The US FDA has found a cancer-causing substance, NDMA, in Ranitidine-based medicines like GSK’s Zinetac, and is probing the matter.

New Delhi: British drug-maker GlaxoSmithKline (GSK) Pharmaceuticals has decided to suspend the supply of India’s second-largest brand of acidity and heartburn medicine, Zinetac, following the on-going probe by the US Food and Drug Administration (US FDA) into the reported cancer-causing impurity in Ranitidine-based drugs.

The company is also set to initiate a voluntary recall of Zinetac tablets (150 mg and 300 mg) at the pharmacy level.

Ranitidine is commonly prescribed by doctors in India to cure acid-related cough, indigestion, stomach pain and heartburn. Cadila Pharmaceuticals’ Aciloc is the top-selling brand, followed by Zinetac and JB Chemical’s Rantac, according to the research firm AIOCD PharmaTrac. Other popular brands are R-Loc and Ranitin.

According AIOCD PharmaTrac, Zinetac’s turnover in the year ending August 2019 was more than Rs 200 crore.

“GSK has been contacted by regulatory authorities regarding the detection of genotoxic nitrosamine NDMA in ranitidine products,” a GSK spokesperson told ThePrint in an emailed response.

NDMA is classified as a probable human carcinogen — a substance that could cause cancer.

“Based on the information received and correspondence with regulatory authorities, GSK made the decision to suspend the release, distribution and supply of all dose forms of ranitidine hydrochloride products to all markets, including India, as a precautionary action, pending the outcome of ongoing tests and investigations,” the company said.

GSK is the second company to halt the supply of Ranitidine-based drugs after Dr Reddy’s Laboratories Sunday suspended the supply of the drug worldwide.

Also read: After US red-flag, Modi govt asks states to check samples of acidity drug for cancer agent

Voluntary recall

For supply to the Indian market, GSK manufactures Zinetac using raw material or active pharmaceutical ingredients from Hyderabad-based Saraca Laboratories and SMS Lifesciences.

However, the GSK spokesperson said the company had been informed that “Saraca Laboratories Limited were notified by the European Directorate for the Quality of Medicines (EDQM) that its certificate of suitability for ranitidine hydrochloride has been suspended with immediate effect”.

“Hence, based on the information provided and as a precautionary action, GSK has made the decision to initiate a voluntary recall (pharmacy/retail level recall),” it said.

GSK is not planning to recall the drug manufactured using APIs from the other supplier, SMS Lifesciences, right now, but said “all such products will remain on hold and they will not be released to the market while we await the test results”.

“GSK is continuing with investigations into the potential source of the NDMA. These investigations include continued engagement with our API suppliers. Patient safety remains our utmost priority and we are taking this issue very seriously,” it said.

US FDA alert causing storm across globe

The US FDA said on 13 September, “Some ranitidine medicines, including some products commonly known as the brand name drug Zantac, contain a nitrosamine impurity called N-nitrosodimethylamine (NDMA) at low levels.”

However, the FDA is still evaluating whether the low-levels of NDMA — found in both the generic and brand versions of ranitidine — pose any kind of risk to patients.

It has also advised patients to “trust that their medicines are as safe as they can be and that the benefits of taking them outweigh any risk to their health”.

Those who wish to discontinue using the medicine should talk to their healthcare professionals about other treatment options, it said.

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