Herbal relief for hepatitis
sufferers?
Berkeley researchers, reviewing clinical trials, find extracts from
plants, roots, even toad skins potentially effective against this
chronic disease
http://www.berkeley.edu/
By Sarah Yang,
Public Affairs
02
October 2002
| Chinese herbal
treatments, combined with standard therapy, may be more effective than
standard therapy alone for treatment of chronic hepatitis B, according
to an analysis of randomized, controlled trials led by Berkeley
researchers.
Researchers analyzed 27 clinical trials in which chronic hepatitis B
patients using Chinese herbal medicine alone, or in combination with the
protein interferon alfa (the standard treatment for the infection), were
compared with a control group of patients who were taking only
interferon alfa. The meta-analysis, published this week in the American
Journal of Public Health, found that the most encouraging results came
from patients who used a combination of Chinese herbal treatments with
interferon alfa.
“The results
are encouraging enough that, if I had chronic hepatitis B and had
previously failed interferon alfa treatment, I would talk to my doctor
about combining interferon alfa with Chinese herbal medicine,” says
Michael McCul-loch, a doctoral student in epidemiology at UC Berkeley’s
School of Public Health and lead author of the study.
According to
the World Health Organization, 2 billion people worldwide are infected
with hepatitis B, 350 million of whom have the chronic form of the
disease. About three-fourths of those with chronic hepatitis B, which
increases the risk for primary liver cancer, live in Asia. Primary liver
cancer is the fourth-leading cause of cancer death worldwide.
“There is a
wealth of data about hepatitis B from researchers in Asia because the
disease is endemic in that part of the world, but accessing that
information has been — and still is — difficult because few of those
studies are published in English-language journals,” says McCulloch, who
is also a research fellow at the Chinese Academy of Sciences in Beijing.
McCulloch, a
licensed acu-puncturist who earned his bachelor’s degree in Chinese
studies at Berkeley, searched through six databases of medical
literature, including clinical-trials data published in Chinese-language
journals.
The ingredients in the herbal treatments included mixtures of plant and
root extracts, and they varied from study to study. Two of the 27
studies specifically looked at bufotoxin, an extract from the skin of
the toad Bufo gargarizans. Another two studied kurorinone, an extract
from the root of the plant Sophorae flavescentis.
The authors
included only trials in which patients using Chinese herbal medicine
either alone or with interferon alfa were compared with a control group
using only interferon alfa at least three times per week. The studies
must also have included data on at least one of three markers of
infection: levels of hepatitis B surface antigen (HBsAg), hepatitis B e
antigen (HBeAg) and hepatitis B virus (HBV) DNA. All three measures
indicate an active infection.
Overall,
Chinese herbal medicine combined with interferon alfa was 1.5 to 2 times
as effective as interferon alfa alone in reducing the hepatitis B viral
load to undetectable levels for all three measures of infection. In
particular, bufotoxin combined with interferon alfa was significantly
more effective than interferon alfa alone in measures of HBeAg and HBV
DNA, but not for measures of the surface antigen. Kurorinone was nearly
as effective as interferon alfa in the two studies that tested it.
For measures of
the surface antigen, patients receiving herbal treatment alone performed
twice as well as those receiving only interferon alfa. The results did
not differ significantly between the two groups for measures of HBeAg or
HBV DNA.
“Bufotoxin and
kurorinone have been singled out as having the best potential for being
investigated for drugs,” says McCulloch, who is also a research fellow
at the Chinese Academy of Sciences in Beijing. “However, it may be that
the key to the way these herbal therapies work is by acting together as
a group. That’s one of the great challenges in studying herbal
treatments, yet it is one of the most fascinating aspects of Chinese
medicines. These particular mixtures are a distillation of centuries of
clinical use.”
The
investigators also showed that the quality of the studies left much room
for improvement. Many of the studies had incomplete information on how
patients were randomized, and “blinding” of patients and doctors to the
type of treatment administered did not occur in most of the studies.
“We cannot make firm conclusions about the use of Chinese herbal
medicines based upon the results from these clinical trials,” says Dr.
Jack Colford, associate professor of epidemiology at UC Berkeley’s
School of Public Health and senior researcher for the study. “But the
findings revealed by this analysis certainly justify additional
investigation of these herbal therapies in more rigorous trials.”
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