Is Fenben the Cure For Cancer?

An animal deworming medication called fenben isn’t the cure for cancer, as a popular video claims. Despite the lack of any clinical evidence to support this claim, it’s still making the rounds online and is being sold in some stores, including Canadian pharmacies, Health Feedback has found. The claim stems from a viral video by a veterinarian who says she gave fenben to her terminal cancer patient and the cancer went into remission.

The animal dewormer fenben is in the class of medications called anthelmintics, which are used to treat parasites in animals. The drugs do not have human applications, and Health Canada lists them all for veterinary use only. A 2020 study did find that animal anthelmintics might have some anti-cancer properties, but turning these findings into a new drug would be a long journey.

A recent study using cancer cells and mice showed that fenbendazole works by disrupting the microtubules and by blocking cell growth. It also interferes with energy metabolism by preventing mitochondrial transporters from importing glucose, which is a key fuel for most cancer cells. It also causes p53 activation and modulates multiple other pathways that lead to effective cell death.

In the mouse model, fenbendazole reduced tumor volume by about a third when used alone or in combination with radiation. The authors rigorously analyzed the data to ensure that the results weren’t due to random chance or other factors. They found that fenbendazole reduced tumor growth by inhibiting the expression of GLUT transporters and hexokinase II, which are needed to import glucose for cell metabolism, and by causing autophagy.  fenben for cancer