Mebendazole - Tumours and Tapeworms

There’s a big push by some in the cancer research community to look at old drugs to see if they’ve got some anti-cancer activities. It makes a huge amount of sense to do this as it short circuits all of the phase I trials to test a drug’s toxicity, often these drugs are cheap generics and there’s many years of data on pharmacokinetics and side effects and so on. It means that in a best case scenario you can cut out years of preliminary work. Some of the drugs, like the anti-diabetic drug Metformin or plain old Aspirin also have evidence of anti-cancer effects in the population rather than just from test-tube experiments or computer simulations. And the good news is that the list of such drugs is growing longer by the day, and the evidence continues to mount up that some of the best candidates will enter use soon either as support to existing treatments or, in some cases, as part of new protocols to prevent recurrence of disease after treatment.

One of the more surprising drugs in Mebendazole, an old drug that has been around for a long time as a treatment for parasites like tape-worms. Mebendazole, which is available over the counter in any case, has got a surprising amount of evidence in its favour as an anti-tumour drug. This evidence comes from modelling the molecular profile of the drug to see how it fits with particular cancer pathways, from experiments in test tubes and in animal testing using human tumours. As pre-clinical evidence goes, that’s pretty much the works.

A recent paper in the journal Neuro-oncology, found that:

…we showed that mebendazole significantly extended mean survival up to 63% in syngeneic and xenograft orthotopic mouse glioma models. Mebendazole has been approved by the US Food and Drug Administration for parasitic infections, has a long track-record of safe human use, and was effective in our animal models with doses documented as safe in humans. Our findings indicate that mebendazole is a possible novel anti-brain tumor therapeutic that could be further tested in clinical trials.

The full paper has been published with open access and can be downloaded here: http://neuro-oncology.oxfordjournals.org/content/13/9/974.long

But it’s not just animal models, a recently published case showed that a cancer patient who had reached the end of the line with standard treatments for adrenocortical carcinoma was treated with 100mg twice a day, and had disease stabilisation and a good quality of life for 24 months with this as his only treatment. One case is not enough to bring the drug into the mainstream, but it’s a remarkable result for someone who had no other options open to them. The non-toxic nature of the treatment, and the low cost, are in stark contrast to the treatments that had preceded it.

The range of cancer types that have shown a response to Mebendazole in the test tube is similarly impressive.

Given all of this evidence it seems that this is a drug that ought to go into clinical trials as quickly as possible. And that’s where we hit a stumbling block. Formal drug trials cost an awful lot of money, and very often require a commercial sponsor. A generic drug is not going to have that sponsorship. But, to my mind at least, this is where our taxes and our charity giving should step in. We give millions for cancer research, either through the tax system or directly to charities, this is the money that should be funding this work. Why isn’t it happening?