Glioblastoma is the most aggressive and lethal primary brain tumor in adults, characterized by rapid growth, diffuse invasion of surrounding brain tissue, and profound resistance to therapy. Even with maximal surgical resection followed by radiation and chemotherapy, median survival typically remains little more than one year. One of the major challenges in treating glioblastoma is the blood–brain barrier, which prevents many potentially effective drugs from reaching tumor tissue at therapeutic concentrations. For this reason, there has been increasing interest in drug repurposing—identifying already approved medications with favorable safety profiles that can cross the blood–brain barrier and target cancer-specific vulnerabilities.

A notable preclinical study published on PubMed Central (PMC3158014) investigated the anti-tumor potential of mebendazole, an FDA-approved antiparasitic drug widely used for decades to treat intestinal worm infections. The researchers tested mebendazole in multiple mouse models of glioblastoma to evaluate its effects on tumor growth and survival. Their findings provided strong evidence that mebendazole possesses significant anti-glioblastoma activity under experimental conditions.

Mechanistically, mebendazole was shown to disrupt microtubule formation in cancer cells. Microtubules are essential components of the cell’s internal scaffolding and are critical for cell division. By interfering with microtubule polymerization, mebendazole effectively inhibits tumor cell proliferation, a mechanism similar to that of established chemotherapeutic agents such as vinca alkaloids. However, a key advantage of mebendazole is its comparatively low toxicity, as demonstrated by its long-standing clinical use in humans for non-cancer indications.

One of the most important findings of the study was mebendazole’s ability to cross the blood–brain barrier. This property is a major limitation for many anticancer drugs and represents a significant obstacle in brain tumor therapy. Oral administration of mebendazole resulted in sufficient drug levels within brain tissue to exert anti-tumor effects, confirming its potential relevance for central nervous system malignancies.

In terms of therapeutic outcomes, mebendazole treatment significantly slowed glioblastoma tumor growth in mice. More importantly, treated animals demonstrated a marked survival advantage compared with untreated controls. In a disease where progression is typically measured in weeks, the extension of survival by several weeks represents a substantial benefit in preclinical terms. These findings suggest that mebendazole did not merely delay tumor growth temporarily but meaningfully altered disease trajectory in aggressive glioblastoma models.

The study also examined combination therapy, which is particularly relevant given the complexity and adaptability of glioblastoma. When mebendazole was combined with temozolomide—the current standard chemotherapy for brain cancer—survival outcomes improved further. In some experimental models, approximately 70% of mice receiving the combination therapy survived, compared with around 40% survival in mice treated with temozolomide alone. This additive or synergistic effect indicates that mebendazole may enhance the efficacy of existing treatments rather than competing with them, an important consideration for clinical translation.

Despite these promising findings, the authors emphasized that the results are strictly preclinical. Mouse models, while valuable, cannot fully replicate the biological complexity of human glioblastoma, which exhibits extensive genetic heterogeneity and interacts dynamically with the human immune system. Optimal dosing, long-term safety in cancer patients, and effectiveness across different molecular subtypes of glioblastoma remain unresolved questions. Therefore, the study does not position mebendazole as a cure, but rather as a strong candidate for further investigation.

In conclusion, the preclinical study published on PubMed Central demonstrates that mebendazole significantly slows glioblastoma growth, crosses the blood–brain barrier, extends survival in animal models, and enhances the effectiveness of standard chemotherapy (PubMed Central, PMC3158014). Given its low cost, established safety profile, and ability to target cancer cell division with relatively low toxicity, mebendazole represents a promising drug-repurposing candidate. These findings provide a strong rationale for controlled clinical trials to determine whether the benefits observed in animal models can translate into improved outcomes for patients with glioblastoma.