The companies said that preliminary data from the trial of the drug GS 9132, did demonstrate antiviral activity and met the goal of the trial. This validates the mechanism that involves inhibition of a viral protein called NS4A, which binds to a portion of HCV protease.
“Even at the low dose studied, we observed significant reductions in hepatitis C viral load,” said Norbert Bischofberger, executive vice president, R&D, Gilead Sciences
However, based on small elevations of serum creatinine, a marker of kidney function, Gilead and Achillion have elected to shift their focus to the evaluation of other NS4A antagonists developed to identify a lead candidate for development.
As part of their collaboration Gilead and Achillion have been working to generate a number of compounds belonging to a different chemical class that demonstrate the same mechanism of action and similar in vitro potency to GS 9132.
One of the most promising of these, ACH-1095, is being developed with other compounds in preclinical studies to determine if one has the right profile to advance into clinical development.