Merck Gets Breakthrough Designation for Hepatitis C Drugs

Merck & Co. said Wednesday that its hepatitis C drugs have been designated breakthrough therapies by the U.S. Food and Drug Administration.

The news comes three months after the agency said it would rescind breakthrough designation due to the introduction of competing treatments for the liver disease. The drugs, grazoprevir and elbasvir, cured at least 90% of infected patients in a mid-stage clinical trials and Merck is testing them in late-stage studies. It hopes to file an application to market a new two-drug, single-pill combination.

In 2013, the FDA had granted grazoprevir and elbasvir breakthrough status for their use on patients with hepatitis C genotype 1. The new breakthrough designation also includes hepatitis C patients with genotype 4.

The FDA designates certain experimental medicines as breakthroughs if early tests indicate they would be a substantial improvement over existing options for serious diseases. It tries to speed the development and review of breakthrough drugs by working closely with the manufacturer and has approved several ahead of schedule.

As patent expirations weigh on drug makers, Kenilworth, N.J.-based Merck has been overhauling its research-and-development engine in hopes of introducing new treatments at least several months earlier than expected.

In hepatitis C, Merck is trying to catch up to market leader Gilead Sciences Inc., which analysts estimate raked in at least $12 billion in combined sales in 2014 from the blockbuster drug Sovaldi and the first all-oral combination drug, Harvoni. AbbVie Inc. recently introduced the second all-oral regimen, Viekira Pak.

In the hepatitis C market, especially, companies are engaging in price wars and giving deep discounts to consumers.

Merck shares edged up about 1% in premarket trading.

Write to Angela Chen at [e-mail]

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