Counterfeit Malaria Drugs Seized in China
A one of its kind collaborative study between scientists, health workers and police has led to the arrest of alleged traders of fake anti-malarial drugs in China. The investigation highlights the growing threat posed by fake pharmaceuticals and the difficulties of tracking down those responsible for their manufacture.
The investigation, known as “Operation Jupiter,” included INTERPOL, the World Health Organization’s Western Pacific Regional Office, and the Wellcome Trust-University of Oxford SE Asian Tropical Medicine Research Program, in close cooperation with Chinese authorities. Scientists from five other laboratories analyzed the composition of 391 samples of genuine and fake artesunate tablets collected across SE Asia, and also studied their packaging.
The Chinese authorities reported they had seized hundreds of thousands of tablets of a counterfeit version of the drug artesunate, and arrested a dealer in southern China. Police believe they have exposed a major Asian trade in the fake medicine.
Such problems have been particularly intense in Southeast Asia since 1998, and the investigation revealed as many as half of the malaria tablets sampled in Vietnam, Cambodia, Laos, Myanmar and along the Thai/Myanmar border were counterfeit versions, disguised with authentic-looking packaging including fake holograms.
Artesunate is an important part of the Artemisinin-based combination therapy recommended by the World Health Organization (WHO) since 2001 for the treatment of malaria.
Most of the counterfeit drugs contained no artesunate. Instead, some contained a wide range of potentially toxic ingredients, including prohibited pharmaceuticals such as metamizole, and raw materials, such as safrole, used for the manufacture of the drug ecstacy. However, some tablets contained small amounts of artesunate, possibly to foil screening tests. Although these doses were too low to be effective, they were high enough to contribute to the development of resistance in malaria parasites, making it even more difficult to fight the mosquito-borne disease that still claims over a million lives per year.
“Artesunate, as part of artemisinin-based combination therapy, is vital for malaria treatment and is one of the most effective weapons we have against this terrible scourge. Those who make fake anti-malarials have killed with impunity, directly through the criminal production of a medicine lacking active ingredients and by encouraging drug resistance to spread. If malaria becomes resistant to artesunate, the effect on public health in the tropics will be catastrophic,” said Dr Paul Newton of the Wellcome Trust-University of Oxford SE Asian Tropical Medicine Research Program, the study’s lead author, in a press release.
In addition to analyzing the chemistry of the samples, researchers used a technique known as forensic palynology to study pollen contamination within the fake tablets with the aim of tracking down the likely location of manufacture. The pollen evidence suggested that at least some of the counterfeit artesunate came from southern China, and this was supported by examination of the mineral calcite, found in some of the samples.
Chinese authorities used these results to locate and arrest a suspect in China’s Yunnan Province in 2006. The man is alleged to have traded 240,000 blisterpacks of counterfeit artesunate, enough to “treat” almost a quarter of a million adults. While the Chinese authorities were able to seize 24,000 of these packs, the remainder are thought to have been sold at crossings on the border of Yunnan and Myanmar, accounting for almost a half of all blisterpacks of artesunate sold to the region.
Dr. Newton warned this may be just the tip of the iceberg when it comes to counterfeit medicines. “There are probably other similar problems with other life-saving medicines we are unaware of,” he said in a telephone interview with Reuters.
PHOTO CAPTION: Genuine Artesunate
On the Net:
A full report of the investigation is published in the Public Library of Science
journal PLoS Medicine. It can be viewed here.