Ivermectin and breast cancer: a combination that’s raising new questions and possibilities in treatment. Let’s dive into the latest findings.

First a little background on this drug.

Ivermectin is an anti-parasitic drug first discovered in the 1970s by Japanese scientist Satoshi Omura. He found it in a rare bacterium called Streptomyces avermitilis, in the soil. He was able to successfully culture it in the laboratory and later partnered with William C. Campbell at US-based Merck & Co, and together they turned this microbial discovery into a breakthrough antiparasitic wonder-drug. It later earned them the 2015 Nobel Prize in Physiology or Medicine.

Ivermectin was made commercially available by Merck in 1981 for use in veterinary medicine. It was then approved for human use in the late 1980s.

Ivermectin is called an anthelmintic drug because it is a parasite destroyer — its main method of action is to interfere with the nerve and muscle functions of invertebrates like worms, lice etc, thereby paralyzing and killing them. But that’s not all it does.

Emerging studies have suggested that its role goes beyond that of just an anti-parasitic drug, indicating that it may help treat inflammatory conditions, viral infections (it became hugely popular during COVID), and even cancer, which is why I’m sharing it with you.

Ivermectin is gaining quite a bit of interest in oncology — not as a cure, but for being a potential partner to existing treatments. More on that shortly. Here are some of the main features of Ivermectin, along with the research.

Anti-Inflammatory

Ivermectin is known to play an immunomodulatory role that suppresses inflammatory responses in humans. Its main method of action is to inhibit the nuclear factor kappa-light-chain enhancer of activated B cells (NF-kB) pathway, preventing the cascade of IL-17 and reducing the expression and secretion of proinflammatory cytokines such as IL-1 and TNFalpha [1], [2].

Anti-Viral

Ivermectin has been studied for its effects on viruses including human immunodeficiency virus-1 (HIV-1), dengue fever, West Nile virus, and SARS-CoV-2 (COVID-19) (among others). [3]

Ivermectin gained significant attention during COVID-19 when it was discovered that its mode of action was to inhibit viral protein transportation in cells. That, together with its anti-inflammatory properties made Ivermectin look pretty awesome. Remember the discussion about “cytokine storms” in severe COVID-19 cases? Ivermectin was shown to have the ability to inhibit STAT-3, a protein involved in cell signalling and gene regulation, a central player in these so-called cytokine storms. [4]

The 2021 study at [3] reported that of the 115 patients in the trial, none of those who received a single dose of Ivermectin went on to develop cardiovascular or pulmonary complications, while in 133 control patients (those who did not receive Ivermectin), 9.8 percent developed pneumonia, and 1.5 percent had an ischemic stroke. The same study revealed that patients treated with Ivermectin became COVID-19-negative in a short time – about four days – compared to 15 days in control patients. Exciting stuff, considering what we were all going through then,

However, a review of 17 other studies [5] found that the use of Ivermectin was not associated with a reduction in COVID-19 viral clearance time, duration of hospitalization, mortality incidence or mechanical ventilation.

But here’s the part I know you are here for.

Potential Benefits of Ivermectin for Breast Cancer

Please be aware, first of all, that while there’s quite a bit of research on Ivermectin and its effects on cancer, most of the research is on cells and animals, not humans. Here’s what the research shows:

* Autophagy Inducer

A 2015 study [6] noted that Ivermectin induced autophagy in cancer cells. Autophagy is a cellular process whereby a cell breaks down and recycles its own damaged or unnecessary components – rather like a cellular recycling and waste removal system that helps maintain cell health and function. Autophagy in Greek literally means “self-eating”. This process usually doesn’t happen with cancer cells. In this way, Ivermectin starves tumors from within by forcing cancer cells to consume themselves beyond repair.

A 2016 study [7] also found that Ivermectin could induce autophagy in breast cancer cells which led to suppression of tumor growth, both in test tubes and in mice, as well as in breast tumors that had already been removed from patients.

* Tumor Suppressor

A 2015 study [8] found that Ivermectin had the ability to suppress tumor growth and restore tamoxifen sensitivity in triple negative breast cancer (TNBC) cells. This type of breast cancer seems to develop protective mechanisms to hide the tumor from cancer-killing T-cells.

