FDA to retract breakthrough therapy designation of grazoprevir/elbasvir combo for HCV

The FDA plans to retract breakthrough therapy designation status for the combination regimen of grazoprevir and elbasvir to treat chronic hepatitis C virus infection, according to 2014 financial results released by Merck.

According to the financial report available on the Merck website, Merck received notification from the FDA on Jan. 30 of its intent to revoke the breakthrough designation status of grazoprevir and elbasvir (MK-5172, MK-8742; Merck) due to other recently approved treatments for HCV genotype 1 patients.

Merck spokesperson Sarra S. Herzog confirmed via email that Merck was notified of the FDA’s request to rescind the designation, but noted that the FDA has not done so yet.

“The U.S. FDA informed us of their intention to rescind our breakthrough designation for grazoprevir/elbasvir for the treatment of genotype 1 HCV infection,” Herzog told Healio.com/Hepatology. “Note that they have not yet rescinded [breakthrough therapy designation].”

Herzog added: “Consistent with established FDA policies and procedures that govern the breakthrough therapy designation program, the FDA has indicated its determination is based on the availability of newly registered drugs that address this medical need. The company expects to discuss this matter with the FDA and does not expect that it will impact its ability to file [a new drug application] for this combination regimen or the timing of that filing.”

Merck still plans on filing a new drug application with the FDA in the upcoming months for the treatment regimen, according to the financial report.

Herzog also stated that Merck will be meeting with the FDA within the next few weeks to speak about the matter.

“During this meeting, Merck will have the opportunity to provide additional information which will help the agency determine the criteria for [breakthrough therapy designation] to continue to be met,” Herzog said.

Stephanie Yao from the Office of Media Affairs for the FDA declined to comment on the matter saying the FDA is unable to do so due to “federal law and FDA regulations [prohibiting] the agency from discussing products undergoing development.”

At the 2014 Liver Meeting in Boston, phase 2 study results were presented that indicated the treatment regimen was safe and well tolerated among treatment-naive patients with HCV genotype 1 and cirrhosis and patients previously treated with pegylated interferon and ribavirin, with or without cirrhosis, after 12 or 18 weeks of therapy.

Merck first received breakthrough therapy designation for the combination regimen in October 2013, according to Herzog. – by Melinda Stevens