Less than two months after counterfeit Avastin, a cancer drug made by the Swiss pharmaceutical giant Roche, was found on the US market, another fake version has turned up, health authorities said Wednesday.

The injectable cancer medication, bevacizumab, is labeled by the name under which Avastin is approved in Turkey, Altuzan, but contains no active ingredient, the US Food and Drug Administration said.

The agency "is alerting healthcare professionals that another cancer drug, originating from a foreign source and purchased by US medical practices, has been determined to be counterfeit," said the FDA in a statement.

"FDA lab tests have confirmed that a counterfeit version of Roche's Altuzan 400mg/16ml (bevacizumab), an injectable cancer medication, found in the US contains no active ingredient."

The sources blamed for distributing the drug were named as Richards Pharma, also known as Richards Services, Warwick Healthcare Solutions, or Ban Dune Marketing Inc (BDMI).

Richards Pharma is based in Britain, while Ban Dune Marketing is a now defunct company from La Jolla, California.

Earlier this year, the head of Ban Dune Marketing was indicted and pleaded guilty to a felony count of conspiring to distribute counterfeit prescription drugs.

An FDA spokeswoman said the agency has not confirmed if any US patients were given the counterfeit Altuzan.

The agency said any medical practice that has obtained products from the named distributors should stop using them and contact the FDA.

Avastin is used to treat colorectal, lung, kidney, breast and ovarian cancer and is among Roche's top-selling drugs with a turnover of 5.3 billion Swiss francs ($5.8 billion, 4.4 billion euros) in 2011.

In mid February, the FDA warned that as many as 19 US medical practices had potentially purchased and used counterfeit Avastin from Quality Specialty Products (QSP), a foreign supplier also known as Montana Health Care Solutions.

The only FDA-approved version of Avastin in the United States is marketed by Genentech, a subsidiary of Roche, and does not bear the Roche logo on its packaging, the agency said. Altuzan is not approved for use in the United States.

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