UPDATE 2-GSK recalls prescription-only versions of heartburn drug Zantac

GlaxoSmithKline is recalling prescription-only versions of its popular heartburn medicine Zantac as a "precautionary measure" due to a probable cancer-causing impurity in the drugs, Britain's medicines watchdog said on Tuesday. The move follows an investigation by U.S. and European regulators into the presence of a potentially cancer-causing impurity in Zantac and generic versions known chemically as ranitidine, which are also used to treat stomach ulcers.

The U.S. Food and Drug Administration (FDA) said last week levels of impurity were "unacceptable". Britain's Medicines and Healthcare products Regulatory Agency (MHRA) said https://www.gov.uk/drug-device-alerts/class-2-medicines-recall-zantac-injection-50mg-2ml-zantac-syrup-150mg-10ml-zantac-tablets-150mg-zantac-tablets-300mg-el-19-a-24 GlaxoSmithKline (GSK) was recalling four prescription-only Zantac medicines: a syrup, an injection and tablets of 150 and 300-milligram dosages.

Over-the-counter products - Zantac 75 Relief and Zantac 75 Tablets - are produced by a different company and are not affected by the recall, it added. The MHRA said GSK was recalling all unexpired stock of the medicines from pharmacies due to possible contamination of carcinogen N-nitrosodimethylamine (NDMA).

The British company confirmed the recall. "GSK is continuing with investigations into the potential source of the NDMA," a company spokesman said, adding these investigations include continued engagement with its suppliers and with external laboratories to conduct tests on finished product batches of Zantac.

The MHRA said healthcare professionals had been told to "stop supplying the products immediately, quarantine all remaining stock and return it to their supplier". "We are advising that patients should not to stop taking their medication, and do not need to see their doctor until their next routine appointment but should seek their doctor's advice if they have any concerns," the MHRA said.

GLOBAL STOPPAGE

U.S. and European health regulators said last month they were reviewing the safety of ranitidine, after online pharmacy Valisure flagged the impurities to them.

The FDA said Valisure's higher temperature testing method generated very high levels of NDMA from the ranitidine drugs. After checking the over-the-counter drugs using a low-heat method of testing, the FDA said it found much lower levels of NDMA than was discovered with a higher temperature test employed by Valisure.

The U.S. regulator has asked ranitidine makers to conduct their own testing to assess levels of the impurity and to send samples of their products for testing by the agency. Swiss drugmaker Novartis halted global distribution of its ranitidine drugs last month.

Last week, Walmart Inc joined pharmacy chains CVS Health Corp, Walgreens Boots Alliance Inc and Rite Aid Corp in suspending the sale of over-the-counter heartburn drugs containing ranitidine. Canada's health authorities have asked makers of the drugs to halt distribution as they gathers more information. Last month, regulators in Hong Kong pulled four products, while in Ireland 13 products containing ranitidine were recalled.

NDMA had previously been found in some blood pressure medicines from a class of drugs known as angiotensin II receptor blockers, or ARBs. The impurity was believed to have been introduced by changes in the manufacturing process.

(This story has not been edited by Devdiscourse staff and is auto-generated from a syndicated feed.)