Can Dog Deworming Medicine Treat Breast Cancer?

00:00:11 Speaker 1 Announcer
Welcome to the breastcancer.org podcast, the podcast that brings you the latest information on breast cancer research, treatments, side effects and survivorship issues. Through expert interviews as well as personal stories from people affected by breast cancer, here’s your host breastcancer.org senior editor Jamie Depolo.
00:00:29 Speaker 2 Jamie Depolo
Hello, thanks for listening. Our guest today is Brian Wojnowski, MD, who practices medical oncology in Delaware County, Pennsylvania at Riddle, Taylor and Crowser Hospitals and also serves as breastcancer.org’s medical advisor. A native of South Philadelphia, he trained at Temple University School of Medicine and Lankenau Medical Center. Dr. Wojnowski as a sought after.
00:00:50 Speaker 2 Jamie Depolo
Speaker on the topics of medical ethics and the biology of cancer in this what my patients are asking podcast. We’re going to talk about stories in the popular media about using Fenbendazole, a drug use to deworm dogs to treat cancer. Doctor Wojo, welcome to the podcast.
00:01:09 Speaker 3 Dr. Wojnowski
Thank you, Jamie. Thanks for having. Me.
00:01:11 Speaker 2 Jamie Depolo
Of course, now I personally have used fenbendazole to treat one of my dogs who had hookworms and in our stage 4 metastatic breast cancer discussion Board forums, some people have been talking about using that drug fenbendazole to treat cancer.
In the stores, FENBENDAZOLE is sold as Panacure and Safeguard and it’s used to treat a variety of parasites, as I said, including roundworms, hookworms and whip worms in dogs, and I think there are some studies in Petri dishes that suggest fenbendazole.
Might have anti cancer properties. I don’t know of any studies done in people. I did kind of a quick search. So can you tell us, Doctor Rojo, a little bit about this drug? What does it do in the body? And I guess what I’m thinking most importantly is, is it is this really safe for people to be taking?
00:02:10 Speaker 3 Dr. Wojnowski
Yeah, there’s a lot of good questions wrapped up in there and I will just start by saying that fenbendazole is a drug that I was already familiar with because I’ve given it to my dog like you have.
It’s it, the technical name for the drug is well for the class of drug is anthelmintic.
A fancy way of saying that it, it kills worms. It kills worm parasites in dogs. I think what happened was a couple of years ago it was accidentally noted that this drug had anti-cancer properties.
And it’s it’s actually a really interesting story and a really interesting drug because the first time I heard about it, I thought to myself, Oh my goodness, OK, people are taking the dog medicines now. What’s, what’s going on with this? What kind of crazy stuff is this? But that it’s an investigation.
And and it turns out. That this drug actually has a feasible mechanism that it could actually have anti-cancer properties it. Turns out the way it works is it inhibits microtubules and microtubules are basically part of the skeleton of cells. They hold the cells together.
And basically keep them inflated and, and provide structural support to cells and of course cancer cells need that structural support to survive just like normal cells do.
And this drug inhibits those, and that’s how it kills these worms.
Now, what was happening a couple of years ago, they did a study at Johns Hopkins and they had these mice that were, were completely immunosuppressed. They had no immune system. So these mice would be inoculated with tumors. And because there was no immune system, the tumors would grow easily in the mice.
And then the researchers could test various cancer drugs against these tumors. So where they where they testing fenbendazole against the tumors. No, actually the fenbendazole, because it was actually an antiparasitic was actually being given to the mice in their food.
And they noticed that the ones that got this fenbendazole, the tumors wouldn’t grow. So then they started testing and you know, giving some mice fenbendazole and some mice didn’t get fenbendazole and they found that there was a there was a real signal there that the fenbendazole seemed to be helping kill these tumors in these mice.
00:04:52 Speaker 2 Jamie Depolo
Ohh wow. Well, I have a question too now. You said it’s a microtubular inhibitor, does it just inhibit the microtubules in the cancer cells, or does it go out and do things to healthy cells as well? I mean, how does it know?
00:05:08 Speaker 3 Dr. Wojnowski
It doesn’t seem to affect the healthy cells as much because cancer cells are growing rapidly and there’s a lot of turnover with the microtubule so as is the case with just about any cancer drug, it affects tumor cells more so than normal cells, because those are the cells that are rapidly dividing and using the microtubules to a greater degree. So in theory it should be fairly specific to the cancer cells, but we’re not really sure and I’ll get to that more in a little bit.
00:05:43 Speaker 2 Jamie Depolo
So we have this study looking that there’s potential in mice, but there have been a lot of studies with drugs that have potential in mice and then don’t pan out in people because of side effects or or other things. So, is any research on people moving forward? Because I know there are like I would be nervous about taking a medicine for a dog because I know there are certain medicines that I take like ibuprofen, that would kill my dog. So, I’m assuming that there’s, you know, some of that same problem going back and forth between species.
00:06:21 Speaker 3 Dr. Wojnowski
That’s exactly right. And the thing about it is the bottom line is that we don’t have any good studies in humans.
And mice and pinworms are not simply tiny human beings. They are different organisms. And for example, the liver of the mouse may process the drug totally differently than the liver of a human being, and like you said, there’s many drugs that have shown promise in mice, but it’s not really panned out in human beings. I mean, it probably happens every day out there.
Where you know in in, in the lab, when you’re when you have mice and you’re testing these drugs on mice, they show promise. And then when they finally make it up to human beings, very, very few of these drugs actually work in humans. And the reason is, is because a human being with cancer is a very different organism than a mouse with no immune system.
