MORE MEDS: Two new drugs that are expected to be approved by the FDA this spring might improve outcomes for patients with a tough form of hepatitis C, but they won't simplify treatment. Image: iStockphoto/frenc
Some 3.2 million Americans have chronic hepatitis C, an infection that can linger in the body for years before producing symptoms. It can eventually lead to serious liver scarring and cancer. And most infections in the U.S. are the disease's particularly tough breed, known as genotype 1, which has a cure rate of less than 40 percent with the best current treatment.
Two new drugs for this type, however, are now racing toward approval by the U.S. Food and Drug Administration, which could come as soon as late May. Both compounds are protease inhibitors and are expected to hit the market at about the same time.
Hepatitis C is spread through contact with blood and occasionally other bodily fluids, and 65 to 70 percent of people infected with the disease are unaware that they have it, according to John Ward, director of the Division of Viral Hepatitis at the U.S. Centers for Disease Control and Prevention. In the U.S. about one in 30 baby boomers has hepatitis C, and one in four people with HIV has the infection, he noted at a 2010 talk. The disease is responsible for some $33.3 billion in medical costs each year.
"We've been waiting for these drugs for a long time," says Darryn Potosky, a hepatologist at the University of Maryland Medical Center, who often has to tell patients they face steep odds of beating the disease.
If the new drugs come to market, patients would take one or the other in addition to the current two-drug treatment regimen. "It seems hepatitis C therapy is moving in the direction of HIV therapy, with multiple drug cocktails," Potosky says. And with that come "hopes that we can tailor treatments to patients."
Two new studies of one of the drugs, boceprevir, will be published in the March 31 issue of the New England Journal of Medicine. Both phase III trials were funded by Schering-Plough (now part of Merck), which makes the drug. There have not yet been any studies comparing boceprevir and the other new protease inhibitor, telaprevir (made by Vertex), but given the drugs' similarity, experts say they both seem promising.
In the new boceprevir trials, adding the drug to the current standard treatment (of interferon and ribavirin) effectively doubled the percentage of patients who were able to suppress the virus—an effect called sustained viral response, which is a mark of being effectively "cured."
"Patients with hepatitis C genotype 1 infection can anticipate a significant therapeutic advance," says Donald Jensen, a professor of medicine at the University of Chicago Medical Center, who wrote an editorial on the new research for the same issue of NEJM. But because these new drugs will each need to be used in combination with the existing two-drug regimes, they "will be associated with more side effects and more complexity."
Long road to safety
Doctors have long hoped for a safe and effective drug to beat hepatitis C (HCV) genotype 1—which, among strains of the disease, is "the most common and the hardest to treat at the same time," Potosky says. Some 70 to 80 percent of people infected with hepatitis C in the U.S. have this type.
With excitement building for these new drugs to arrive in the market, those who have been working on the problem have not forgotten that getting to this point "has been painstakingly slow," says Stuart Gordon of Henry Ford Hospital in Detroit, who coauthored one of the new studies.
Just finding the right compounds was challenging, he notes. An early protease-inhibitor contender, made by Boehringer Ingelheim, was found to be too toxic, and "many of the HCV polymerase inhibitors had to stop their development because of unacceptable side effects," Gordon notes.
And because the new treatment regime must be shown to be better than the current standard of care, which is a 48-week course, "the sheer time involved in conducting these large trials" made for slow going. But a payoff might be near.