- 现金
- 62111 元
- 精华
- 26
- 帖子
- 30437
- 注册时间
- 2009-10-5
- 最后登录
- 2022-12-28
|
ContraVir (CTRV) Says CMX157 Data Reported at HEP DART Shows Enhanced in vitro Safety Profile vs Viread
ContraVir Pharmaceuticals, Inc. (NASDAQ: CTRV) reports positive results regarding CMX157's significantly enhanced potency against hepatitis B virus (HBV), now determined to be 97-fold compared to tenofovir (TFV), based on state-of-the-art in vitro studies. These results from head-to-head studies support CMX157's potential for an enhanced safety profile compared to Gilead's tenofovir DF (Viread®).
The data were presented at HEP DART 2015 by John Sullivan-Bolyai, MD, MPH, Chief Medical Officer of ContraVir, who stated, "These compelling results, derived from state-of-the-art in vitro studies, show that CMX157 potentially demonstrates equal, if not better, antiviral activity at low doses compared to Viread®. Furthermore, we've consistently shown that CMX157 not only has less cytotoxicity than Viread® in vitro along with a low potential for mitochondrial toxicity, but should significantly reduce the amount of TFV exposure outside the liver, further enhancing the safety profile of CMX157 compared to Viread®. These favorable results provide a solid foundation for advancing our Hepatitis B clinical program."
The presentation is available on the ContraVir website, www.contravir.com.
CMX157 demonstrates a potential enhanced safety profile compared to Viread® (Tenofovir DF, TDF)
CMX157 exhibited a low potential for mitochondrial toxicity in a standard assay of mitochondrial integrity under glucose vs. galactose growth conditions, confirming previous in vitro results.
CMX157 was less cytotoxic than TDF, based on IC50 concentrations that were consistently similar to or higher than TDF across a large panel of diverse cell lines.
CMX157 is 97-fold more active against HBV than TFV in vitro
Final results, from a greater number of experiments, improved upon earlier estimates of 60-fold greater potency of CMX157 compared to TFV.
The amount of drug required to inhibit HBV DNA in HepG2.2.15 liver cells was dramatically lower (EC50 = 15.03 +/- 4.31 nM) for CMX157 compared to TFV (EC50 1460 +/- 1127 nM).
CMX157 is highly liver targeted (rat model), limiting exposure of other tissues to TFV
After a single, oral dose, 86% of absorbed CMX157 was rapidly extracted by the liver.
Blood levels of CMX157 peaked at 1-3 hours and then declined rapidly, becoming undetectable after 6 hours; only low levels of TFV were detected in the peripheral circulation.
There was no substantial accumulation or retention in the heart following oral or intravenous administration.
CMX157 is rapidly and efficiently converted to the active antiviral, TFV diphosphate by liver cells, consistent with its improved antiviral activity and potential for dose reduction
CMX157 was efficiently metabolized by hepatocytes into active TFV diphosphate (TFV-PP).
CMX157 metabolism in vitro was time- and dose-dependent, yielding proportional levels of TFV and TFV-PP over time, during which liver cells remained fully viable.
CMX157 showed only minimal metabolism by cardiomyocytes in vitro compared to Viread®.
CMX157 exhibits low potential for drug-drug interactions
CMX157 did not exhibit significant induction/inhibition of key metabolic enzymes or transporters in vitro.
|
|