24 MAY 2007
In a groundbreaking announcement Monday, researchers revealed that a one-two drug treatment can cure many hepatitis C patients. The virus hepatitis C is a major cause of cirrhosis, liver cancer, and deadly liver failure, and 3.2 million Americans carry it.
"Cure" is a word that doctors are loathe to use, but it is appropriate in this case, said Mitchell Shiffman, professor in the Virginia Commonwealth University School of Medicine, and chief of hepatology and medical director of the liver transplant program. "It is rare in the treatment of life-threatening viral diseases that we can tell patients they may be cured. In hepatitis C today, we are able to help some patients achieve an outcome that effectively enables them to put their disease behind them."
Shiffman was one author of the new study, which is a long-term follow-up of hepatitis C patients who had already benefited from combination treatment with two medicines:
Pegylated interferon alfa-2a, a long-acting type of interferon that
we'll call peginterferon. Interferon is a natural compound that the immune system uses in its battle against viruses.
Ribavirin,
which prevents some viruses from hitting the "copy" button.
Although many viral diseases, including smallpox, influenza, and other types of hepatitis, can be prevented with vaccines, medicine seldom talks about cures once a virus has gotten established, Shiffman said. "This a very, very important piece of data. It shows what many hepatitis C doctors have believed for a long time, that we do cure hepatitis C, and it shows that pretty conclusively."
A welcome confirmation
The new data was reported by Shiffman's colleague Mark Swain, of the University of Calgary (Canada), to the Digestive Diseases Week, an all-digestion, all-the-time scientific jamboree supported by several digestion-digging medical associations. The study followed 996 patients who had previously been treated with peginterferon, in most cases combined with ribavirin. All these patients had a "sustained viral response," meaning the virus could not be detected in their blood six months after treatment.
Amazingly, when patients were followed for an average of 4.1 years after treatment ended, the virus could be detected in less than 1 percent of these patients. To Shiffman, that justifies using the word "cure." After a long-term follow-up, "More than 99 percent remained virus-undetectable. That is a cure for hepatitis C."
People who injected drugs face the highest risk of hep
C infection. Because the virus is carried on blood, sharing needles efficinently
spreads the virus, and 60 percent to 80 percent of people who shot drugs for
at least 5 years are infected. Infection rates in prison range from 15 percent
to 40 percent. More than 80 percent of the nation's estimated 1.7 million current
injection drug users have spent time "inside." Data
from the CDC.
Hepatitis C infection rates in the 1980s reached 240,000 new cases per year. Although that annual rate has fallen to 26,000, an estimated 3.2 million Americans carry the virus, which puts them at risk of cirrhosis, liver cancer, and liver failure. Many patients will die of these diseases unless they can get a liver transplant. Hepatitis C is spread by infected blood, mainly through needle sharing by drug users.
Interferon works directly, by reducing the virus's ability to reproduce, and indirectly, by stimulating the immune system to attack the virus. Despite considerable early hoopla, interferon was not very effective against hepatitis until the 1990s, because it broke down too quickly in the body. Pegylating the interferon, a process introduced in the 1990s, slows that degradation, allowing interferon to do its job.
The second component of the treatment, ribavirin, interferes with the virus's
ability to reproduce, says Shiffman. "It is critically important in preventing relapse. 
Interferon gets rid of the virus, and ribavirin prevents it from coming back after the treatment is over." The drugs are administered simultaneously; interferon by injection, and ribavirin as a pill.
Chronic hepatitis C infection can cause cirrhosis of the liver, which degrade's the liver's ability to detoxify compounds in the body. In developed countries, liver diseases caused by hep C are the leading cause of liver transplants. Photo: JHU, Division of Infectious Diseases
The fine print
The good news was amplified by the fact that even hard-to-treat groups, like those with cirrhosis or HIV infection, fared equally well once they had cleared the virus during initial treatment.
But there are some reservations:
Drinking
too much alcohol isn't the only way to wreck your liver. Hepatitis C
can do the job much quicker...
Despite these cavils, Sosman finds the new finding credible, since it confirms the effectiveness of what has been the standard treatment for almost a decade: peginterferon plus ribavirin. "Our assumption is probably right. Those folks who are able to maintain a sustained viral response at 6 months are probably cured."
"We can tell patients, if you are on treatment, and respond to the drug and remain virus negative, if it does not come back in the first few months, you are cured," says Shiffman. "We have not been able to say that for sure. Although I have believed that for a long time, it is very nice to see that in such a large patient population. Hepatitis C is now something we can cure."
-- David J. Tenenbaum
Related Why Files
• Tattoos.
• Corn beer.
• Plant vaccines.
Bibliography
• Study Cites Safety Questions About Diabetes Drug, Stephanie Saul, The New York Times, May 22, 2007.
