Fenbendazole

Where it participates (unsigned role)

1. In glioblastoma cell lines mebendazole displayed cytotoxicity with half-maximal inhibitory concentrations ranging from 0.1 to 0.3 micromolar, disrupted microtubule formation in those cells with in vitro activity correlated with reduced tubulin polymerization, and significantly extended mean survival by up to 63% in syngeneic and xenograft orthotopic mouse glioma models; the programme began with the serendipitous observation that fenbendazole, used to treat pinworm infection, inhibited brain tumour engraftment.

   Mebendazole → Viability of glioblastoma cells source_derived_draftungraded
   Experimental context and source evidence

   evidence_span

   {"source_cache": "artifacts/mebendazole-research/21764822.abstract.txt", "locator": "Indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "31b328d5c2340f7a4e9b6a3b3d46c68a8c0265c50d483375bc6dc15bb1696ad6", "start_char": 0, "end_char": 1210, "text_sha256": "31b328d5c2340f7a4e9b6a3b3d46c68a8c0265c50d483375bc6dc15bb1696ad6"}

   experimental_model

   Cell line cytotoxicity, tubulin polymerisation and syngeneic and xenograft orthotopic mouse glioma models

   exposure

   Mebendazole compared with fenbendazole, at doses documented as safe in humans

   limitations

   The observation that started the programme was serendipitous, from pinworm treatment of laboratory animals. Mouse models, and the survival gain is a mean rather than a cure.

   nutrient_topic

   Mebendazole research collection; topical membership is not evidence of a direct clinical effect, and mebendazole is recorded separately from albendazole, from the benzimidazole class and from its own crystal forms. · Mebendazole

   organism

   Human cells and mouse

   plain_language

   The worm drug killed brain tumour cells at low concentrations and let mice live substantially longer.

   primary_references

   [mbz-p21764822] Antiparasitic mebendazole shows survival benefit in 2 preclinical models of glioblastoma multiforme. (2011). https://pubmed.ncbi.nlm.nih.gov/21764822/ DOI: 10.1093/neuonc/nor077

   tissue_or_cell_type

   Glioblastoma

   Mebendazole: the tubulin it binds, why that is selective, the crystal form that decides whether any of it works, and the off-target that became an oncology programme (2026-09-22) · lines 485–496

   AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Cell line cytotoxicity, tubulin polymerisation and syngeneic and xenograft orthotopic mouse glioma models · source_derived_draft · unverified_draft

   ### mbz-glioma-cytotoxicity In glioblastoma cell lines mebendazole displayed cytotoxicity with half-maximal inhibitory concentrations ranging from 0.1 to 0.3 micromolar, disrupted microtubule formation in those cells with in vitro activity correlated with reduced tubulin polymerization, and significantly extended mean survival by up to 63% in syngeneic and xenograft orthotopic mouse glioma models; the programme began with the serendipitous observation that fenbendazole, used to treat pinworm infection, inhibited brain tumour engraftment. Condition category: normal nutrient_topic: Mebendazole research collection; topical membership is not evidence of a direct clinical effect, and mebendazole is recorded separately from albendazole, from the benzimidazole class and from its own crystal forms. plain_language: The worm drug killed brain tumour cells at low concentrations and let mice live substantially longer. organism: Human cells and mouse tissue_or_cell_type: Glioblastoma experimental_model: Cell line cytotoxicity, tubulin polymerisation and syngeneic and xenograft orthotopic mouse glioma models limitations: The observation that started the programme was serendipitous, from pinworm treatment of laboratory animals. Mouse models, and the survival gain is a mean rather than a cure. exposure: Mebendazole compared with fenbendazole, at doses documented as safe in humans evidence_span: {"source_cache": "artifacts/mebendazole-research/21764822.abstract.txt", "locator": "Indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "31b328d5c2340f7a4e9b6a3b3d46c68a8c0265c50d483375bc6dc15bb1696ad6", "start_char": 0, "end_char": 1210, "text_sha256": "31b328d5c2340f7a4e9b6a3b3d46c68a8c0265c50d483375bc6dc15bb1696ad6"} [mbz-p21764822] Antiparasitic mebendazole shows survival benefit in 2 preclinical models of glioblastoma multiforme. (2011). https://pubmed.ncbi.nlm.nih.gov/21764822/ DOI: 10.1093/neuonc/nor077

   Complete structured claim and evidence

2. Median inhibitory concentrations for nocodazole, oxibendazole, parbendazole, mebendazole and fenbendazole against bovine brain tubulin polymerisation ranged from 1.97 x 10-6 to 6.32 x 10-6 molar, while benomyl, cambendazole and carbendazim had values from 5.83 x 10-5 to 9.01 x 10-5 molar and thiabendazole had a value of 5.49 x 10-4 molar.

