Wormwood: Artemisia annua fight vs malaria

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Tuesday December 12, 2:07 AM

Fakes, bottlenecks hobble herb's fight vs malaria

(This story is part of a package on malaria being issued on Dec. 11 ahead of a White House summit)

By Tan Ee Lyn



HONG KONG, Dec 11 (Reuters) - Li Guoqiao was a village doctor in China's southwestern Yunnan province in 1974 when the government asked him to try using an herbal drug, artemisinin, to treat malaria patients.

What followed was one of China's first clinical trials using the herb, and the results were startling. All 18 patients felt better within hours and recovered a few days later.

"Within 2 hours, their fever came under control. One of them was a woman who had just suffered a miscarriage and was unconscious when she was brought in. She recovered," said Li, now a professor at the Tropical Medicine Institute in Guangzhou University of Traditional Chinese Medicine in southern China.

Chinese herbalists used leaves from the Artemisia annua, or sweet Wormwood shrub, to treat mosquito-borne malaria for more than 1,500 years. But it was not until the late 1960s, that scientists identified the anti-malarial ingredient in the plant.

Today, artemisinin is widely regarded by medical experts as the best drug against malaria -- which kills a person every 30 seconds. According to the World Health Organisation (WHO), 90 percent of these deaths occur in sub-Saharan Africa.

In 2001, the WHO said artemisinin should be used in combination with other drugs to slow down any development of resistance.

But artemisinin is in short supply and this fact, plus the high prices charged for it, have led to the production of fake drugs, in some cases causing death.

"Fake drugs are all over the place and they are really creating problems in Asia. We are afraid they might get into Africa too as demand increases," said Kevin Palmer, WHO's regional adviser for malaria in the Western Pacific.

Fakes seized in recent years in Vietnam, Cambodia and Thailand contained no artemisinin.

"They are easy to fake, 97 percent of fakes seized are just chalk. It's very worrying ... someone is making millions," Palmer said, adding that Interpol was investigating the cases.

Professor Li said: "These people are very sick and after eating these pills, they are ineffective and the victims become unconscious and die. This is very unethical."

In Thailand, government workers conduct spot tests at least twice a year in districts where fake anti-malarial drugs are known to have surfaced. These districts are typically along the Thai-Cambodia and Thai-Myanmar border.

"We use our equipment, called mini-lab, to check the drugs in the field to see if they are genuine," said Wichai Satimai of Thailand's Public Health Ministry.

While there are no official figures of deaths from fake anti-malarial drugs in Thailand, Wichai said results were grave.

"Fake drugs cause complications and higher mortality. If the drug is sub-standard -- say it has only 50 percent of the active ingredient -- it can't kill the whole protozoa (parasite). It will produce drug resistance," Wichai told Reuters.

FAKES AND BOTTLENECKS

Malaria is one of the world's oldest diseases and infects between 300 million and 500 million people each year, killing over a million of them, according to WHO. It is also an economy killer, with the drain on African output estimated by WHO at $12 billion yearly.

It is caused by protozoan parasites, which thrive in humans and are passed person-to-person by female Anopheles mosquitoes.

There is no vaccine against the parasite, which has grown resistant to well-known anti-malarial drugs, like chloroquine and pyrimethamine.

In early December, the World Health Organisation launched a new global effort to find a vaccine by 2015. In the meantime, artemisinin-based combination therapies (ACTs) remain the most effective cure for the disease.

But supplies are tight.

"Supplies of the raw material (artemisinin) from China and Vietnam are limited. It's a natural product and they aren't growing enough to supply the world's demand," said Palmer.

Developing countries must buy ACTs from WHO-accredited suppliers if they want to use funds from the U.N.-backed Global Fund to Fight AIDS, Tuberculosis and Malaria. So far, only two suppliers -- Swiss drug maker Novartis AG and Guilin Pharmaceuticals Company in China's southwestern city of Guilin -- are WHO-accredited.

Launched in 2002, the Global Fund makes up about two-thirds of financing to prevent and treat malaria and it is the main financier of developing countries' scale-up of ACT drugs.

The Chinese drug maker will soon be switching production from artemisinin to ACTs. And that has increased fears of fakes.

"The people in Guilin are now worried that they (makers of fakes) will start copying their artesunate combination tablet, which they are producing for Africa. They are really scared," Palmer said.

One way to beat ACT fakes is to get more genuine suppliers accredited with WHO.

"The main producers of combination therapies are in China and Vietnam, but most of them don't meet international standards. They are not available for purchase by the Global Fund although they can be marketed as they are," said Palmer.

WHO is working with producers to improve their production facilities and quality control, he said.

"In many cases, these drugs are not getting to the people who need them, they are using less effective drugs because that's all they can afford," he said. "It's a real crisis at the moment."

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