A day after fake batches of Eli Lilly’s antipsychotic Zyprexa were discovered in the supply chain, the UK’s health regulator has issued a warning about counterfeits of Sanofi-Aventis and Bristol-Myers Squibb’s clotbuster Plavix being smuggled into the country as parallel imports.

The Medicines and Healthcare products Regulatory Agency said that in conjunction with the European Medicines Agency, Sanofi and BMS, it is recalling “any parallel distributed stock of lots 3098 and 6Y098” of tablets branded as Plavix (clopidogrel), “following the discovery of counterfeit tablets in the legitimate supply chain”. The MHRA goes on to note that, as with the counterfeit batches of Zyprexa (olanzapine), the fake Plavix “was supplied in French livery via parallel distributors into the UK supply chain”.

The agency added that “stock presenting a patient risk may be present as French livery cartons with an overlabel applied by a parallel distributor or may have been recartoned into an English carton by the parallel distribution repacking process." The aforementioned lots are genuine numbers used by Sanofi and BMS for which the original unchanged lots were supplied to France in French livery, the MHRA added, noting that the EMEA has allowed in excess of 30 UK parallel distributors to supply Plavix.

Although the MHRA has not confirmed anything, the similarity of the Zyprexa and Plavix cases could suggest that the same counterfeiter is behind both fakes. However the agency did say the initial tests showed that the Plavix samples only contain about 70% - 80% of the labelled active ingredient and while work is ongoing to obtain more information, “in the interim we consider a recall is needed to minimise patient risk”.

Two cases in as many days have once again highlighted the problem of fake drugs. Speaking about the Zyprexa case, David Pruce, director of practice and quality improvement at the Royal Pharmaceutical Society Of Great Britain, said that “counterfeiting in the UK is a rare occurrence but nevertheless a world-wide problem. The Society has been working with the MHRA through our team of inspectors and we ask pharmacists to cooperate with the MHRA's investigation and to be alert for counterfeit medicines."

However there are other people who feel that the problem in the UK is not so rare and earlier this year, the MHRA said it was investigating 25 cases of counterfeiting, which is twice the number it had to deal with five years ago. Pfizer has claimed that its move to a single drug distribution channel in the UK with a sole supplier, Boots' Alliance UniChem, was provoked by counterfeit Lipitor (atorvastatin) entering the supply chain last year and a number of other pharmaceutical companies have since stated their intention to evaluate their distribution models.