Artemisinin and Malaria
Wednesday, January 07, 2009
I have received this comment from an anonymous poster after reading my post on The World Health Organisation Traditional Medicine Hoax and I thought it deserved a wider readership. I wish all anonymous comments were like this...
As one of the people who has been directly involved in the development of artemisinin based therapy for treating malaria, I just wanted to set the record straight on the use of herbal Artemisinin for treating malaria and its origins.
It was indeed known from old times that an aqueous extract, i.e. a tea, of a plant called Artemisia Annua, could be used for lowering fever. However, the extension of its use to the treatment of malaria has only taken place during the 1960’s after research performed in China.
At the time, a war was going on in Vietnam and one of the main problems for the Vietcong was not the US soldiers on the ground, but the lack of proper medication against malaria, as quinine or other products could not be shipped to them as they were under Western control. The Vietcong asked Mao to help them and several hundred Chinese researchers started investigating whether they could find an alternative. After a considerable search, they found that a petroleum ether extract, so not the aqueous extract, of the herb Artemisia Annua showed antimalarial activity. Further research showed that this action was due to one single compound, called artemisinin and this substance was subsequently extracted and purified.
Even so, the extracted artemisin itself has a very poor solubility and therefore bioavailability and it was further chemically modified to other derivatives like artesunate, artemether and arteether.
In the early 1990’s the existence of this product was revealed to the west at a WHO conference on malaria held in China. This was a major breakthrough, as the malaria parasite had developed resistance against most known Western drugs. Therefore, several pharmaceutical companies, Sanofi, Roche & Novartis then started the full clinical development of the product. The reason for going through the whole process of toxicological and clinical research was to be able to clearly define the safety and to find the proper dose and administration regime for the compounds.
In the early 1990’s some companies started marketing the product in Asia as a monotherapy of about 100 mg artesunate daily for a duration of 7 days. This treatment in itself is very effective, but as most people feel better quickly there are not many patients that take the pills for the full duration, so to shorten therapy length and to prevent resistance from building up, it was then decided by WHO, to state that artesunate and artemether are only to be used in combination with other drugs like lumefantrine, sulfadoxine or amodiaquine.
This lead to new toxicological and clinical research and finally around 1998, and a clinical program including up to 4 000 patients, the first combination therapy artemether-lumefantrine was launched by Novartis, this was later followed by other combinations like artesunate-sulfadoxine-pyrimethamine and artesunate-amodiaquine.
These fixed dose therapies, in which an artemisinin derivate is combined with another chemical western based drug molecule are nowadays the only recognized and formally approved artemisinin combination therapies (ACT) as endorsed by WHO for the treatment of malaria.
In conclusion, although the origin of ACT therapy certainly is to be found in Traditional Medicine, because off the chemical modifications and purifactions performed after extracting a single clearly defined substance from the herb, the combination with western synthetic drugs, and the clinical research programs that went into it before its acceptance by the WHO and other health authorities, I feel it would be hard pressed to use the current ACT treatment as an example of the effectivity of Traditional Medicine or herbal medicine.
I find this quite interesting. Artemisinin is one of the drugs that supporters of Chinese Medicine trot out to show that Chinese herbalism is full of untapped wisdom. Frankly, I think it is more like the exception that proves the rule, and this comment highlights what had to be done in order for it to become an effective, quantified and deliverable treatment.
My guess is that most herbal products of all traditions are more cultural in meaning than pharmaceutical. Homeopathy is a derivative of Western herbalism that grew out of the Doctrine of Signatures. This form of sympathetic magic stated that a disease could be cured by herbs that somehow resembled the illness. For example, an "arrow-shaped leaf might be a good treatment for arrow wounds. Plants with yellow sap would be jaundice treatments, and plants and animals with long lives could be used to extend human life.". Homeopathy extends this principle with its central concept of 'like-cures-like' and still continues in this tradition - e.g. shipwreck if you feel 'stuck' in your life.
Undoubtedly, other forms of herbalism are founded on similar culturally derived ideas. There maybe a few more gems hidden in traditional pharmacopeias, but this does not mean we should uncritically accept the claims of herbalists at face value.
