Researchers have developed a small, implantable device for delivering chemotherapy drugs directly to pancreatic tumors. Tests in mice showed it was up to 12 times more effective than giving the drugs intravenously, which is how most patients receive them.
The researchers describe how they developed and tested their innovation in a paper published in the journal Biomaterials.
The device is a thin, flexible film that can be loaded with drugs, rolled into a narrow tube and inserted into a catheter. Once it is implanted in the pancreas, the film unfolds and conforms to the shape of the tumor.
The drugs embedded in the film are released over a predetermined period of time. The film is designed so the drugs only release from the side that is in contact with the tumor, minimizing side effects on nearby organs.
One of the lead authors of the paper, Dr. Laura Indolfi, of the Massachusetts Institute of Technology (MIT) in Cambridge, says there is huge potential for a device that can localize treatment for pancreatic cancer at the tumor site. She notes:
“You can implant our device to achieve a localized drug release to control tumor progression and potentially shrink [the tumor] to a size where a surgeon can remove it.”
One of the reasons that pancreatic cancer is the third leading cause of cancer deaths in the US and has a very low survival rate is because it is very difficult to get chemotherapy drugs into the pancreas, which is located deep inside the abdomen.
Injections of chemotherapy can also fail because pancreatic tumors have few blood vessels through which the drugs can enter, and they often surround themselves with a thick, fibrous coating that keeps drugs out.
It is very difficult to get chemotherapy drugs into the pancreas, which is located deep inside the abdomen.
More effective than injected chemotherapy
In a bid to cut down the lab-to-clinic translation time, the researchers made the drug-eluting film out of currently approved materials and drugs.
The film is made from a polymer called PLGA, which is widely used in drug delivery and other medical applications. “Because it’s very flexible,” says Dr. Indolfi, “it can adapt to whatever size and shape the tumor will have.”
The team tested the device in two groups of mice implanted with human pancreatic tumors. One group received the implant loaded with the chemotherapy drug paclitaxel, and the other received the drug via injections for 4 weeks, mimicking the treatment in patients.
In the mice with the implanted device, tumor growth slowed down, and in some cases shrank. The researchers also found an increase in dead cancer cells surrounding the targeted site. These are easier to remove during surgery than live cancer tissue.
After 4 weeks, the concentration of paclitaxel inside the tumor in the implanted mice was five times greater than in the tumors of the mice treated by injection. Plus, because there are few blood vessels in pancreatic tumors, the drug tended not to spread to nearby organs, thus preventing toxic side effects in healthy tissue.
The team also noted that the film acted as a physical barrier that reduced metastasis – the migration of cancer cells – to nearby organs.
The researchers are now planning to test the device in a clinical trial for human patients. They also see potential for the film to be used to treat other cancers with hard-to-reach tumors and as a coating for stents in pancreatic cancer patients who often suffer from bile duct blockage, which interferes with digestion and is very painful.
Together with her colleagues, Dr. Indolfi has started a company called PanTher Therapeutics, to further develop the device for patient use. She concludes:
“The greatest benefit of this device is the ability to implant it with minimally invasive procedures so we can give a tool to oncologists and surgeons to reach tumors that otherwise would be difficult to reach.”
Credit: Catherine Paddock, http://www.medicalnewstoday.com
Picture Credit: http://www.medicalnewstoday.com/info/pancreatic-cancer