* Immunomodulator

A protein receptor known as PD-1 (Programmed Cell Death Protein 1) is found on the surface of immune cells, particularly T cells, and it plays a vital role in regulating immune responses. It acts as an immune checkpoint, meaning it helps control the intensity of immune reactions and prevent them from becoming overactive and potentially harming the body’s own tissues. Drugs known as PD-1 inhibitors block this protein, preventing it from suppressing the immun system and allowing T cells to attack cancer cells. PD-1 inhibitors have significantly improved the progression of cancer in patients with PD-1+ metastatic TNBC when combined with chemotherapy.

Ivermectin and anti-PD-1 antibodies work synergistically, meaning their combined effect is greater than the sum of their individual effects. The combination of these two has shown promise in preclinical studies, with complete tumor regression observed in some cases. [9]

TNBC tumors are often called “cold” tumors because there are very few immune cells, limiting the efficacy of the PD-1 inhibitors described above. The study at [9] demonstrated that Ivermectin induces a robust infiltration of T-cells into breast tumors, thus turning “cold” tumors “hot” so that immune cells can “see” them and deal with them effectively.

* Mitochondrial Disruption

Cancer cells have high metabolic demands, requiring a constant supply of cellular energy in the form of ATP to fuel their rapid growth. A study on glioblastoma cells [10] showed that Ivermectin could inhibit mitochondrial complex I, an enzyme complex in the electron transport chain responsible for ATP production. This in effect reduces the availability of ATP, thus depriving cancer cells of the energy they need.

The depletion of ATP also acts as a stressor for cancer cells, triggering oxidative stress that damages the DNA, lipids and proteins. This “metabolic collapse” ultimately accelerates a normal cellular function that is absent in cancer cells called apoptosis – planned cell death. [11]

* Targets Cancer Stem Cells

One of the greatest challenges in cancer care are cancer stem cells, a powerful group of cells that can self-renew, resist treatment and drive cancer recurrence. They are often responsible for tumor regrowth after chemotherapy and radiotherapy – which are known to promote cancer stem cells and are quite often the reason women resist these treatments.

See my article Breast Cancer Stem Cells – Stopping Them In Their Tracks 

A 2018 study [12] found that Ivermectin inhibited cancer stem cells in TNBC and down-regulated (inhibited) the expression of genes associated with cancer stem cells.

A 2019 study [13] found that Ivermectin has the ability to target breast cancer stem cells. This study also showed that Ivermectin disrupted these aggressive cancer stem cells by down-regulating certain genes.

* Reverses Drug Resistance

A 2019 study [14] found that Ivermectin “drastically reversed the resistance of the tumor cells to the chemotherapeutic drugs both in vitro and in vivo.” It significantly enhanced the anti-cancer efficacy of chemotherapeutic drugs to tumor cells, especially drug-resistant cells.

By its many modes of anticancer action, Ivermectin may help to improve the effectiveness of therapies and reduce the likelihood of cancer recurrence.

While Ivermectin has been shown to directly kill cancer cells through the mechanisms discussed above, it also plays an indirect role in dismantling tumor defenses, tackling two of the greatest challenges in modern oncology: immune evasion and drug resistance.

Having said that, laboratory findings alone are not enough. We need rigorous clinical trials to be sure. Hopefully the scientific and medical communities will be willing to look beyond conventional treatment protocols and explore unconventional options.

Ongoing Clinical Trials on Ivermectin

I was able to find one clinical trial currently underway using Ivermectin for TNBC which looks promising.

NCT05318469: A phase I/II clinical trial, Cedars-Sinai Medical Center. This clinical trial is evaluating Ivermectin in combination with balstilimab (an anti-PD-1 checkpoint inhibitor) for metastatic TNBC. Expected to be completed October 2026. [15]

My Opinion

I am hopeful for Ivermectin with regard to its anti-breast cancer effects. The biggest problem is that Ivermectin is off-patent, meaning that there’s no financial incentive for pharmaceutical companies to fund large-scale clinical trials. So who is going to pay for that?

