The Food and Drug Administration is warning U.S. doctors about another counterfeit version of the cancer drug Avastin, the third case involving the best-selling Roche drug in the past year.

The FDA said in an online post Tuesday that at least one batch of the drug distributed by a New York company does not contain the active ingredient in real Avastin, which is used to treat cancers of the colon, lung, kidney and brain. The drug was distributed by Medical Device King, which also does business as Pharmalogical. The vials are packaged as Altuzan, the Turkish version of Avastin that is not approved for use in the U.S.

The agency warned doctors in April about a similar case of fake Turkish Avastin distributed by a U.K. distributor. Prior to that, the FDA announced in February an investigation into a different batch of fake Avastin distributed to doctors in several states. Both of those cases appeared to involve different networks of distributors than the latest incident.

The FDA said it's currently unclear whether any U.S. patients have received the drug. Specifically, Altuzan labeled with the lot numbers B6022B01 and B6024B01 may be counterfeit. Importing even authentic Altuzan into the U.S. is illegal, since the FDA has only reviewed Avastin as safe and effective.

The agency is asking doctors to stop using any products from Medical Device King, Pharmalogical or Taranis Medical, another affiliated business.

A telephone number listed on Medical Device King's website was not in service. Company representatives did not immediately respond to emails sent Wednesday.

Roche's Genentech unit sells Avastin in 120 countries and manufactures and packages the drug at eight sites worldwide. The drug had sales of $5.8 billion in 2012 and was Roche's second-best selling drug overall. The injectable drug usually sells for about $2,500 per vial.

The FDA warned doctors to be wary of drug prices that seem "too good to be true."

"Deep discounts may be offered because the product is stolen, counterfeit, substandard, or unapproved," the agency states.

Incidents of counterfeiting reported by drugmakers have increased steadily over the past decade, though only about 5 percent of cases are typically reported in the U.S. The rise in counterfeiting comes as pharmaceutical supply chains increasingly stretch across continents. More than 80 percent of the active ingredients used in U.S. pharmaceuticals are now manufactured overseas, according to a recent congressional report.

FDA

White, round pills marketed as Teva's 30-milligram Adderall are counterfeit, the Food and Drug Administration warned Tuesday.

Federal health officials are warning consumers and medical providers about fake versions of the ADHD drug Adderall being sold on the Internet.

The counterfeit 30-milligram tablets contain the wrong active ingredients, according to preliminary laboratory tests by the federal Food and Drug Administration. Instead of containing the four active ingredients in prescription Adderall, the fake tablets contain only tramadol and acetaminophen, medications used to treat acute pain.

Teva Pharmaceutical Industries Ltd., the manufacturer of Adderall, which is used to treat attention deficit hyperactivity disorder and narcolepsy, contacted the FDA after a consumer reported buying the counterfeit drugs online. Authentic Adderall is a controlled substance that requires special dispensing controls for pharmacists.

The counterfeit drugs are round, white and do not have any type of markings, such as letters and numbers. Authentic Adderall 30-milligram tablets are round, orange or peach and scored, with “dp” embossed on one side and “30” on the other side of the tablet. The Teva products are packaged only in a 100-count bottle with National Drug Code 0555-0768-02 listed.

In addition, the fake drugs are sold in blister packs and they have misspellings on the packaging, FDA officials said.

Adderall and other ADHD medications have been in short supply and listed on the FDA’s drug shortage list for more than a year. The authentic drug contains four ingredients: dextroamphetamine saccharate, amphetamine aspartate, dextroamphetamine sulfate and amphetamine sulfate. The FDA and drugmakers have blamed problems with the supply of the active pharmaceutical ingredients for the dearth of the product. Teva continues to ship the drug as it becomes available.

It’s possible the shortages have prompted consumers to seek alternative sources for the drugs. The FDA urged extra caution buying drugs online.

"The counterfeit versions of Adderall should be considered unsafe, ineffective and potentially harmful," FDA officials said in a statement. 

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