An application has been filed with Japanese regulators by AbbVie for approval to market its direct-acting antiviral regimen of paritaprevir/ritonavir and ombitasvir for use in patients with hepatitis C genotype 1 infection. The filing was based on late-stage trial data that showed 95% of HCV genotype 1b patients achieved sustained virologic response after 12 weeks of therapy.
The FDA has notified Merck that the agency plans to withdraw the breakthrough-therapy designation granted to its hepatitis C drug, a combination of grazoprevir and elbasvir, because of the availability of other approved treatments for HCV genotype 1 infection. Merck said it will meet with FDA authorities to discuss the matter, but it will proceed with its plans to submit the regimen for FDA review in the next few months.
Merck & Co. agreed to pay about $3.85 billion to purchase Idenix Pharmaceuticals. The deal will further strengthen Merck's hepatitis C pipeline as the company will gain rights to Idenix's three clinical-stage hepatitis C virus treatments. Merck plans to combine the most promising drugs from Idenix and its own pipeline to develop a more effective treatment for hepatitis C.
A late-stage trial showed AbbVie's all-oral hepatitis C regimen cured 96% of patients with genotype 1 virus after only 12 weeks of therapy. Results of this trial, which involved patients who didn't respond to prior treatments, resembled the outcome of another Phase III study released last month that tested the regimen in previously untreated patients. The hepatitis C regimen, which contains three investigational antiviral drugs and ribavirin, is being tested in four more Phase III trials.
The FDA granted priority-review status to Janssen Research & Development and Medivir's experimental drug simeprevir as a treatment for genotype 1 chronic hepatitis C. Janssen said the FDA is likely to make a final decision this year. Simeprevir, intended to be taken with pegylated interferon and ribavirin, inhibits the protease enzyme that allows the virus to reproduce itself inside cells.