Mebendazole is a broad-spectrum benzimidazole and anti-helminthic used as a treatment for roundworms. More recently it has been investigated as an anti-cancer agent, showing promise in vitro and in mouse models.
Benzimidazoles are heterocyclic and aromatic organic compounds. They are bicyclic compounds formed by the fusion of benzene and imidazole ring systems, which are essential pharmacophores and privileged structures in medicinal chemistry. Variations in the position of the benzimidazole ring can be used to develop target-specific derivatives. Mebendazole is the combination of benzoyl + carbamate.
Mebendazole came into use in 1971, after it was developed by Janssen Pharmaceutica in Belgium
Mebendazole is soluble in formic acid but is practically insoluble in water, ethanol, and ether.
| Mechanism of Action |
Mebendazole inhibits tubulin polymerization. Specifically, it binds to the colchicine binding site of beta-tubulin, thus blocking the polymerization of tubulin dimers in the intestinal cells of the parasite. The lack of transportation in the cell causes a build-up of waste and a depletion of energy. In cancer, Mebendazole can regulate tumor angiogenesis, autophagy, apoptosis, modulation of key signaling pathways, boost antitumor immune responses, and inhibiti matrix metalloproteinases activity (Aliabadi et al, 2025). |
| Spectrum | Parasites including roundworms, threadworms, tapeworms, pinworms, and other nematode and trematodes. |
| Cancer Applications |
Mebendazole induced a dose- and time-dependant apoptotic response that was dose and time dependant, in a range of lung cancer cell lines (IC50 ~0.16 μM). Cells were arrested in the G2-M phase before the beginning of apoptosis. Mebendazole had no effect on normal HUVECs or WI38 fibroblasts, even at 1 μM. In vitro results showed it inhibited lung cancer cell growth 5-fold compared to controls. Growth inhibitory effects of MBZ against breast, ovary, colon carcinomas, and osteosarcoma were seen (IC50s 0.1 - 0.8 μM) (Mukhopadhyay T et al (2002). In vitro activity of Mebendazole against chemoresistant melanoma cell lines was assessed. A screening of 2000 small molecules against melanoma cells was conducted and ten compounds with inhibitory action against M-14 and SK-Mel-19 chemoresistant melanoma cells lines were chosen, that were also non-toxic to normal melanocytes. Of these ten compounds, four were benzimidazoles (Mebendazole, albendazole, fenbendazole, and oxybendazole) and Mebendazole was selected for further review. It induced dose-dependent apoptosis in both cell lines with an average IC50 of 0.32 μM, while the equivalent for the non-cancerous melanocyte cell line was IC50 of 1.9 μM. Mebendazole had the greatest inhibitory effect against the melanoma cells of the four benzimidazoles tested (2008). Despite the promising findings on MBZ oncology repositioning, some challenges and limitations remain, including poor solubility and a slow disintegrating rate, which results in lower bioavailability. Furthermore, the variety of resistance mechanisms and variability in response to different tumor types, due to differences in genetic profiles, tumor microenvironments, and drug metabolism between patients, are all factors to consider for clinical cancer applications. |
| Impurity Profile | Total Impurities: Not more than 1.0% Impurity A: Not more than 0.25% Impurity B: Not more than 0.25% Impurity C: Not more than 0.25% Impurity D: Not more than 0.25% Impurity E: Not more than 0.25% Impurity F: Not more than 0.25% Impurity G: Not more than 0.50% |
| Molecular Formula | C16H13N3O3 |
| References |
Aliabadi A, Moradi SZ, Abdian S, Fakhri S and Echeverría J (2025) Critical dysregulated signaling pathways in drug resistance: highlighting the repositioning of mebendazole for cancer therapy. Front. Pharmacol. 16:1631419 Doudican N et al (2008). Mebendazole induces apoptosis via Bcl-2 inactivation in chemoresistant melanoma cells. Mol. Cancer Res. 6(8):1308-1315 PMID 18667591 Mukhopadhyay T et al (2002) Mebendazole elicits a potent antitumor effect on human cancer cell lines both in vitro and in vivo. Clin. Cancer Res.8(9) 2963–2969 PMID 12231542 Pantziarka P, Bouche G, Meheus L, Sukhatme V and Sukhatme VP (2014). Repurposing drugs in oncology (ReDO)—Mebendazole as an anti-cancer agent. ecancer 8:443doi.org/10.3332 Vercruysse J and Claerebout E (2014) Mechanisms of action of anthelmintics. Merck Veterinary Manual. Merck & Co., In |