Metagenics' Position on Recent Echinacea Trial

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Meta eNewsI thought some of you might enjoy seeing this view of the recent

research:

Ann

 

 

 

 

 

...BULLETIN August 2005

 

 

Exclusively for Healthcare Practitioners from Metagenics,

Inc.-Your Natural Health Sciences Resource

 

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Echinacea: One Study Does Not Tell the Whole Story

 

Metagenics' Position on Recent Echinacea Trial

 

Over the last two decades, numerous studies have

demonstrated the beneficial effects of echinacea preparations on immune system

function. Echinacea is commonly used to help prevent, shorten the duration of,

and relieve symptoms of upper respiratory tract infections associated with cold

and flu viruses. Research suggests it may activate phagocytic function, relieve

symptoms when used at the first sign of a viral infection, and reduce the

recurrence of infectious symptoms. In addition, it has been shown to be well

tolerated.

 

The recently reported and much commented on study

published in last week's edition of the New England Journal of Medicine has cast

doubt on the benefits of echinacea supplementation. Metagenics shares the

position taken by the American Botanical Council, which in summary states, " This

is not a definitive trial on the efficacy of echinacea, nor should the results

be generalized to echinacea preparations widely available. Unfortunately, the

conclusion that may be drawn by some media who report this study may state that

'echinacea is ineffective,' but this would be an incorrect conclusion based on

the design of this study and the evidence in the existing literature. "

 

(American Botanical Council. Herbal Science Group Says

Dosage Too Low in New Echinacea Trial. Available at:

http://www.herbalgram.org/default.asp?c=echinacea072605. Accessed August 2,

2005.)

 

Below you will find the response from the American

Botanical Council reprinted in its entirety. If you would like more information,

links are provided to the American Botanical Council, a trusted resource for

healthcare professionals and consumers alike.

 

 

Herbal Science Group Says Dosage Too Low in New Echinacea

Trial

 

(Austin, TX, July 27, 2005). The nonprofit American Botanical

Council (ABC), an Austin, Texas-based research and education organization, has

reviewed a new clinical trial on the popular herb echinacea for use in a

specific kind of induced virus, being published Thursday in the New England

Journal of Medicine.1 The study concluded that the echinacea preparations did

not prevent or help treat symptoms of a specific virus applied to the test

subjects. ABC has found several aspects of the design of the study worthy of

clarification, and comments on the potential misinterpretations of the

significance of this study.

 

First, the extracts used were made in a university laboratory

and do not correlate with commercial echinacea products currently available to

consumers. Second, the dosages used in this trial were probably too low. The

echinacea preparations used in the study might have shown activity at more

frequent dosing intervals and/or higher dosage levels-as is often the case with

contemporary echinacea use.

 

The new trial utilized extracts made from the roots of a

species of echinacea called Echinacea angustifolia. The randomized,

double-blind, placebo-controlled, seven-arm trial was conducted on 437 college

students who had a particular type of rhinovirus inserted into their nostrils

(the results were calculated on 399 subjects). In the trial, the echinacea

preparations were tested to see if they had a preventive effect or if they could

help treat the symptoms caused by the rhinovirus. The students who received the

three different echinacea preparations and were sequestered in a hotel room did

not experience fewer infections, fewer symptoms, or a reduction in the duration

of symptoms, compared with those who received the placebo.

 

The trial utilized three doses of 1.5 milliliters each of the

three laboratory-produced echinacea extracts, presumably equivalent to about 300

milligrams of the dried powdered root in each dose (equivalent to 900 mg per day

of the dried root). This level was chosen for the trial because it is the dose

recommended by the German government's expert herb panel called the Commission

E, which had conducted reviews of the research published on various types of

echinacea in the scientific and medical literature in the early 1990s.2

 

According to ABC various international monographs have

acknowledged the generally higher dose used for echinacea root products. The

World Health Organization (WHO) monograph for Echinacea root ( " Radix

Echinaceae " ) has a dosage for Echinacea angustifolia root at the equivalence of

3 gm per day of the dried root.3 This same dosage is also acknowledged in the

more recently developed draft monographs on Echinacea from the Canadian Natural

Health Products Directorate.4

 

This dosage level is about 330% higher than the dosage of the

echinacea preparations given in the NEJM trial. This supports ABC's contention

that the preparations may have been under-dosed and that the trial might have

shown a potentially positive trend if a higher dosage and/or increased frequency

of administration had been followed.

