Cadila's Viona Pharmaceuticals pulls 2 metformin lots in U.S. over carcinogen fears

After the FDA last year discovered high levels of a likely carcinogen in the popular diabetes med metformin, a spate of manufacturers kicked off nationwide recalls. While those withdrawals have seemingly tapered off, the story isn't over for one Indian generics giant and its American subsidiary. 

Cadila Healthcare subsidiary Viona Pharmaceuticals is yanking two lots of 750-mg extended-release metformin from U.S. shelves after the batches were found to contain higher-than-allowed levels of the likely carcinogen Nitrosodimethylamine (NDMA). Cadila made the batches in India in November 2019 for Viona to distribute stateside, an FDA recall notice shows.

Metformin recalls became something of a trend last year, kicking off in earnest after the FDA in May urged five drugmakers to pull the popular diabetes drug over fears of NDMA contamination. Apotex, Actavis, Amneal, Lupin and Marksans started the recall parade, followed later in the year—and into 2021—by companies such as Bayshore Pharmaceutical, Sun Pharma and Nostrum Laboratories.

RELATED: Missouri's Nostrum Labs pulls more metformin over carcinogen concerns

As of Friday, Viona and Cadila said they hadn’t received any side effect reports linked to the suspect lots. Viona recommended that patients taking the affected product continue treatment and reach out to their doctor for an alternative. It can be dangerous to simply stop taking metformin, which is used to control blood sugar in patients with Type 2 diabetes, the FDA has said.

Viona shipped the two batches, which are due to expire in October, nationwide, the company said in its recall alert. The company’s metformin tablets come in 100-count bottles. Viona didn’t say how many bottles were affected, and the company didn’t immediately respond to Fierce Pharma’s request for comment.

Last February, the FDA found low levels of the likely cancer-causing contaminant NDMA in sample lots of metformin. At the time, the agency decided not to push for voluntary withdrawals of the products. One month later, online pharmacy and independent testing lab Valisure challenged the regulator’s findings and flagged NDMA contamination at unacceptable levels in 42% of the batches it checked. Valisure pushed for an immediate recall in a petition (PDF). 

RELATED: Lupin pulls diabetes drug metformin off shelves as carcinogen worries continue to build

The FDA’s call for withdrawal came in May, kicking off a spree of metformin recalls that continued into the latter half of the year. New Jersey’s Bayshore Pharmaceuticals jumped on board in August, recalling one lot each of its 500- and 750-milligram extended-release metformin after the regulator discovered high levels of the probable carcinogen in tested samples.

Marksans, which was involved in the FDA’s original recall action, added another 76 lots of metformin to its recall in October. More recently, Nostrum Laboratories kicked off a recall in November, which it expanded twice in January.