Which Repurposed Drugs Are Effective in Treating Cancer?

Summary of the anti-cancer pathways of the repurposed drugs and nutraceuticals

Some drugs that were originally made for other health issues are now being used to treat cancer. Here are a few examples:

> Mebendazole: Originally used to treat parasites, this drug has shown promise in treating brain tumors and other cancers. A wide variety of cancers, including NSCLC (non small cell lung cancer), adrenocortical, colorectal, chemo-resistant melanoma, glioblastoma multiforme, colon, leukemia, osteosarcoma/soft tissue sarcoma, acute myeloid sarcoma, breast (ER+ invasive ductal), kidney, and ovarian carcinoma, have been shown to be responsive to benzimidazoles, including MBZ (Guerini 2019, Meco 2023). First-in-the-World Ivermectin, Mebendazole and Fenbendazole Protocol in Cancer has been peer-reviewed and published on Sep.19, 2024 in the Journal of Orthomolecular Medicine. Co-authors include Dr Paul Marik and Dr William Makis: Targeting the Mitochondrial-Stem Cell Connection in Cancer Treatment: A Hybrid Orthomolecular Protocol.

> Fenbendazole: Fenbendazole is a broad spectrum anthelmintic used against gastrointestinal parasites. One study found unexpected tumor growth inhibition in a group of mice treated with a combination of Fenbendazole and vitamins. As more studies emerge – some already published, some currently ongoing – a rapidly growing number of human patients are taking Fenbendazole to treat their cancer. The Fenbendazole Cancer Protocol has been gaining rapid interest over the past years following some fenbendazole advanced cancer success stories. Joe Tippens founded the protocol after he was told a story about a scientist at Merck Animal Health that had been performing cancer research on mice. The research included injecting different types of cancers into different mice body parts. The scientists discovered, through trial and error, a product in their canine product line, fenbendazole, that was batting 1.000 in killing these different cancers in the mice. The scientist was later diagnosed with stage 4 brain cancer and was given a grim prognosis of only three months to live. She decided to try the fenbendazole, and after six weeks, showed a clean scan. Joe Tippens had been initially diagnosed with small cell lung cancer. The cancer later spread to his neck, right lung, stomach, liver, bladder, pancreas and tail bone. Like the scientist from Merck Animal Hospital, Joe was told he only had three months to live. In 2017, after hearing the story of the scientist who treated her cancer with a canine drug, Joe decided he was going to do the same. However, in addition to taking the fenbendazole, Joe added his own ingredients to the regimen (curcumin, vitamin E and CBD oil), thus creating the Joe Tippens Cancer Protocol.

> Ivermectin: In a 2021 review paper, the related mechanisms by which ivermectin inhibited the development of different cancers and promoted programmed cell death were discussed. Also reviewed was the prospects for the clinical application of ivermectin as an anticancer drug for cancer therapy. In another study, published in Nature (2021), Ivermectin stimulates T-cells to invade and destroy tumors and synergizes with immune checkpoint blockade for treatment of breast cancer.

> Metformin: A diabetes drug that is now being studied for its potential to fight cancers like breast and pancreatic cancer. A 2023 meta-analysis revealed a 45% risk reduction in thyroid cancer among metformin users in Eastern countries, a phenomenon which was more evident in Asian populations than their Western counterparts. Another extensive 2022 meta-analysis ascertained a notably lower gynecological cancer occurrence in those undergoing metformin treatment compared to alternative therapies (gynecological cancer: HR = 0.60, 95% CI: 0.49–0.74; endometrial cancer: HR = 0.65, 95% CI: 0.50–0.85; ovarian cancer: HR = 0.47, 95% CI: 0.27–0.82).

> Aspirin: A common pain reliever that might help prevent colorectal cancer. In November 2023, researchers from Cardiff University in the United Kingdom published a comprehensive review in the British Journal of Cancer (BJC) outlining aspirin’s potential to reduce cancer mortality, prevent metastatic cancer spread, and minimize vascular complications. The review encompassed both favorable and unfavorable evidence, thoroughly analyzing the rationale behind using aspirin in cancer treatment. The study compiled results from 118 observational studies involving approximately 1 million cancer patients. It revealed that daily intake of low-dose aspirin (75 or 81 milligrams) was associated with a 21 percent reduction in all-cause mortality.

> Statins: Drugs that lower cholesterol, which may also help in preventing or treating some types of cancer. Statins lower circulating blood lipids including low-density lipoprotein (LDL) cholesterol through the competitive inhibition of 3-hydroxy-3-methyl-glutaryl-coenzyme A reductase (HMGCR), an enzyme that facilitates the conversion of HMG-CoA to mevalonic acid, which is a crucial step in cholesterol biosynthesis. By inhibiting this process, statins not only reduce cholesterol production but also impact by-products essential for cancer cell growth, thereby demonstrating their potential as anticancer agents (source). Of the statins, simvastatin is particularly interesting due to its anticancer applications, which have been observed in various cancer types and are largely mediated through activation of mutant P53. 

> Propranolol: A drug for high blood pressure that has shown effectiveness in treating certain cancers, like angiosarcoma.

> Thalidomide: Originally a sedative, it was repurposed and approved in 1998 to treat multiple myeloma, a type of cancer.

> Arsenic Trioxide: Once used as a poison, it was repurposed and approved in 2000 to treat a type of leukemia (a blood cancer).

These drugs have been repurposed to help treat or prevent cancer. While some are already approved for this use, others are still being studied. Their effectiveness can vary depending on the type of cancer and the individual patient.

Sources:

https://www.onedaymd.com/2023/06/top-10-metabolic-interventions-to.html

Ivermectin Cancer Success Stories: Case Series (2025)

Fenbendazole Cancer Success Stories and Treatment Testimonials: Case Series.

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