive and growing market.

CMX157 is a novel lipid acyclic nucleoside phosphonate that delivers high intracellular concentrations of the active antiviral agent tenofovir diphosphate. Compared to tenofovir, CMX157 is up to 60-fold more active against HBV and more than 200-fold more active against all major HIV subtypes in vitro. CMX157's novel structure results in decreased circulating levels of tenofovir, lowering systemic exposure and thereby reducing the potential for renal and bone side effects. It has completed a phase 1 clinical trial in healthy volunteers, demonstrating a favorable safety, tolerability and drug distribution profile.