What effect does ivermectin have on malignant diseases?

2026-09-15

The antitumour effects of ivermectin are currently studied primarily in preclinical (in vitro cell culture and animal model) investigations. In these laboratory experiments, ivermectin inhibited cell proliferation, enhanced apoptosis (programmed cell death), modulated signaling pathways (such as the PI3K/Akt/mTOR or Wnt/β-catenin pathways), and potentiated the efficacy of certain chemotherapeutic agents across several tumour types (for example, breast, lung, colorectal, gastric, bladder, and pancreatic cancer). Additionally, self-reports from cancer patients using a combination of ivermectin and mebendazole were assessed in a prospective observational study. Nevertheless, large-scale, randomised controlled human clinical trials have not yet confirmed its efficacy and safety in oncology, and unsupervised off-label use or the use of veterinary formulations can cause severe toxicity and organ damage. Early-phase clinical trials are ongoing, for example in metastatic triple-negative breast cancer in combination with immunotherapy (NCT05318469), as well as in solid tumours with immune checkpoint inhibitors (NCT07487805).

Numerous preclinical experiments have observed that ivermectin inhibits tumour cell proliferation and migration. In breast cancer cell lines, it reduced viability and invasion through the inhibition of the Wnt and PI3K/Akt/mTOR signaling pathways, as well as via the accumulation of reactive oxygen species (ROS). In non-small cell lung cancer and colorectal cancer models, it demonstrated synergy with recombinant methioninase or chemotherapeutic agents (e.g., cisplatin, paclitaxel). Growth inhibition of gastric cancer, bladder cancer, esophageal squamous cell carcinoma, and ovarian cancer cells has also been described in further in vitro and rodent models.

Although in a 197-patient prospective observational cohort—where patients received ivermectin and mebendazole via telemedicine alongside other therapies—the majority of respondents reported subjective clinical benefit, the oncological literature emphasizes the lack of human clinical evidence. Case reports highlight the risks of unmonitored use driven by internet disinformation, including life-threatening neurotoxicity, drug-induced liver injury (DILI), and other severe symptoms of intoxication.

References

  1. Real-world Clinical Outcomes of Ivermectin and Mebendazole in Cancer Patients: Results from a Prospective Observational Cohort. PMID 42203321
  2. Life-threatening neurotoxicity following off-label ivermectin use in metastatic breast cancer: a case report. PMID 42170801
  3. Tumor growth suppression of ivermectin in gastric cancer cell lines and primary gastric cancer organoids. PMID 42434256
  4. Drug-Induced Liver Injury Following Co-ingestion of Veterinary Fenbendazole and Ivermectin for Prostate Cancer: A Case Report. PMID 42299164
  5. Combination of ivermectin and metformin promotes autophagy in MCF‑7 cells by inhibiting phosphorylation of the PI3K/AKT/mTOR pathway. PMID 42138203
  6. Selective Synergy of the Combination of Recombinant Methioninase With Cisplatinum and Ivermectin Which Eradicates Lung-Cancer Cells but Has No Synergy and Limited Effect on Normal Fibroblasts. PMID 41318162
  7. Ivermectin inhibits ER, HER2, and TGF-β pathways in ER-positive and endocrine-resistant breast cancer cells. PMID 42060658
  8. Ivermectin as an Alternative Anticancer Agent: A Review of Its Chemical Properties and Therapeutic Potential. PMID 41155573
  9. Ivermectin and gynecologic cancer: What's the data? PMID 40851910
  10. Ivermectin in Cancer Treatment: Should Healthcare Providers Caution or Explore Its Therapeutic Potential? PMID 40715995
  11. Ivermectin inhibits the growth of ESCC by activating the ATF4-mediated endoplasmic reticulum stress-autophagy pathway. PMID 39574166
  12. Ivermectin Inhibits Bladder Cancer Cell Growth and Induces Oxidative Stress and DNA Damage. PMID 38375808
  13. Ivermectin in Combination With Balstilimab or Pembrolizumab in Patients With Metastatic Triple Negative Breast Cancer NCT05318469
  14. Ivermectin Combined With Immune Checkpoint Inhibition in Cancer (ICONIC) NCT07487805

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