The U.S. Food and Drug Administration said this week it notified 19 oncology practices they had purchased drugs from a supplier not approved by the agency, including a counterfeit version of Roche Holding AG's, Avastin, that did not contain the multibillion-dollar drug's active ingredient, bevacizumab.

The FDA and Roche's Genentech division said on Wednesday they were still investigating how widely the fake medicine was distributed. They do not know how many patients might have been affected, or if anyone was harmed.

Connie Jung of the FDA's Office of Drug Security said it was possible more practices could be involved.

"Clinics need to know who they're buying their medicines from, they need to make sure they're buying them from legitimate sources, licensed sources in the United States," she said.

The FDA said the drugs came from an overseas supplier called Quality Specialty Products, which does business in the United States with a distributor identified as Montana Healthcare Solutions.

Most of the doctors' offices contacted by the FDA are located in southern California, with one practice in Chicago and another in Corpus Christi, Texas. Several said they were scouring their inventories to see if they had any of the fake medicine and would monitor patients for any problems.

An official from one California oncology practice told Reuters it stopped buying drugs from Montana Healthcare in July when it noticed the products were missing a national health code necessary for billing and reimbursement.

"When we called Montana Healthcare to ask for their national health code they gave me the runaround. At that point we ceased all business," said the source, who asked not to be named because they did not have permission to speak to the media.

The practice did not contact the FDA at the time, but received a visit from agency officials a month ago who said they were investigating the supplier and that the medicines were being sourced abroad.

"They came in ... and said in the middle of my waiting room 'we got a problem,'" the official said of the surprise visit. "This story is horrific for me. I want to find out who the heck is doing this."

A list of expensive biotech medicines offered by Montana Healthcare Solutions and obtained by Reuters priced Avastin 400 mg vials for under $1900, compared with the nearly $2400 that Genentech charges in the United States. It listed Avastin under its Turkish brand name Altuzan.

The list offered "lower-priced European alternatives" of products from Amgen Inc, Eli Lilly and Co, Celgene Corp and Novartis AG. The company did not return telephone calls or e-mails seeking comment.

UK DISCOVERY

Jung said the FDA encountered a wide variety of fake drugs, from conventional pills to injectable medicines that need to be administered by a doctor. The trend is fueled in part by the high cost of certain medicines, pressuring patients and doctors to seek cheaper alternatives.

The FDA said it first found out about the bogus Avastin in late December after the UK Medicines and Healthcare Products Regulatory Agency alerted U.S. officials and Roche about the problem. Roche confirmed via testing earlier this week that the Avastin was fake, the FDA said.

The Beverly Hills Cancer Center, one of the 19 practices notified by the FDA, said it was in the process of determining whether it purchased any fake Avastin from Montana Healthcare.

"At the time the Center purchased drugs from MHS, we believed that the drugs were legal and approved and only recently learned from the FDA that some of the drugs may have been counterfeit or unapproved," the center said in a statement.

"The Center has identified no adverse effects for any of its patients who may have received drugs purchased from MHS," it said, adding it had no idea they were coming from overseas.

Genentech said it is monitoring side effect reports for any spike in safety issues that might arise from the fake Avastin.

The bogus Avastin distributed in the United States has several difference in its package and label that should make it easy to spot. For example, the counterfeit says Roche on the packaging and writing on the box is in French rather than English. Roche distributes Avastin outside the United States, but all legitimate Avastin meant for U.S. patients says Genentech.

The South Texas Comprehensive Cancer Centers said it has conducted a preliminary investigation of its records to assist the FDA. Executive Director Benno Kaufmann declined to say whether it did business with Montana Healthcare or whether it had uncovered any counterfeit Avastin in its investigation.

Genentech said it limits the distribution of many of its products and only sells directly to a defined number of fully licensed and contracted wholesalers and specialty distributors.

An expert on counterfeit medicines said clinics buying medicines from overseas or unapproved suppliers was becoming an increasing problem.

"What we've seen is that there are active efforts underway by persons to specifically target clinics and doctors," said Tom Kubic, president of the Pharmaceutical Security Institute, a non-profit, industry-supported organization that collects information on counterfeit medicines.

"We're well beyond the traditional counterfeit medicines we've seen in certain therapeutic categories," Kubic said, citing phony versions of erectile dysfunction drugs such as Pfizer Inc's Viagra.

(Additional reporting by Lewis Krauskopf in New York and Anna Yukananov in Washington; editing by Michele Gershberg and Andre Grenon)

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