 

" It would have been optimal if this trial had tested the

echinacea preparations at more frequent and/or higher doses, " said Mark

Blumenthal, Founder and Executive Director of ABC. " Dosage is one of the most

important aspects in assessing any therapeutic agent. Many clinicians who

recommend echinacea for treatment of upper respiratory tract infections related

to colds and flu normally utilize a frequency of use and/or a total daily dose

that is higher than the one used in this trial. This is also true for consumer

self-medication with many commercial echinacea preparations according to some

label dosage suggestions. "

 

Blumenthal added, " The researchers have previous experience in

researching echinacea and have done an admirable job in testing a species of

echinacea (i.e., E. angustifolia) that has not been adequately researched. " But

he hastened to add, " The most accurate statement that can be said about this

trial is this: These specific laboratory-produced echinacea extracts, at the

dose given in the trial, under the specific design of this trial, did not

produce any measurable effect. " He emphasized, " This is not a definitive trial

on the efficacy of echinacea, nor should the results be generalized to echinacea

preparations widely available. Unfortunately, the conclusion that may be drawn

by some media who report this study may state that 'echinacea is ineffective,'

but this would be an incorrect conclusion based on the design of this study and

the evidence in the existing literature. "

 

" Dosing people for rhinovirus in a hotel does not necessarily

mimic real life, " said Bruce Barrett, MD, PhD, an Assistant Professor of Family

Medicine University of Wisconsin School of Medicine and an author of several

previous critical reviews on echinacea clinical trials. He noted that the

patients were possibly relatively resistant to the echinacea treatment. " College

kids are immunocompetent, " he stated, referring to the relative health of the

test subjects in the trial. " It may have been better to test older people to see

how they might have faired. "

 

However, Dr. Barrett was generally complimentary about the

trial in general. " This is a very valuable study and quite helpful, although it

has some significant limitations, including product, sample, and population, " he

stated. " In general, you may want to have about 100 people per treatment group

for more statistical significance rather than only about 50 per group used in

this trial. "

 

In general, products marketed as " Echinacea " are extremely

popular in the United States. Echinacea ranked second in sales in mainstream

market retail stores in 2004, according to an article in ABC's journal

HerbalGram.5 Total sales of echinacea products in all channels of trade in the

United States in 2004 was estimated at about $155 million, according to data

compiled by Nutrition Business Journal.

 

Blumenthal also added that although it was formerly quite

popular, there has been a trend away from using Echinacea angustifolia root in

commercial herbal products based on increased concerns by many responsible

members of the herb community regarding conservation and sustainability of wild

medicinal plants. Echinacea angustifolia is generally more difficult to

cultivate commercially than the other two more popular species of echinacea (E.

pallida and E. purpurea), and so more material from these species are found in

products on the North American market.

 

Blumenthal points to a body of clinical evidence that supports

the use of various echinacea preparations for treating symptoms associated with

colds and flus. A therapeutic monograph on Echinacea is available in The ABC

Clinical Guide to Herbs, ABC's reference book and continuing medical education

module.6 The monograph summarizes 21 clinical trials on various echinacea

preparations for colds, flus, upper respiratory tract infections, and other

uses. ABC has posted the complete echinacea chapter including this monograph on

its website as an educational service to the public.

 

The study has generated significant media attention. ABC and

Blumenthal have been contacted by a variety of news sources, including: the

Associated Press, Bloomberg Business News, CNN, the Los Angeles Times, NBC

Nightly News with Brian Williams, the New York Times and USA Today.

 

About the American Botanical Council

 

The American Botanical Council is the nation's leading

nonprofit organization addressing research and educational issues regarding

herbs and medicinal plants. The 17-year-old organization occupies a 2.5 acre

site in Austin, Texas, where it publishes HerbalGram, a peer-reviewed journal.

ABC is also the publisher of The ABC Clinical Guide to Herbs, a continuing

education and reference book, which contains extensive monographs on the safety

and efficacy of 29 popular herbs, including echinacea.6 More information on

echinacea is available on ABC's extensive website, http://www.herbalgram.org/.

 

References

 

1.. Turner RB, Bauer R, Woelkart K, Hulsey TC, Gangemi DJ.

An evaluation of Echinacea angustifolia preparations in experimental rhinovirus

infections. N Engl J Med 2005;353:341-348.

2.. Blumenthal M, Busse WR, Goldberg A, Hall T, Riggins CW,

Rister RS, eds. Klein S, Rister RS, trans. The Complete German Commission E

Monographs-Therapeutic Guide to Herbal Medicines. Boston: Integrative Medicine

Communications; Austin, TX : American Botanical Council, 1998.

3.. Echinacea Radix. In: WHO monographs on selected

medicinal plants. Geneva: World Health Organization, 1999.

4.. Echinacea. Natural Health Products Directorate. Health

Canada. Draft Jan 2004. Available at:

http://www.hc-sc.gc.ca/hpfb-dgpsa/nhpd-dpsn/mono_echinacea_e.pdf Accessed, Jul

27, 2005.

5.. Blumenthal M. Herb sales down 7.4 percent in mainstream

market. HerbalGram 2005;66:63.

6.. Echinacea. In: Blumenthal M, Hall T, Goldberg A, Kunz T,

Dinda K, Brinckmann J, et al, eds. The ABC Clinical Guide to Herbs. Austin, TX :

American Botanical Council, 2003.

For more information on echinacea, please contact Metagenics

Technical Support at 800.692.9400 or visit our Web site at www.metagenics.com.

 

 

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The information provided herein is a review of some of the

scientific literature on the topics discussed. The information contained herein

is intended for use solely by healthcare practitioners. Healthcare practitioners

are encouraged to conduct their own independent review of the applicable

scientific literature and make their own assessments.

 

 

 

 

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