00:07:20 Speaker 2 Jamie Depolo
Right, right, right. And I did, you know, when I was doing some research on this, I did come across a blog and I think this is where some of this not all, but some of this started. So there was a man you may have heard of him. His name is Joe Tippins.
And he was diagnosed with metastatic small cell lung cancer, and his prognosis was bad. He had a very poor prognosis. So according to his blog, a veterinarian told him about these fenbendazole studies and how it it was killing cancer cells in mice and Joe figured he had nothing to lose. He had a poor prognosis. He had metastatic disease. Let’s try it. And so we started to take it. He’s still taking it as far as I understand from his blog, which I just checked last week. He’s taking it as maintenance and according to his blog, he has no evidence of disease. Now I can imagine for anyone who’s been diagnosed with metastatic cancer, this is a hugely, hugely powerful story.
But I guess you know I, you know, as we said, you know, we don’t know the side effects in people and I guess I’m also wondering, you know Joe had small cell lung cancer and I guess I’m wondering is it possible that that particular cancer is possibly more susceptible to fenbendazole, then breast cancer, and I asked that because it seems like several, a lot, of most of the new immunotherapies that are coming out seem to work so well in lymphomas and lung cancer, but they don’t really work that well in breast cancer.
So do we know anything about that? And if we don’t, that’s fine. I’m just. I’m curious.
00:09:17 Speaker 3 Dr. Wojnowski
Yeah. So you know, I mean, small cell lung cancer, metastatic is a devastating disease.
And on average, people live only about 9 to 12 months with that particular cancer. But every oncologist has seen a small percentage of people say maybe 5% who live, you know, up to five years with this disease.
And there could be a lot of different reasons for that. You know, some every, you know, even within small cell lung cancer, everyone is different and everyone will respond to different treatments in different ways. So the one possibility, of course is that the fenbendazole works.
OK. We can’t we can’t discount that possibility.
The other possibility is that the other chemo drugs that he was on, which may also have anti microtubule activities, for example Taxol has anti microtubule activities just like fenbendazole. So if he was on that drug, you’d have to ask the question well. Yeah, maybe was the taxol that did it. Which has similar properties.
You know, so it’s hard to know for sure. You know, I’m not his doctor. I don’t know the details of, of his case, but my patients asked me about these sort of things all the time. And I’m not going to stand in any ones way. I’m not gonna, I’m not gonna say you can’t take XYZ medication, but on the other hand, people ask me for my advice based on my experience and expertise, and when patients ask me about these things, my answer is it usually goes something like this.
Well, it hasn’t been said in human beings, so we don’t know if it helps, but almost as important, we don’t know if it’s harmful either.
So, I would never want to recommend to my patients anything that I was uncertain about, especially when there are other medicines and treatments which we do have good studies and we do have a lot of good data and information as to whether or not it helps and what the side effects are.
00:11:34 Speaker 2 Jamie Depolo
OK, now are any of your patients that you know of taking fenbendazole?
00:11:41 Speaker 3 Dr. Wojnowski
No, not that I’m aware.
00:11:42 Speaker 2 Jamie Depolo
Of OK, because I guess I was just wondering too and we probably don’t know the answers to these like can you take too much of it? I mean there’s really not a human dose. I know what the dose is for a 50 pound dog and, and the I guess the other thing too, I wonder is what are the interactions with anything else someone might be taking.
00:12:02 Speaker 3 Dr. Wojnowski
We have no idea that’s the problem. We have no idea. And the first principle in medical ethics is do no harm.
00:12:13 Speaker 2 Jamie Depolo
Right.
00:12:14 Speaker 3 Dr. Wojnowski
So as a physician, I’m going to want to really be able to understand what the potential side effects are for my patients. So I’m not likely to recommend this drug for my patients right now, even though it is a very interesting drug with a mechanism of action that could have some potential, and it’s not unheard of to discover chemo drugs or other drugs, sort of serendipitously, or by accident in this manner. Cisplatin is one of the most important chemotherapy drugs, and you know, that was discovered accidentally when scientists was studying the effects of electric fields on cell division, he found out that when he turned on the electric field, the cells stopped dividing.
But the electrodes were made from platinum, and it turned out it wasn’t the electric field that was causing the cells to stop growing, but it was actually the platinum that was being released into the solution. So yeah, I mean, it certainly is a very interesting drug with an interesting and maybe even feasible mechanism of action. But until we have the studies in human beings, and we know if it really works, or and whether or not it’s safe, I just can’t recommend it.
00:13:30 Speaker 2 Jamie Depolo
OK. OK. Thank you for that. And I guess I’m wondering too, do you know of any studies that may be looking at fenbendazole and cancer in people is, I mean, are people talking about it or considering it, you know?
00:13:45 Speaker 3 Dr. Wojnowski
I don’t know any studies specifically that are looking at that right now.
00:13:50 Speaker 2 Jamie Depolo
OK. OK, so in your opinion and I don’t want to put words in your mouth, but it sounds like you are not recommending this to your patients now and it’s really kind of a we need to wait and get more information.
00:14:03 Speaker 3 Dr. Wojnowski
That’s correct. And you know the other thing is we do have chemo drugs out now that if that target the microtubules, just as Fenbendazole seems to do so you know if a patient asked me about it, I would probably go in that direction.
00:14:17 Speaker 2 Jamie Depolo
OK. Thank you very much, Doctor Wojo, really appreciate your insights on this. This is going to be very helpful.
00:14:25 Speaker 3 Dr. Wojnowski
You’re welcome, Jamie. It’s been a pleasure.