U.S. FDA finds high levels of carcinogen in diabetes drug metformin

(Reuters) - The U.S Food and Drug Administration said on Wednesday it had found high levels of a possible cancer-causing impurity in some versions of the popular diabetes drug metformin.

The agency is reaching out to companies whose drugs had N-nitrosodimethylamine (NDMA) over accepted levels and will take appropriate action, a spokesman for the FDA said in an emailed statement.

Bloomberg, which first reported the FDA's findings, said that some recalls of metformin were expected as soon as this week, citing a person familiar with the matter.

Online pharmacy Valisure said in March that its independent tests showed high levels of NDMA in metformin made by 11 companies, including Amneal Pharmaceuticals Inc <AMRX.N> and Aurobindo Pharma Ltd <ARBN.NS>.

In December, the FDA had started an investigation into metformin, a drug is used as an initial treatment for patients with type 2 diabetes.

NDMA contamination was responsible for the recall of heartburn drug Zantac sold by Sanofi SA <SASY.PA> last year and some generic versions of the treatment last year.

(Reporting by Manas Mishra in Bengaluru; Editing by Amy Caren Daniel)