Scientists have identified a potential new use for Viagra’s active ingredient, sildenafil, after finding that it may interfere with the ability of cancer cells to spread to other parts of the body.
The findings, published in the peer-reviewed journal Cancer Research on July 14, 2026, show that sildenafil disrupted cholesterol trafficking inside cancer cells, reducing the availability of cholesterol needed for cell movement and metastasis.
Researchers led by Yarden Ariav in Professor Ayelet Erez’s laboratory at the Weizmann Institute of Science studied the drug across multiple mouse cancer models and human cancer-cell systems. They found that sildenafil, a PDE5 inhibitor, increased levels of cGMP, which interfered with NPC1, a protein responsible for moving cholesterol out of lysosomes.
This caused cholesterol to accumulate inside lysosomes while reducing the amount available elsewhere in the cancer cell. The resulting shortage disrupted cellular structures and energy processes involved in cancer-cell movement, limiting migration and metastatic spread in the experimental models.
The researchers also examined health records from Clalit Health Services. Their analysis found significantly better survival among cancer patients who had used sildenafil, with an additional benefit observed among those who had also taken statins, which are commonly prescribed to lower cholesterol.
The combination appears to work through two different mechanisms: sildenafil interferes with cholesterol transport inside cells, while statins reduce the production of new cholesterol. The researchers reported that the combination produced additive anti-metastatic effects in their experiments.
However, the findings do not mean Viagra has been established as a cancer treatment. The experimental evidence came from mouse models and human cancer-cell systems, while the patient data were observational health-record data. Further clinical research would be needed to determine whether sildenafil can safely and effectively prevent or treat cancer metastasis in patients.
The study was authored by researchers from the US National Cancer Institute among other partners.
