Fenbendazole As a Cancer Treatment

Fenbendazole (methyl N-(6-phenylsulfanyl-1H-benzimidazol-2-yl) carbamate) is a broad-spectrum benzimidazole anthelminthic drug used to treat various parasites in numerous animal species. It is also known to have moderate microtubule depolymerizing activity and a potent antitumor effect as shown in in vitro and in vivo experiments. Repurposing of veterinary drugs that exhibit promising results for human applications can significantly reduce the time and costs required to develop new medications.

A viral post on Facebook and TikTok has claimed that fenbendazole, a dog deworming medication, cures cancer in humans. The post cites an unlicensed veterinarian who makes videos showing a man using fenbendazole as a cancer treatment for his small-cell lung cancer. The videos have been removed from YouTube, Facebook and TikTok but remain available on other video platforms.

Several scientific studies show that fenbendazole can slow tumor growth in cell cultures and animals, but there is no evidence that it can eradicate established cancers or prevent them from recurrence. Health Feedback has previously analyzed the claims about Tippens’ anecdotal experience and found that there is insufficient evidence that he was cured by fenbendazole.

There are several reasons why a person might have an improved response to conventional cancer treatments while taking fenbendazole, including changes in their genetics and other factors that can influence a person’s response to the drug. There is also no evidence that fenbendazole prevents cancer from recurring after it has been treated with standard chemotherapy.

In addition to its known mode of action, fenbendazole has been shown to have synergistic effects when combined with RAPA, a potent anticancer agent. The synergy is attributed to the fact that fenbendazole and RAPA target different aspects of the cell’s metabolism.

Fenbendazole acts as a moderate microtubule depolymerizer and causes cancer cells to die by multiple mechanisms, while RAPA kills cancer cells by targeting mitochondria. The combination of the two drugs also results in a lower toxicity for both drugs.

A mPEG-b-PCL micelle was selected as the carrier for both FEN and RAPA at a molar ratio of 1:2, as the micelles were consistent in size and showed high encapsulation efficiency (EE) and drug loading capacity (DL). Both free FEN and FEN/RAPA-loaded mPEG-b-PCL micellar formulations demonstrated significant cytotoxicity against A549 cancer cells. The in vivo pharmacokinetic study showed that FEN-RAPA-loaded mPEG-b-PCL microspheres had a higher area under the plasma concentration-time curve from 0 to 2 h and a shorter half-life than free FEN or free RAPA.

To examine the antitumor effect of fenbendazole in vivo, female athymic nu/nu mice were xenografted with A549 tumours. The mice were administered oral fenbendazole every second day for 12 days. Tumours were excised, measured and weighed, and researchers observed reduction in tumour weight and size. The researchers also measured vascularity of the tumours and found that it was significantly reduced. The data suggest that fenbendazole inhibits tumor growth in vivo by inducing apoptosis and reducing blood flow to the tumor. These effects are mediated by the aforementioned synergistic effects and the oxidative stress response of cancer cells.fenben cancer treatment