   Mebendazole → Polymerisation of tubulin into microtubules source_derived_draftungraded
   Experimental context and source evidence

   evidence_span

   {"source_cache": "artifacts/mebendazole-research/728472.abstract.txt", "locator": "Indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "544c36409218c93ebff76d932a2bc6e14ccf7fd6e217d4614c4b561281c2555a", "start_char": 0, "end_char": 1025, "text_sha256": "544c36409218c93ebff76d932a2bc6e14ccf7fd6e217d4614c4b561281c2555a"}

   experimental_model

   Turbidimetric microtubule polymerisation assay and colchicine binding assay on purified bovine brain tubulin

   exposure

   Eleven benzimidazoles compared for inhibition of the initial rate of microtubule polymerisation

   limitations

   Purified mammalian tubulin, which is the off-target rather than the parasite target. It fixes where mebendazole sits in the class by potency.

   nutrient_topic

   Mebendazole research collection; topical membership is not evidence of a direct clinical effect, and mebendazole is recorded separately from albendazole, from the benzimidazole class and from its own crystal forms. · Mebendazole

   organism

   Cattle

   plain_language

   Mebendazole sits in the potent group; thiabendazole is about a hundred times weaker.

   primary_references

   [mbz-p728472] Interaction of anthelmintic benzimidazoles and benzimidazole derivatives with bovine brain tubulin. (1978). https://pubmed.ncbi.nlm.nih.gov/728472/ DOI: 10.1016/0304-4165(78)90334-3

   tissue_or_cell_type

   Brain tubulin

   Mebendazole: the tubulin it binds, why that is selective, the crystal form that decides whether any of it works, and the off-target that became an oncology programme (2026-09-22) · lines 82–93

   AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Turbidimetric microtubule polymerisation assay and colchicine binding assay on purified bovine brain tubulin · source_derived_draft · unverified_draft

   ### mbz-inhibits-polymerisation Median inhibitory concentrations for nocodazole, oxibendazole, parbendazole, mebendazole and fenbendazole against bovine brain tubulin polymerisation ranged from 1.97 x 10-6 to 6.32 x 10-6 molar, while benomyl, cambendazole and carbendazim had values from 5.83 x 10-5 to 9.01 x 10-5 molar and thiabendazole had a value of 5.49 x 10-4 molar. Condition category: normal nutrient_topic: Mebendazole research collection; topical membership is not evidence of a direct clinical effect, and mebendazole is recorded separately from albendazole, from the benzimidazole class and from its own crystal forms. plain_language: Mebendazole sits in the potent group; thiabendazole is about a hundred times weaker. organism: Cattle tissue_or_cell_type: Brain tubulin experimental_model: Turbidimetric microtubule polymerisation assay and colchicine binding assay on purified bovine brain tubulin limitations: Purified mammalian tubulin, which is the off-target rather than the parasite target. It fixes where mebendazole sits in the class by potency. exposure: Eleven benzimidazoles compared for inhibition of the initial rate of microtubule polymerisation evidence_span: {"source_cache": "artifacts/mebendazole-research/728472.abstract.txt", "locator": "Indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "544c36409218c93ebff76d932a2bc6e14ccf7fd6e217d4614c4b561281c2555a", "start_char": 0, "end_char": 1025, "text_sha256": "544c36409218c93ebff76d932a2bc6e14ccf7fd6e217d4614c4b561281c2555a"} [mbz-p728472] Interaction of anthelmintic benzimidazoles and benzimidazole derivatives with bovine brain tubulin. (1978). https://pubmed.ncbi.nlm.nih.gov/728472/ DOI: 10.1016/0304-4165(78)90334-3

   Complete structured claim and evidence

3. The inhibition constants of mebendazole and fenbendazole for Ascaris suum embryonic tubulin were 1.9 x 10-8 and 6.5 x 10-8 molar while those for bovine brain tubulin were 7.3 x 10-6 and 1.7 x 10-5 molar, values 250 to 400 times greater, so that differential binding affinities between nematode and mammalian tubulin may explain the selective toxicity.

