Fenbendazole Enhancing Anti-Tumor Effect: A Case Series

Abstract Background: Fenbendazole (FBZ) is a cheap and readily available anti-parasitic commonly used in veterinary medicine. FBZ belongs to the benzimidazole drug class which destabilize microtubules through a mechanism similar to the anti-oncogenic vinca alkaloids. Although there are no reported cases in the literature, there have been several anecdotal stories published on website blogs with individuals praising its ability to treat a wide variety of cancers. Case Presentations: Herein we describe the cases of three patients with various genitourinary malignancies who demonstrated complete response after receiving FBZ therapy as a single or supplementary chemotherapeutic agent. In two patient scenarios, they had experienced progression of metastatic disease despite multiple lines of therapy prior to initiation of FBZ. No side effects from FBZ were reported. Conclusion: FBZ appears to be a potentially safe and effective antineoplastic agent that can be repurposed for human use in treating genitourinary malignancies. Further research is necessary to define the role of FBZ as a chemotherapeutic option.