does fenbendazole assist in controlling cancer?

The evidence for fenbendazole controlling cancer in humans is thin and indirect. No human trial was retrieved.

The only study in the evidence that directly tested fenbendazole against cancer was a 2024 mouse study on bladder cancer [1]. It used fenbendazole wrapped in nanoparticles and delivered directly into the bladder, not as an oral pill. In that mouse model, the combination treatment slowed tumor growth and improved survival [1]. The study also showed fenbendazole lowered a protein called PDL1 in cancer cells, which can help the immune system attack the tumor [1]. But mice are not people, and a local injection into the bladder is not the same as swallowing a tablet.

A 2005 lab study found that fenbendazole is not transported by a common drug-resistance protein called BCRP [2]. That means it might stay inside cells longer than some related drugs. But that is a lab finding about how the drug moves, not evidence it treats cancer.

The big gap is obvious: no human trials, no case series, no patient outcomes. The mouse study used a formulation and delivery method you cannot buy at a pharmacy. The idea that fenbendazole helps cancer comes from anecdotes and a plausible mechanism (it disrupts microtubules, similar to some chemotherapy drugs), but the retrieved evidence does not back it for human use.

My call: the evidence does not support using fenbendazole to control cancer in humans. What exists is a single mouse study using a specialized formulation, plus a lab finding about drug transport. Confidence: low.