   Mebendazole → Nematode beta-tubulin source_derived_draftungraded
   Experimental context and source evidence

   evidence_span

   {"source_cache": "artifacts/mebendazole-research/7388055.abstract.txt", "locator": "Indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "5613d7fb281b4fd39b17bfdbafaf0ea823fb63b928048a9dd112fb71bf4cd2b7", "start_char": 0, "end_char": 1209, "text_sha256": "5613d7fb281b4fd39b17bfdbafaf0ea823fb63b928048a9dd112fb71bf4cd2b7"}

   experimental_model

   Inhibition of tritiated colchicine binding to cytosolic tubulin from 8-day Ascaris suum embryos and from bovine brain

   exposure

   Mebendazole and fenbendazole compared on the two tubulins in the same assay

   limitations

   The founding selectivity result. It measures embryonic tubulin; the study in this collection that measured intestinal tubulin found a far smaller difference.

   nutrient_topic

   Mebendazole research collection; topical membership is not evidence of a direct clinical effect, and mebendazole is recorded separately from albendazole, from the benzimidazole class and from its own crystal forms. · Mebendazole

   organism

   Nematode and cattle

   plain_language

   The drug grips worm tubulin hundreds of times more tightly than ours, which is the usual explanation for why it is safe.

   primary_references

   [mbz-p7388055] Interaction of anthelmintic benzimidazoles with Ascaris suum embryonic tubulin. (1980). https://pubmed.ncbi.nlm.nih.gov/7388055/ DOI: 10.1016/0304-4165(80)90431-6

   tissue_or_cell_type

   Embryonic nematode tubulin and bovine brain tubulin

   Mebendazole: the tubulin it binds, why that is selective, the crystal form that decides whether any of it works, and the off-target that became an oncology programme (2026-09-22) · lines 95–106

   AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Inhibition of tritiated colchicine binding to cytosolic tubulin from 8-day Ascaris suum embryos and from bovine brain · source_derived_draft · unverified_draft

   ### mbz-selectivity-250-fold The inhibition constants of mebendazole and fenbendazole for Ascaris suum embryonic tubulin were 1.9 x 10-8 and 6.5 x 10-8 molar while those for bovine brain tubulin were 7.3 x 10-6 and 1.7 x 10-5 molar, values 250 to 400 times greater, so that differential binding affinities between nematode and mammalian tubulin may explain the selective toxicity. Condition category: normal nutrient_topic: Mebendazole research collection; topical membership is not evidence of a direct clinical effect, and mebendazole is recorded separately from albendazole, from the benzimidazole class and from its own crystal forms. plain_language: The drug grips worm tubulin hundreds of times more tightly than ours, which is the usual explanation for why it is safe. organism: Nematode and cattle tissue_or_cell_type: Embryonic nematode tubulin and bovine brain tubulin experimental_model: Inhibition of tritiated colchicine binding to cytosolic tubulin from 8-day Ascaris suum embryos and from bovine brain limitations: The founding selectivity result. It measures embryonic tubulin; the study in this collection that measured intestinal tubulin found a far smaller difference. exposure: Mebendazole and fenbendazole compared on the two tubulins in the same assay evidence_span: {"source_cache": "artifacts/mebendazole-research/7388055.abstract.txt", "locator": "Indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "5613d7fb281b4fd39b17bfdbafaf0ea823fb63b928048a9dd112fb71bf4cd2b7", "start_char": 0, "end_char": 1209, "text_sha256": "5613d7fb281b4fd39b17bfdbafaf0ea823fb63b928048a9dd112fb71bf4cd2b7"} [mbz-p7388055] Interaction of anthelmintic benzimidazoles with Ascaris suum embryonic tubulin. (1980). https://pubmed.ncbi.nlm.nih.gov/7388055/ DOI: 10.1016/0304-4165(80)90431-6

   Complete structured claim and evidence