A new batch of counterfeit Avastin discovered in the United States was shipped from Britain after being purchased from a Turkish wholesaler by a British-based business, officials said on Wednesday.

The pattern of shipments from the Middle East via Europe mirrors an earlier episode involving fake versions of the Roche cancer drug in February, highlighting vulnerabilities in the global medicine supply chain.

Britain's Medicines and Healthcare products Regulatory Agency (MHRA) said it was looking into how the latest counterfeit batch entered Britain before being sold in the US market.

'It's an ongoing investigation,' said spokeswoman Jennifer Kyne. 'We're helping the FDA (Food and Drug Administration) with their investigation and doing all we can on our side.'

The British wholesaler purchased 120 packs of the medicine from a Turkish supplier, she added. There is no evidence to suggest that any of it reached patients in Britain.

The FDA said on Tuesday it had identified a new batch of bogus vials of the injectable cancer treatment containing none of Avastin's active ingredient, bevacizumab.

The fake versions of the Swiss drugmaker's top-selling product were labelled as Altuzan, which is the brand name that Avastin is sold under in Turkey. Kyne said the MHRA was informed on March 28 by the FDA that Altuzan batch B6021 was counterfeit.

A Roche spokesman said that authentic Altuzan only had Turkish-language packaging, whereas images of the fake medicine posted by the FDA on its website showed English-language packaging.

The FDA said US medical practices had bought the latest counterfeit Avastin from overseas suppliers, in particular 'Richards Pharma', and the MHRA said it was following up all potential lines of inquiry, including with Richard's Pharma, which is based in Warwick, central England.

A spokeswoman for the company, which is registered as a business involved in the 'wholesale of pharmaceutical goods', said no-one was immediately available to comment. – Reuters