Evidence Prompts FDA to Investigate Recent Cancer-Causing Substance in Diabetic Medication: Here’s Why!

Dr. Adam Tabriz

DiabetesPhoto byAuthor using Wonder App

Sitagliptin is the generic name for a medication used to treat type 2 diabetes in adults. The novel drug works by increasing insulin production, reducing glucagon secretion by the alpha cells of the pancreas, and reducing glucose release by the liver.

Sitaglipide is currently only prescribed solo under the brand name Januvia and in conjunction with metformin (another diabetic medication) as Janumet.

In August 2022, Merck, the manufacturer of the diabetic medication Sitaglipide, reported contamination of specific batches of their drugs.

According to the report published by FDA (Food and Drug Administration), the already distributed drug contained above the acceptable levels of nitrosamine impurity, Nitroso-STG-19 (also known as NTTP). Sitagliptin in the detected samples accounted for an intake limit of higher than 37 ng per day. In some cases, it reached 246.7 ng per day per patient.

Despite the acknowledgment of contaminated Sitagliptin batches FDA allowed “temporary distribution” of the medication. The agency states; the decision was to avoid a drug supply shortage.

Nitrosamines are a group of toxic chemicals that potentially damage genes and DNA in humans and animals, thus causing various cancers. The carcinogenic substance commonly occurs in human diets and the environment. However, the human body may be the host for its endogenous formation.

Research suggests that humans may be more susceptible to the cancer-causing effects of nitrosamines. Therefore, their higher levels of food and tobacco can increase the risk for certain malignancies like esophageal, stomach, and throat cancers.

Many nitrosamine substances are more potent carcinogens than others. One can account for over 30 different variations of nitrosamines in that list. These contaminants include NDMA (N-Nitrosodimethylamine), NDEA (N-Nitrosodiethylamine), and the animal tumorigenic NMBA (N-Nitroso-N-methyl-4-aminobutyric acid) categories.

In addition to Sitagliptin, there have been several other drugs that have been reported to the FDA with similar contaminants, including drugs used for heartburn (ranitidine, nizatidine), high blood pressure (losartan, valsartan, irbesartan), and diabetic medication (Metformin).

A certain level of nitrosamines is typical in the water people drink and the foods they eat, including cured and grilled meats, dairy products, and vegetables. That is why everyone has exposure to environmental nitrosamines to a certain degree. That includes the risk of drug contamination during the manufacturing process.

Merk, the manufacturer of Sitagliptin, has acknowledged the source of contamination. Nevertheless, the nature of that source needs to be clarified. The company states that they have already initiated the corrective action plans to fix the problem.

As of January 2023, Merk announces that it will carry out due diligence, remove carcinogenic containment from the medications, and ensure that future batches of drugs will be safe. Meanwhile, FDA authorized continual drug sales and distribution while the issue was under additional investigation.


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