May 18, 2004 -- With current hepatitis C treatments, about half of all patients can now be cured -- that's great if you're in that half. Now, two novel therapies -- one conventional, one unconventional -- show promise for treating those people for whom standard medications fail.
"About one in four patients can't tolerate current hepatitis C drugs because of harsh side effects," says Harald Matthes, MD, medical director and chief of the department of gastroenterology at Havelhohe Hospital for Anthroposophically Extended Medicine in Berlin. "And there are other patients that just don't respond."
In one study, an experimental pill that prevents replication of the hepatitis C virus worked in more than 70% of patients for whom traditional measures failed.
In the other study, a novel agent made from compounds found in mistletoe and green tomatoes cured about half of patients who didn't respond to conventional therapy.
Both studies were presented here at Digestive Disease Week.
Most Unaware They Have Hepatitis C
About 4 million Americans are infected with hepatitis C -- most of whom don't know it, according to the National Institutes of Health. That's because hepatitis C often causes few symptoms. The virus can be transmitted from an infected person by sharing needles or from an infected mother to her baby during birth. Alternatively, many have had the virus for years, having contracted it from a blood transfusion or organ transplant before 1992, when supplies began to be screened for the disease.
Despite its silence, hepatitis C can be deadly. According to Eliot W. Godofsky, MD, hepatitis C will be responsible for up to 30,000 deaths a year over the next decade. Godofsky is president and co-founder of Bach and Godofsky, the largest private infectious disease practice specializing in the treatment of viral hepatitis in the U.S., and clinical assistant professor of medicine at the University of Southern Florida in Tampa.
"The good news is that despite popular misconceptions, hepatitis C is curable [for many patients]," he tells WebMD.
Standard treatment with the immune system-boosting drug interferon (known as Intron A, Pegasys, or Peg-Intron) and the antiviral drug ribavirin (known as Copegus and Rebetol; the combination drug is called Rebetron) achieves a "sustained response" in about 50% of people with the most common subtype of hepatitis C, he says. That means that the virus has been eliminated from their blood -- and doesn't return even after treatment is stopped.
Novel Drug Interferes With Viral Life Cycle
Enter the novel therapies. In an early study of 48 patients infected with HCV-1 (the most common form of the virus in the U.S.), virus levels dropped in 70% of those who were given the novel anti-viral drug dubbed NM283. In comparison, none of those given a placebo experienced a dip in the amount of virus present, Godofsky tells WebMD.
"Unlike current therapies, NM283 actually interferes with a specific step in the virus' life cycle, much like the drugs used to treat HIV or hepatitis B," he says. "That's dramatically different from available treatments, which work by boosting the immune system."
Also, there were no major side effects -- just some transient gastrointestinal ailments such as nausea or vomiting that subsided after two days, Godofsky says. In contrast, interferon can cause flu-like symptoms, fatigue, depression, muscle aches, and hair loss.
NM283 is made by Idenix Pharmaceuticals of Cambridge, Mass., which funded the study.
The next step, he says, is to test it in larger numbers of people, and then in combination with interferon. "Lab data shows that NM283 and interferon work better [together] than either by itself," Godofsky explains.
Anna Suk-Fong Lok, MD, professor of internal medicine at the University of Michigan Health Systems in Ann Arbor and a board director for the American Liver Foundation, says the drug looks promising.
Nevertheless, she tells WebMD, "Its true effectiveness can't be gauged until we have longer, larger studies. You have to give the drug for enough time to see if there is a sustained viral response, if the virus comes back, when you stop it."
Mistletoe-Green Tomato Combo Wipes Out Virus
In the other study, "unconventional therapy" with an extract of mistletoe and green tomatoes wiped out the virus in nearly half of patients for whom standard interferon therapy had failed, Matthes tells WebMD.
"We used a whole extract of mistletoe, which stimulates the immune system" to fight off the virus, he says. "And green tomatoes contain a key enzyme called caspase-8 that stimulates cell suicide."
In the study, 85 patients were given the new treatment. At one year, 18% were cured; by two years, the cure rate had reached 44%, Matthes reports.
"It's not quite as high a response rate as you see with interferon and ribavirin," he says. "But for the patients who can't tolerate that treatment and who currently have no alternative, we now have an option."
Godofsky says he sees a day when hepatitis C patients will be treated with a combination of therapies, much like people with HIV/AIDS. "We need combinations of different drugs that target different aspects of the disease. But drug development is a timely process."