Clinical

HCV may respond to herbal concoction, including mistletoe, when interferon fails

Last Updated: 2004-05-19 16:46:29 -0400 (Reuters Health)

By Karla Gale

NEW ORLEANS (Reuters Health) - Treatment with a mix of herbs that includes extracts of mistletoe and green tomato may lead to a sustained response in patients with hepatitis C (HCV) for whom treatment with pegylated interferon-alpha has failed or is contraindicated, according to findings presented here at Digestive Disease Week.

This concoction is not recommended as first-line treatment, however, since conventional therapy has a higher success rate with a shorter duration of treatment. The possibility also exists that mistletoe itself may be dangerous for patients with severe liver disease.

Dr. Harald Matthes and colleagues included 85 patients in their sample, 7 of whom withdrew from the study. Treatment included subcutaneous injections of mistletoe extract (Viscum album), and oral extracts of green tomato (Solanum lycopersicum) and Hepatodoron (Fragaria vesca and Tritis vinifer).

After 12 months, 18% were complete responders, 49% were partial responders and 33% were nonresponders. After 1 more year of treatment and an additional 6 months' follow-up, the corresponding rates were 44%, 28% and 28%.

About 60% of patients exhibited local responses to the injection, but otherwise adverse events were mild and uncommon. The group estimates the cost to treat each patient who achieves a sustained response is $5,600 with the herbal extracts, compared with $28,000 for treatment with interferon.

In an interview with Reuters Health, Dr. Matthes, based at Charite University of Berlin in Germany, explained that the mistletoe extract activates CD4 T helper-1 cells to induce an HCV-specific immune response, and the Hepatodoron stimulates liver regeneration.

The green tomato contains alkaloids that induce apoptosis through the caspase 8 pathway. "This is important because HCV blocks hepatocyte apoptosis, which is required to clear infected cells from the liver," he said.

As a result, liver enzyme levels actually increase during the first 4 to 8 weeks of treatment, he added, but then drop to normal levels as liver inflammation and necrosis resolve.

He noted that mistletoe is used as an adjuvant to treat approximately 60% of oncology patients in Germany, so its safety profile is well established.

However, he would not recommend these agents as first line treatment, since interferon is associated with a better response rate and requires only one year of treatment.

Dr. Paul Pockros, from Scripps Clinic in La Jolla, California, told Reuters Health he was concerned that herbal treatment could induce hepatocyte apoptosis, "which could be quite dangerous for patients with an impaired hepatic reserve." He also thinks it should not be recommended until its mechanism of action is better understood.

However, he agrees with Dr. Matthes that such treatment could be appropriate for patients who have no other choice of treatment for HCV.

But that remains a moot point in the U.S., he added, because subcutaneous injections of mistletoe are considered a drug rather than a dietary supplement, and have not been approved by the FDA.

Digestive Disease Week is jointly sponsored by the American Association for the Study of Liver Diseases, the American Gastroenterological Association, the American Society for Gastrointestinal Endoscopy, and the Society for Surgery of the Alimentary Tract.