USFDA impact: DCGI asks states told to put antacids under scanner

After high blood pressure drug (sartan), the same carcinogenic impurity is back to haunt global pharma industry once again, this time for antacid ranitidine. On Tuesday, the Drug Controller General of India (DCGI) asked the state food and drug control administrations to verify the bulk drug and formulation (medicine) ranitidine made by manufacturers in their jurisdiction and take appropriate action to ensure patient safety. 

In its communication, the DCGI noted that it has been reported from other countries that some ranitidine products (a common antacid) contain a nitrosamine impurity called N-nitrosodimethylamine (NDMA) at low levels. NDMA is considered a probable human carcinogen (a substance that could cause cancer). The regulator asked the state drug administrations to verify the active pharmaceutical ingredients (APIs) and formulation of ranitidine made by manufacturers under their respective jurisdiction and take appropriate action. 

The ranitidine market in India is roughly around Rs 700 crore, with about 180 brands. GSK (Zinetac), Cadila Pharmaceuticals, JB Chemicals and Cadila Healthcare, being some of the major players in the domestic market. Some Indian players have already started taking action. 

Following the US Food and Drug Administration (USFDA) alert to patients and health care professionals, Hyderabad-based drugmaker Dr Reddy’s Laboratories (DRL) suspended worldwide supply of ranitidine as a precautionary measure. According to industry insiders, this is probably because DRL was selling the drug as an over-the-counter (OTC) medicine in the US, where it clocks $7 million in annual sales from the drug. European player Sandoz, too, had stopped distribution of the drug after regulators raised concerns.

“The other Indian formulation players who supply the generic version of Sanofi’s Zantac or ranitidine are prescription players. DRL was supplying the drug also as OTC and in that case monitoring and control can become difficult. Therefore, the suspension of supplies happened as a precautionary measure,” said a senior official of a drug firm that too supplies the drug to the US. He said all firms are in touch with the USFDA for updates on the agency’s decision. “This is an old molecule and does not constitute a significant portion of our US sales. If the USFDA issues any recall notice, drugmakers would comply immediately,” he added.

In mid-September, the USFDA issued a statement saying, “The USFDA has learned that some ranitidine medicines, including some products commonly known as the brand name Zantac, contain a nitrosamine impurity called NDMA at low levels. NDMA is classified as a probable human carcinogen, based on results from laboratory tests. NDMA is a known environmental contaminant and found in water and foods, including meats, dairy products, and vegetables.”

It says that it is working with international regulators and industry partners to determine the source of this impurity in ranitidine. “The agency is examining levels of NDMA in ranitidine and evaluating any possible risk to patients. The FDA will take appropriate measures based on the results of the ongoing investigation,” it says. The USFDA, however, has not asked patients to stop taking ranitidine at this time.

Major Indian drug firms that supply the drug to the US include Aurobindo, Wockhardt, Glenmark, Cadila Healthcare, Strides, Granules India, Ajanta Pharma, etc, says Deepak Malik, analyst with Edelweiss. “Most of the players do not have exposure beyond $1-2 million annually for ranitidine supplies. We do not foresee any major impact,” he adds. The market size for the drug in the US is estimated to be around $50 million. 

Global market size for the drug is estimated to be $400 million. After slipping over 3 per cent on Monday, DRL’s stock had closed day’s trade on the BSE down 1.6 per cent. The stock, however, recovered on Tuesday, closing at Rs 2,784.6, flat from previous close. Nifty Pharma index also remained flat on Tuesday, up 0.4 per cent.

Analysts feel the crisis is deeper for bulk drug players like Strides (it fell 2.8 per cent on Tuesday) that supply raw materials for ranitidine. Ranjit Kapadia, an independent pharma consultant, points out the NDMA is a water related impurity that can get into the bulk drug during the process of manufacturing. “The FDA needs to issue a directive on what is the permissible level of NDMA for daily intake. Manufacturers can take necessary action on sourcing only after that,” he said.