Most of the research has been carried out with cells and animal models, not actual humans. Ivermectin has not been approved by any governmental agencies for use in cancer.

Having said that, I do know a few women taking it along with standard therapies (and a couple who are using it with alternative medicine) and getting some good results. I feel that Ivermectin is promising because of the cell and animal studies which show it has numerous effects against cancer. It’s just that human clinical evidence isn’t strong yet.

If you’re curious about it, please talk with your integrative doctor and/or oncologist to see if it might be right for you. And check out what Ralph Moss has to say about it in this interview posted on his website: https://www.themossreport.com/s5-e2-ivermectin-and-cancer/

DISCLAIMER: Advice in this article should not be substituted for medical advice. Always seek the guidance of your doctor or other qualified health professional with any questions you may have regarding your health or a medical condition. Never disregard the advice of a medical professional, or delay in seeking it because of something you have read in this website.

References

[1] Over 25 Years of Clinical Experience With Ivermectin: An Overview of Safety for an Increasing Number of Indications – https://pubmed.ncbi.nlm.nih.gov/26954318/
[2] Ivermectin: A Multifaceted Drug With a Potential Beyond Anti-parasitic Therapy – https://www.cureus.com/articles/223832-ivermectin-a-multifaceted-drug-with-a-potential-beyond-anti-parasitic-therapy#!/
[3] The broad spectrum host-directed agent ivermectin as an antiviral for SARS-CoV-2 ? – https://www.sciencedirect.com/science/article/pii/S0006291X20319598?via%3Dihub
[4] The mechanisms of action of ivermectin against SARS-CoV-2—an extensive review – https://www.nature.com/articles/s41429-021-00491-6
[5] Efficacy and safety of ivermectin for the treatment of COVID-19: a systematic review and meta-analysis – https://academic.oup.com/qjmed/article/114/10/721/6375958?login=false
[6 ] Progress in Redirecting Antiparasitic Drugs for Cancer Treatment – https://www.dovepress.com/progress-in-redirecting-antiparasitic-drugs-for-cancer-treatment-peer-reviewed-fulltext-article-DDDT
[7] Ivermectin Induces Cytostatic Autophagy by Blocking the PAK1/Akt Axis in Breast Cancer – https://aacrjournals.org/cancerres/article/76/15/4457/613862/Ivermectin-Induces-Cytostatic-Autophagy-by
[8] Selective Inhibition of SIN3 Corepressor with Avermectins as a Novel Therapeutic Strategy in Triple-Negative Breast Cancer – https://aacrjournals.org/mct/article/14/8/1824/130583/Selective-Inhibition-of-SIN3-Corepressor-with
[9] Ivermectin converts cold tumors hot and synergizes with immune checkpoint blockade for treatment of breast cancer – https://www.biorxiv.org/content/10.1101/2020.08.21.261511v1.full
[10] Anthelmintic drug ivermectin inhibits angiogenesis, growth and survival of glioblastoma through inducing mitochondrial dysfunction and oxidative stress – https://www.sciencedirect.com/science/article/abs/pii/S0006291X16317429?via%3Dihub
[11] Antibiotic ivermectin preferentially targets renal cancer through inducing mitochondrial dysfunction and oxidative damage – https://www.sciencedirect.com/science/article/abs/pii/S0006291X1731656X?via%3Dihub
[12] Ivermectin as an inhibitor of cancer stem-like cells – https://pubmed.ncbi.nlm.nih.gov/29257278/
[13] The PAK1-Stat3 Signaling Pathway Activates IL-6 Gene Transcription and Human Breast Cancer Stem Cell Formation – https://www.mdpi.com/2072-6694/11/10/1527
[14] Ivermectin reverses the drug resistance in cancer cells through EGFR/ERK/Akt/NF-?B pathway – https://pmc.ncbi.nlm.nih.gov/articles/PMC6580523/
[15] Ivermectin and Balstilimab for the Treatment of Metastatic Triple Negative Breast Cancer – https://clinicaltrials.gov/study/NCT05318469?cond=Cancer&intr=Ivermectin&rank=1