With Merck & Co. poised to disrupt competitors with new hepatitis C drugs, rivals are scrambling to get ahead the best way they can figure: make a medicine that works faster.
It’s high stakes for companies like Gilead Sciences Inc., which earned more than $12 billion in sales last year from Sovaldi and Harvoni, market-leading medicines for the liver disease. Gilead, along with Achillion Pharmaceuticals Inc. and others, are trying to get treatment time down to six weeks or less, from 12 weeks or more offered by current drugs. Experts say it won’t be easy.
The greatest challenge is to design one drug that works more quickly for people with varying degrees of the disease, or who are also suffering from separate maladies.
“Hepatitis C has a complicated patient population,” Stefan Zeuzem, a liver disease specialist in Frankfurt who consults for drugmakers developing hepatitis treatments, said in an interview at a liver disease conference in Vienna. “The more advanced the disease, the longer the treatment required.”
While new combination drugs from Gilead and Achillion have shown high cure rates after six weeks of therapy, those results were for patients who are the easiest to treat.
“The failure rate was unexpectedly high” in Gilead’s study among those who had taken other medicines and relapsed, Edward Gane, lead investigator for both the Gilead and Achillion studies, said in an interview. The Gilead trial, presented last week, also showed that patients with cirrhosis, one of the major complications of hepatitis, had a lower cure rate than those with less severe forms of the disease.
Companies will have to demonstrate that the drugs have a sustained effect in those tougher patient groups at the quicker pace to win over regulators, including the U.S. Food and Drug Administration, said Paul Pockros, a hepatologist at the Scripps Clinic in La Jolla, California.
“The FDA really doesn’t want to accept any relapse at all,” he said.
Achillion plans to study its drugs in broader patient groups, including those with advanced fibrosis, said Glenn Schulman, a spokesman for the New Haven, Connecticut-based company.
“Next-generation regimens, including ours, will have to simplify and shorten treatment duration across broad patient populations,” he said.
Gilead representatives weren’t immediately available to comment.
Merck, the second-largest U.S. drugmaker, is poised to enter the market next year with a combination of two drugs that cured 95 percent of previously untreated hepatitis C patients in a late-stage study. Trial results show it may be effective in a wide range of patients. But it still took 12 weeks.
New drugs will be more appealing if they have a single treatment length for all patients and don’t add complexity to guidelines that are already 39 pages long, said Zeuzem, who is also a professor of medicine at Johann Wolfgang Goethe University Hospital. The treatment guide comes from the European Association for the Study of the Liver.
The hepatitis C virus has 11 genotypes, while some patients have cirrhosis, a condition in which scar tissue develops in the liver, and some have the HIV virus. Other factors including baseline viral load -- the amount of virus present -- can also affect the length of cure, Achillion’s Schulman said.
While AbbVie Inc. and Gilead have drugs approved for genotype 1, Bristol-Myers Squibb Co. is seeking clearance to use a medicine in genotype 3. An AbbVie medicine called Viekira Pak is also showing promise in curing people who suffer from both hepatitis C and severe kidney disease.
All are advances, but the top goal is to find one treatment that works for most patients in a single amount of time.
“If you can treat that very difficult population, then by default you should be able to treat the easier-to-cure patient with that same regimen,” said Fred Poordad, a hepatologist and vice president for academic and clinical affairs at the Texas Liver Institute in San Antonio. “It’s not a bad strategy to start with the most difficult groups.”