WASHINGTON -- The FDA has issued an alert warning about counterfeit bevacizumab (Avastin) 400 mg/16 mL; the product does not contain the drug's active ingredient.

The agency notified 19 U.S. medical practices that purchased unapproved cancer drugs, including the faux bevacizumab, to stop buying through Quality Specialty Products, a foreign distributor that may also be known as Montana Health Care Solutions, the FDA said in a statement.

The bogus treatment was labeled as manufactured by Roche, which markets the drug outside of the U.S. FDA-approved versions of the drug are marketed in the U.S. by Genentech.

Lots of the fake drug can be identified with batch numbers starting with B6010, B6011, or B86017, the statement said.

Approved bevacizumab has six-digit batch numbers and expiration dates of three-letter month and four-digit year printed on the vial and packaging, and will not have a Roche logo.

The FDA has posted pictures of the counterfeit product on its website.