Labels: Traditional Chinese Medicine
posted by Le Canard Noir at
9:48 PM
5 Comments:
"Do you know what they call alternative medicine that's been proven to work? Medicine!"
cracking comment from Anonymous!
Andy
Love the covert reference to Scary Mary and her shipwreck drivel. I see that her Helvetia proving site is still down. Maybe these quacks do have a sense of shame.
I agree with teekblog that anonymous did actually write a good post. I assume it is all correct and checks out medically.
I am not sure how valid it is to day that something is the result of 20,000 years worth of traditional medicinal usage when it seems to have been identified and isolated in a chemistry lab in the Vietnam War era.
I guess aspirin is another good example. It might start out as witch doctor juju delivered with devil dances, chants and incantations but then some chemist comes along and turns it into a medicine with standardised production, dosage etc.
These doctors eh ?
Firstly, the science about medicinal plants, which names "herbalism" doesn't exist. Herbalism is a branch of quackery.
Name of the science about medicinal plants is Pharmacognozy.
The difference between "herbalism" and "pharmacogonozy" is like the difference between "nutriceutics" and "Dietetics" or between "homeopathy" and "Pharmacology".
Pharmacognozy (sometimes as its partial synonym is used term "phyto-chemistry") is normal science, which based on scientific principles and hasn't any unproven and sham components in its system.
Its aims is standardization of plant drugs and individual compounds from plants, study of chemical composition and pharmacological effects of plant drugs, isolation and purification of chemical compounds from plants, etc.
So, all work, which is described by this anonymous, is standard work of any scientists from pharmacognostic laboratories.
Pharmacology, Pharmacogonzy, Dietetics, Surgery, Physiotherapy, and other same are normal sciences or branches of conventional Medicine.
And their antipodes - homeopathy, herbalism, nutriceutics, spiritual healing, chiropractics are forms of quackery.
Well, if some quackbusters don't know right name of real scientific specialties, it is not very surprising. Simply some quackbusters have not education in the field of natural sciences or medicine. However, I was shocked, when I saw that some British universities close Chairs of Pharmacology or Pharmacognozy (one day I saw that some University shut whole Dept of Chemistry!), but they open instead of it different quackery courses such as herbalism, chiropractics, homeopathy, and other shit. Why?!
I think that David Colquhoun is right, when he says that it happens because managers-bureaucrats try to rule universities. While HR-managers and IT-specialists, who illiterate in real natural sciences, try to run Universities and control real scientists and academics, we shall watch dominance of quackery courses in universities and presence of half-educated "doctors of CAM" in our hospitals. These "marvellous" herbalistic "doctors" are not capable even to explain, why treatment which was used by them, works. It is understandable - they used treatment, which was invented NOT by herbalism. And the letter of this anonymous scientist shows it.
Oh, nevertheless, what a succes all these herbalistic idiots has in HR and IT offices! They are favourite there.
Well...Endarkenment... Dead night.
who proves to be 'closed-minded' in this example...the herbalists who continue to use the crap which didn't work, or the Big Bad Pharma boffins, who did the science and came up with a valuable addition to the therapeutic arsenal. See, the Scientific Method does work.
Science 1 Superstitious losers 0
Artemisinin exemplifies two aspects of herbal use. First, it is not always present in artemisia; it is produced, or not, depending on the growing conditions. Therefore, using the herb as a remedy can fail simply because one happened to harvest the wrong, individual plant. This is a general problem for herbal preps: without knowledge of the active ingredient (if any) one can never be assured it is therapeutic. Most of the time when a compound is said to the active component in an herb, it is only a wild guess based on a chemical that is characteristic or abundant in a plant. The bottom line, quality control in most herbs is impossible.
Second, the screening program that identified artemisinin rejected more than 100 other herbs used in TCM for malaria. A 1% success rate in a search for a new drug is outstanding; but when one goes to an herbal therapist and there is only 1% chance it will be effective, that is not good.
@John H., It is a common misconception that aspirin is a natural product that was used historically. It is chemically related to salicin (in willow bark) and salicylic acid (meadowsweet); but the drug was first prepared in a lab. (Aspirin is a natural product (found, I don't know when, in Filipendula ulmaria); however, I don't think the quantity is sufficient for use as a drug.)
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