Achillion Pharmaceuticals has reported that 94% to 100% of treatment naïve genotype 1 chronic hepatitis C virus (HCV) patients achieved a complete early virologic response (cEVR) after 12 weeks of treatment with its ACH-1625 in combination with pegylated interferon alfa-2a and ribavirin (P/R) in Segment 2 of a Phase 2a trial.
ACH-1625 is an open chain, non-covalent, Phase 2 pan-genotypic HCV protease inhibitor designed and synthesised based on crystal structures of enzyme/inhibitor complex.
In the second segment of the Phase 2a trial, a total of 58 subjects with HCV were randomised and stratified by IL28B genotype to receive one of three doses of once-daily ACH-1625 (200mg, 400mg or 800mg) in combination with P/R for 12 weeks of therapy.
Following 12 weeks of treatment, ACH-1625 in combination with P/R was found to be safe and well tolerated, and produced high viral response rates regardless of dose level or IL28B genotype status.
Achillion president and chief executive officer Michael Kishbauch said the company is pleased with the safety, efficacy as well as the resistance profile that ACH-1625 has demonstrated in the Phase 2 clinical trial.
"As we finalise this Phase 2 trial and report on SVR later this year, we are now focused on initiating our all-oral program for the treatment of HCV," Kishbauch added.
"With the recent submission of an IND for ACH-3102, our second-generation NS5A inhibitor, we look forward to initiating its Phase 1 program this quarter and rapidly advancing toward a therapeutic, interferon-free combination trial evaluating ACH-1625 plus ACH-3102 during the fourth quarter of this year."
In preclinical studies, ACH-1625 showed rapid and extensive partitioning to the liver, as well as high liver/plasma ratios, low single-digit nanomolar potency that is specific to HCV.
Achillion chief medical officer Elizabeth Olek said the clinical potency, pharmacokinetic profile, and barrier to resistance for ACH-1625 found to provide effective antiviral coverage for all the genotype 1 patients.
"With the continued on-treatment viral suppression and impressive initial end of treatment response rates, we look forward to reporting out the sustained viral response rates for these patients later in the year," Olek added.