Tackling the trade in fake antimalarials
9 February 2009
The trade in fake antimalarial drugs harms many patients and increases the risk that drug resistance will develop. Working with INTERPOL, the WHO and a team of forensic scientists in 'Operation Jupiter', Paul Newton from the Wellcome Trust's South-east Asia Programme has helped to locate and shut down a distribution network of fake antimalarials in China.
Artesunate, used in many artemisinin-based combination therapies, is a vital weapon in the battle against malaria. But in countries with a large burden of malaria, such as Myanmar, Laos, Cambodia, Vietnam and Thailand (on the Thai-Myanmar border), as many as half of all artesunate tablets are fake.
Dr Newton has done much to publicise the scale and impact of the trade in counterfeit drugs. Recently, he teamed up with investigators from INTERPOL, representatives of the WHO and Chinese law enforcement agencies to analyse and trace the origins of fake artesunate.
In a unique 'forensic pharmacological' collaboration, six laboratories undertook a barrage of tests to analyse the composition of the fake drugs - and identify their possible origins - by assessing their chemical composition, gases around the tablets in blister packs and even the pollen embedded in the tablets during manufacture.
Many counterfeits were hard to differentiate from the genuine product, while others were poor copies (one managed to misspell 'tablet' on its packaging). Most of the fakes contained no artesunate, and some contained potentially toxic ingredients. Even more worryingly, some included sub-therapeutic amounts of artesunate or artemisinin, which, if consumed, could promote the spread of drug-resistant parasites.
The presence of a particular type of calcite and pollen flora in the tablets suggested that at least some of the counterfeits were made in southern China. Armed by INTERPOL with these findings, Chinese authorities made arrests in China's Yunnan Province in 2006. The suspects are alleged to have traded 240 000 blister packs of counterfeit artesunate.
Operation Jupiter depended on effective international collaboration and analytical techniques rarely available in South-east Asia. Without considerable extra resourcing it will be difficult to tackle the trade in counterfeit drugs, which are now also spreading across Africa. A partial solution may lie with portable detectors that can reliably determine whether medicines in shops and pharmacies do contain their stated active ingredient.
Image: Hologram on the packaging of fake antimalarials. From Newton et al., reproduced with permission from PLoS Medicine.
References
Newton PN et al. A collaborative epidemiological investigation into the criminal fake artesunate trade in South East Asia. PLoS Med 2008;5(2):e32.