Counterfeit drugs have become a major public health problem in many developing nations. But such deadly schemes can be foiled if public health officials, scientists, and the police join hands across borders, a paper in the current issue of PloS Medicine shows. The research led to the arrest of two people in China in 2006 and may have helped close one supply line of fake malaria drugs to Southeast Asia.
The group--under the auspices of the International Criminal Police Organization (INTERPOL) and the World Health Organization's (WHO's) regional office in Manila--investigated counterfeits of artesunate, a malaria drug produced by Guilin Pharmaceutical in China and sold widely in private pharmacies in Southeast Asia. Researchers bought or collected 391 samples of what was sold as Guilin's artesunate in Vietnam, Cambodia, Laos, Myanmar, and border areas of Thailand. Close inspection of the packaging revealed that many were counterfeit: In almost half of the samples, the small hologram Guilin uses to guarantee authenticity proved to be a fake. (Some were "terrible," says Paul Newton of Mahosot Hospital in Vientiane, Laos, the paper's first author; others were so convincing that even malaria experts could not tell them apart with the naked eye.)
Chemical analysis showed all of the pills with bogus holograms to be fakes. Some did contain a bit of artesunate, up to 12 milligrams per tablet, whereas genuine tablets have 50 milligrams. Such low doses, perhaps added to thwart simple authenticity tests, are particularly dangerous, Newton notes, because they can elicit resistance in the malaria parasite. Other pills contained no artesunate at all but a broad array of other active compounds--from paracetamol and chloroquine, an old malaria drug that's now useless in Southeast Asia, to safrole, a carcinogenic precursor to the party drug ecstasy.
Participating labs also analyzed minute quantities of pollen and nonactive mineral compounds present in the pills, which led them to conclude that they were most likely produced somewhere in southern China. All the evidence together suggested there were at least two producers of fake artesunates: one that made a "westerly group" of counterfeits found primarily in Myanmar, along the Thai/Myanmar border and northern Laos and another producing the "easterly group" found in Vietnam, Cambodia, and southern Laos. After INTERPOL presented the data to the Chinese government in March 2006, a criminal investigation led to two arrests later that year. One of those arrested was a native of Yunnan Province who allegedly bought 240,000 packages of fake artesunate, most of which he sold to Myanmar. The other was the seller of the drugs; the producer is believed to be still at large.
Whether the arrests reduced the amount of counterfeit drugs on Southeastern markets is unclear. For starters, the researchers think Chinese police may only have taken out the westerly trade route. There may be many more producers or routes than these two, says Valerio Reggi, an expert in counterfeit medicines at World Health Organization headquarters who was not involved in the operation. Still, international collaborations such as this one are key to tackling the problem, Reggi says. Its success helped inspire WHO to launch the International Medical Products Anti-Counterfeiting Taskforce in 2006.
Even so, says malaria researcher Nicholas White of Mahidol University in Bangkok, much more should be done to stop the flood of fake drugs. National governments should be more aggressive, for instance, and pharmaceutical companies should be required to tell drug-regulation authorities when they discover their drug is being faked; currently, many don't out of fear it will tarnish the product's image.
Most malaria experts agree that even the real artesunate produced by Guilin should come off the market as soon as possible. Although effective against malaria, WHO says artesunate should be sold only in so-called combination therapies to delay or prevent the advent of resistance in the malaria parasite.