Findings strengthen promise of SCYNEXIS' SCY-635 for HCV treatment

Drug discovery company SCYNEXIS, Inc. today presented data supporting an impressive resistance profile for SCY-635—a novel, oral cyclophilin inhibitor being studied for the treatment of hepatitis C virus (HCV) infection. In the study, SCYNEXIS demonstrated that the hepatitis C virus required multiple mutations across two separate proteins in order to establish resistance to SCY-635. The majority of HCV drugs on the market and in development require only one targeted viral mutation to establish resistance. The results were presented in an oral session entitled, "Resistance Selection Following 15 Days of Monotherapy with SCY-635 a Non-immunosuppressive Cyclophilin Inhibitor with Potent Anti-HCV Activity," at the 45th Annual Meeting of the European Association for the Study of the Liver (EASL) in Vienna, Austria.

“There is a significant need for more effective treatments for HCV that work for a broader patient population and help overcome resistance issues”

"These latest findings greatly strengthen the promise of SCY-635 as an important new drug candidate for the treatment of HCV," said Sam Hopkins, PhD, Chief Scientific Officer of SCYNEXIS. "Over the year, we have established that single-agent treatment with SCY-635 yields a clinically meaningful reduction in viral load while exhibiting a very favorable safety profile. We have shown that SCY-635 exhibits additive to synergistic antiviral activity when combined with both approved and leading investigational agents and now we have demonstrated that SCY-635 appears to present the hepatitis C virus with a much a higher barrier to resistance than current therapies in development."

Previous Phase 1b studies demonstrated that single-agent SCY-635 was associated with a clinically meaningful decline in plasma viremia (group mean maximum decrease of 2.3 log10) and that the mean maximal decline was observed on the last day of the study, day 15, suggesting a high barrier to the development of viral resistance. For the resistance studies presented at EASL, SCYNEXIS conducted an in-depth analysis of samples of plasma virus from individuals who participated in the Phase 1b study to assess the extent to which prolonged SCY-635 monotherapy treatment is associated with markers of drug resistance.

Participants had either received placebo>in vitro studies which also indicate that multiple mutations in NS5A and NS5B are required to confer high level resistance to SCY-635.

"There is a significant need for more effective treatments for HCV that work for a broader patient population and help overcome resistance issues," said Yves J. Ribeill, PhD, President and Chief Executive Officer of SCYNEXIS. "We become more confident every day that SCY-635 could play an important role in establishing a new standard of care for a wider spectrum of HCV patients and look forward to continuing studies to this end. SCYNEXIS will initiate a Phase 2a study of SCY-635 in treatment naïve genotype 1 HCV patients in combination with the standard of care in the second quarter of 2010 and we anticipate top-line results from this study by year-end."

Source SCYNEXIS