Fake Acomplia analysis reveals chemical cocktail

Researchers in Poland and the Netherlands have found that counterfeits of Sanofi-Aventis' obesity drug Acomplia (rimonabant) can readily be purchased over the Internet, despite being removed from sale in 2008.

They also report that analysis of the Acomplia products obtained indicate that while they tend to contain rimonabant in "effective quantities", the active is often accompanied by a mixed bag of impurities, unapproved polymorphs or other drugs such as sibutramine.

Pharmaceutical major Sanofi-Aventis withdrew Acomplia from sale in 2008 on concerns about increased levels of depression and suicidal thinking in patients taking the drug.

"Rimonabant was withdrawn from the market because of serious adverse events and lack of efficacy," write the authors.

"The availability of poor quality products with rimonabant, impurities and unapproved polymorphs is worrying."

The researchers analysed tablet samples from five Acomplia products purchased online using a technique known as LC-DAD-MS (liquid chromatography with diode array detection and mass spectrometry detection) with additional measurements using near infrared (NIR) spectroscopy, X-ray diffraction and Raman spectroscopy.

Four of the five samples contained rimonabant, but two also had an unapproved rimonabant analogue, two contained an unapproved polymorph and one contained low doses of another drug used to treat obesity - sibutramine - as well as traces of sibutramine analogues.

Sibutramine has also been found in counterfeit versions of GlaxoSmithKline's over-the-counter weight-loss product Alli (orlistat).

Reference:  Journal of Pharmaceutical and Biomedical Analysis (in press)