November 2006 saw Arrow’s first hepatitis C compound, A-831, enter phase I trials. Both compounds target the novel NS5a protein but have completely different chemical structures and bind to the target at different sites.
According to Arrow, the compound has shown highly potent activity in the replicon assay and has an excellent therapeutic index and good pharmacokinetic properties. Phase I trials on A-689 are planned for the second half of 2007.
The current standard of care treatment for hepatitis C, pegylated interferon plus ribavirin has a poor side effect profile and is only effective in around 50% of patients. Multiple drugs in combination therapy are likely to be needed to overcome drug resistance.
“We regard both our compounds as ideal components of the multiple drug combinations likely to be required to successfully treat this virus with its tendency to mutate and to resist new agents,” said Arrow’s CEO, Ken Powell.