Battle Against Counterfeit Drugs Has New Weapon: Pollen
After the Chinese company Guilin Pharmaceutical began getting complaints about its antimalarial medicine, artesunate, the company decided in 2006 to test some field samples. They turned out to be fake.
'They contained starch,' Ni Shizheng, vice president of Guilin Pharmaceutical, said in a recent interview. 'Our company didn't have the means to deal with the problem.'
But help was on the way. An unusual coalition of scientists, public health workers and police investigators used an innovative form of pollen analysis to help track down the source of those counterfeits, leading to the arrest of an organized crime ring that funneled the fake drugs from China into Southeast Asian countries, researchers wrote in a paper published Tuesday.
The investigation offers a new model for attacking what has become a flood of fake or subtherapeutic antimalarial drugs, which threaten to undermine the global fight against malaria, according to the study. More than one million people are believed to die each year from the disease.
The fact that the fake drugs contained wrong active ingredients and were traced to an illegal factory on the outskirts of Puning, a city in Guangdong Province, underscores international concerns about unlicensed chemical companies in China that export pharmaceutical products, some of them lethal. A factory in the Yangtze Delta sold counterfeit glycerin that ended up in cold medicine, killing nearly 120 people in Panama in 2006 and 2007.
Late last month, Vice Premier Wu Yi and the nation's top drug regulator, Shao Mingli, said separately that to improve drug safety the government intended to crack down on chemical companies illegally producing drugs.
Records from the Chinese drug-regulatory agency show that only three companies in China are certified to produce artesunate, yet The New York Times found dozens advertising the drug in bulk form on business-to-business trade portals.
Artesunate, developed by the Chinese and derived from a plant called sweet wormwood, is part of a combination therapy that has recently become a cornerstone of the fight against malaria.
'Those who make fake antimalarials have killed with impunity,' said an author of the new study, Dr. Paul N. Newton, of the Oxford University Center for Tropical Medicine in Laos.
The investigation was coordinated by Interpol, the World Health Organization and the Wellcome Trust, a medical research charity based in Britain. The study appears in the open-access journal PloS Medicine.
Using forensic palynology - analysis of pollen - investigators traced some of the fake drugs to southern China, close to the border with Vietnam, Laos and Myanmar, formerly Burma.
'All fake artesunate tablets contained charcoal fragments, presumably from vehicle exhausts and fires,' the study said. 'In some samples, charcoal was so abundant that it suggested the source was an area suffering severe air pollution.'
But it was certain types of pollen and calcite, a mineral mined in the Guangxi Zhuang Autonomous region in southern China, that led scientists to believe that the manufacturer was in southern China.
Armed with this information, Chinese authorities arrested Xu Qiang, a middleman or trader, in Yunnan Province. Mr. Xu used to sell legitimate pharmaceuticals, but was approached by Burmese traders who wanted fake drugs, said Wang Zhiguang, who works on intellectual property issues in the Ministry of Public Security of China. 'They wanted counterfeits because they were cheap and they could earn better profits,' Mr. Wang said.
In addition to Mr. Xu, two other Chinese residents were arrested with two citizens of Myanmar. But the manufacturer is still a fugitive and is also wanted for making counterfeit drugs in Shandong Province, Mr. Wang said.
Previous studies have estimated that between a third and a half of the artesunate tablets in mainland Southeast Asia are counterfeit. Mr. Ni, the Guilin Pharmaceutical official, said he believed that there were fewer counterfeit malaria drugs in Southeast Asia since the arrests. But he added, 'I can't say there are no counterfeits there now.'
Mr. Ni said many small, uncertified chemical plants sold artesunate as a raw material. 'Our company doesn't have any way to deal with this problem,' he said. 'Our company can't influence national policy.'
According to the study, some counterfeit artesunate contained subtherapeutic quantities, which could fool simple screening tests. These pills are particularly dangerous, the authors said, because in sufficient quantities they could lead to an artesunate-resistant form of malaria, 'which would be disastrous for malaria control in Asia and thereafter in Africa.'
Interpol provided a crucial bridge between the health sector and national police agencies in this case, the researchers said.
Walt Bogdanich reported from New York, and Jake Hooker from Beijing. Andrew W. Lehren contributed reporting.
This article has been revised to reflect the following correction:
Correction: February 15, 2008
An article on Tuesday about efforts to find the source of fake ingredients in Chinese antimalarial medicine misstated the official name of the geographic area of southern China where Guilin Pharmaceutical, a company that discovered the fakes in 2006, is based. It is the Guangxi Zhuang Autonomous region; there is no Guangxi 'Province.'