Fenben lab fenbendazole (methyl N-(6-phenylsulfanyl-1H-benzimidazol-2-yl) carbamate), is a broad-spectrum, relatively safe, anthelmintic that is used to treat ascarid and hookworm infections in domestic animals. It acts on helminthes by binding to tubulin and disrupting the microtubule equilibrium, thereby inhibiting polymerization in the parasites. The benzimidazole family of drugs also has antitumor properties.
Recently, a patient with metastatic colorectal cancer was treated with pembrolizumab in combination with fenbendazole. Her CEA level increased, and she reported worsening pain and a low appetite. She was referred for palliative care at McMaster University. Upon physical exam, the patient was afebrile and febrile, but otherwise healthy. Her past medical history was unremarkable.
In a mouse model of allergic airway disease induced by ovalbumin exposure, fenbendazole treatment decreased Th2-derived cytokines and goblet cell numbers in lung sections. In addition, bronchoalveolar lavage fluid eosinophil counts were significantly lower in the fenbendazole group than in the control group.
In a separate study, an unreported number of SCID mice were fed diets supplemented with either fenbendazole or mebendazole for 2 wk before subcutaneous flank implantation of 3 x 107 human lymphoma cells. Tumor growth was evaluated at 4-d intervals until tumors reached a calculated volume of 1500 mm3. Although both diets significantly reduced tumor growth, the combined diets had a synergistic effect, and the dose of fenbendazole required to achieve this effect is less than that needed for effective anthelmintic treatment of pinworm infestations in cats. Vitamin concentrations in prepared diets deteriorate with time, and the study diet was nearing expiration (6 mo after manufacture) at the beginning of this experiment. fenben lab fenbendazol