A patient who has developed valsartan colon cancer as a result of taking the hypertension medication may be eligible to pursue legal action against the drug manufacturers.

What is Valsartan?

Valsartan and other drugs with the element “sartan” in their names, including losartan (Cozaar), irbesartan (Avapro) and olmesartan (Benicar) are part of a class of drugs known as angiotensin II receptor blockers, or ARBs. Primarily used to treat high blood pressure, ARBs such as valsartan are also indicated for diabetic nephropathy (diabetic kidney damage) and congestive heart failure. According to the Mayo Clinic, these medications are given to patients who are unable to tolerate ACE inhibitors.

ARBs work by preventing the action of the hormone angiotensin, which causes blood vessels to constrict. They accomplish this by deactivating the receptors that are found in the smooth muscle cells of the veins and arteries. In 1995, the U.S. Food and Drug Administration (FDA) approved the first ARB medication, Benicar. The drug is generally well-tolerated with few side effects.

Valsartan Colon Cancer

Recent cancer concerns have nothing to do with the medications themselves, but rather a chemical contamination — known as N-Nitrosodimethylamine (NDMA) — that has been discovered in certain lots from different drug companies.

The contamination was first noted in July 2018. A known carcinogen, NDMA is part of a group of chemicals called nitrosamines, which are used in the production of industrial lubricants and aviation fuel, and occur naturally in smoked meats and tobacco fumes. Since then, according to Drug Safety News, similar chemical contamination has been found in batches of losartan and irbesartan as well.

The contamination was initially traced to a factory in China, where changes in the manufacturing process appear to have resulted in a chemical reaction that caused the formation of nitrosamines. More recently, the FDA issued a warning letter to a facility in India after an inspection there revealed “significant deviations from current good manufacturing practice,” making nitrosamine contamination more likely.

Another Carcinogen Detected

In June of last year, online pharmacy Valisure reported it found dimethylformamide (DMF) in samples of valsartan made by more than one company, according to Bloomberg.

DMF is a solventused to create certain plastics and acrylic fibers. It also has been used to chemically synthesize pharmaceutical drugs. The World Health Organization classifies DMF as a “probable human carcinogen.”

Valsartan pills made by Swiss pharmaceutical company Novartis AG were among those that tested positive for DMF, according to an FDA filing made by Valisure. The online pharmacy said at the time that its tests found DMF in some versions of valsartan that had not been recalled due to NDMA, so as a result, some of the DMF-tainted drugs had been among those recommended by the FDA as alternatives to NDMA-tainted drugs, according to last year’s report by Bloomberg.

Novartis makes Diovan, which is the brand name of valsartan.

Even though some of the drug companies said they don’t use DMF to manufacture valsartan, they don’t all have control of the medications from start to finish in the supply chain.

Sometimes raw ingredients need to be broken down in order to be combined with other ingredients and formed into a pill. If chemical solvents are used, it’s with the intention that the solvent will dissipate before the final product has materialized. DMF allegedly is a less expensive pharmaceutical solvent than some on the market today.

Bloomberg’s article made it clear that Novartis does not use DMF to create Diovan and neither do its suppliers, but the suppliers’ suppliers might use DMF to form the inactive ingredients used to create the final product.

Other Valsartan Dangers

In addition to valsartan colon cancer, drugs in this class have also been linked to cancer of the esophagus, gastrointestinal tract, pancreas, prostate, kidney, and liver. The FDA recently published an announcement, stating that the cancer risk from contaminated ARB drugs was probably lower than the agency’s original estimates suggested.

According to current FDA estimates, there may be one additional case of valsartan colon cancer or another malignancy among 8,000 patients taking the medication at the maximum daily dose of 320 milligrams over a four-year period. A reason for the revised estimate is that not all ARBs have been affected; furthermore, many patients have turned in the contaminated products in response to voluntary manufacturer recalls.

Should You Stop Taking Valsartan?

While the risk of developing valsartan colon cancer or another form of the disease is low, it is not negligible. On the other hand, patients should not discontinue taking any prescribed medication without first discussing it with their doctor. A wise course of action is to consult the FDA website to determine whether or not your valsartan as been affected by the contamination.

Have Valsartan Lawsuits Been Filed?

Neural IT explains that a patients have already filed lawsuits saying that they developed cancer as a result of contaminated valsartan use. One such lawsuits was filed on January 30, 2019, in the U.S. District Court for the Western District of Arkansas. In the lawsuit, Betty S. says that she developed colorectal cancer from taking valsartan pills that were contaminated with NDMA.

She aimed to take the drug’s makers and distributors to task for their alleged liability in her cancer claims. In her claim, she elaborates on her valsartan use, saying that she began taking the the drug in September 2018. Allegedly, she used various generic versions of the drug until August 2018.

She goes on to recount that starting in July 2018, the FDA began implementing a number of valsartan recalls. She then said that she was diagnosed with colorectal cancer in September 2018.

Allegedly, her experience with valsartan use and colorectal cancer was consistent with the FDA’s explanation of the possible timeline of valsartan colon cancer. Neural IT states that the FDA expressed that patients who took valsartan were not at immediate risk of developing cancer, but might see this serious side effects around four years after using the drug.

According to Betty, her experience with taking valsartan and being diagnosed with colorectal cancer was in line with this projected timeline provided by the FDA.

The month that Betty was diagnosed with colorectal cancer, she claims, was the same month that the FDA discontinued all medication and drug ingredients made by  Zhejiang Huahai Pharmaceuticals in China, the manufacturer allegedly connected to a large amount of the contamination.