A US patent for a potential breakthrough cancer treatment is drawing renewed attention after declassified CIA documents revealed how scientists may have been close to a cure 60 years ago.
The patent, published by Johns Hopkins University in 2021 and titled ‘Mebendazole Polymorph for Treatment and Prevention of Tumors,’ outlines how specific formulations of the drug mebendazole may be used to target cancer cells.
Mebendazole has been used safely for more than four decades to treat parasitic worm infections in humans, but researchers have increasingly investigated whether the drug could also help fight certain cancers, including aggressive brain tumors.
According to the patent, a specific crystalline form of the drug known as polymorph C may be more effective than other versions because it is absorbed more efficiently by the body.
The patent also notes that laboratory studies showed the drug reduced tumor growth and helped mice with brain tumors live longer, prompting early clinical trials to test whether the treatment is safe and effective in humans.
However, the filing has sparked intense reactions online, with some commentators claiming the discovery raises questions about how widely such treatments have been explored.
One widely circulated social media post claimed: ‘Johns Hopkins Hospital has had the patent for Mebendazole Polymorph for the treatment and prevention of tumors for a long time. This was suppressed because the cancer industry makes $225 billion a year on designer drugs.’
The outrage follows a declassified 1951 CIA report circulated online describing Soviet research that found similarities between parasitic worms and cancer cells and suggested some anti-parasitic drugs could disrupt tumor growth.
A US patent describing a potential cancer treatment is drawing renewed attention after a Cold War–era CIA document resurfaced online describing similar research more than 60 years ago
The patent itself focuses on how the long-standing anti-parasitic medication might be repurposed as a cancer therapy, particularly for tumors that are difficult to treat with conventional drugs.
Mebendazole belongs to a class of medicines known as benzimidazoles, which are commonly used to kill parasitic worms by interfering with their ability to absorb nutrients.
The drug has been widely prescribed around the world for infections such as pinworm, whipworm, and other intestinal parasites.
Over the past decade, however, researchers have begun studying whether the same biological mechanisms that make the drug lethal to parasites might also affect cancer cells.
According to the patent, one of the key findings involves the drug’s crystal structure, known as a polymorph.
Pharmaceutical compounds can exist in several different solid forms, and each form can behave differently in the body depending on how easily it dissolves and is absorbed.
The researchers identified polymorph C as the most promising version for cancer treatment.
The patent states that formulations containing at least 90 percent polymorph C appear to deliver the drug more effectively than other versions, allowing higher levels of the compound to circulate in the body.
The patent, published by Johns Hopkins University in 2021 and titled ‘Mebendazole Polymorph for Treatment and Prevention of Tumors,’ outlines how specific formulations of the drug mebendazole may be used to target cancer cells
Scientists believe this improved absorption may help the drug reach tumors more efficiently, potentially slowing or stopping their growth.
Another challenge the researchers sought to address is the blood-brain barrier, a protective network of cells that prevents many drugs from entering brain tissue.
While this barrier protects the brain from harmful substances, it also makes brain cancers notoriously difficult to treat because most medicines cannot penetrate it.
The patent suggests that formulations of mebendazole could be combined with other medications that help drugs cross this barrier, increasing the chances that the treatment could reach tumors located in the brain.
Laboratory experiments described in the patent found that mice with brain tumors treated with the drug experienced significantly reduced tumor growth and longer survival times compared with untreated animals.
Researchers believe the drug may attack cancer through several biological pathways, including interfering with proteins that cancer cells rely on to divide, reducing the formation of new blood vessels that feed tumors, and triggering apoptosis, a process that causes damaged or abnormal cells to self-destruct.
The patent also notes that the treatment could potentially be used not only to treat tumors but also to help prevent cancer in people who are at elevated risk, including individuals with certain genetic conditions or family histories linked to colorectal cancer.
The image shows two mice genetically prone to developing pancreatic cancer. The untreated mouse developed tumors (LEFT), while the mouse that was given the drug mebendazole in its diet showed little or no signs of cancer.
In addition to brain tumors, the researchers suggest the drug could potentially be studied as a therapy for a wide range of cancers, including those affecting the breast, lung, pancreas, colon, liver, prostate and blood.
Interest in the patent has grown in recent days after a decades-old intelligence document began circulating widely online.
The two-page CIA report, produced in February 1951 and declassified in 2014, summarizes a Soviet scientific paper that examined similarities between parasitic worms and cancerous tumors.
According to the document, researchers observed that both parasites and malignant tumors appeared to thrive under similar metabolic conditions and stored large reserves of glycogen, a form of energy used by living cells.
The report also described experiments showing that certain chemical compounds were capable of affecting both parasitic infections and malignant tumors.
One drug highlighted in the document, known as Myracyl D, was reportedly effective against bilharzia parasites as well as cancerous growths in experimental studies.
Other compounds mentioned in the report were found to interfere with nucleic acid production, a biological process essential for the rapid and uncontrolled cell growth that characterizes cancer.
Experiments conducted on mice also showed that tumor tissue sometimes reacted differently to certain chemicals than normal tissue, further reinforcing the idea that tumors and parasites might share biochemical traits.
Although the CIA document does not claim that cancer is caused by parasites, it does describe research suggesting that compounds designed to target parasites might also influence tumor growth.
The report remained largely unnoticed for years after its declassification, but it has recently resurfaced online, where it has fueled debate and speculation across social media platforms.
Some users have interpreted the document as evidence that potential cancer treatments may have been overlooked or ignored.
‘The Americans knew. They read it, classified it CONFIDENTIAL, and locked it in a vault for 60 years,’ one user wrote on X while sharing screenshots of the document.
Another post claimed: ‘The CIA knew from 1951 that cancer was parasites.’
However, the document itself does not support that conclusion. Instead, it describes a Soviet study that identified biochemical similarities between parasites and tumors and observed that certain compounds affected both.
Daily Mail has contacted the CIA for comment.
