|The paclitaxel-delivering polymer film--Courtesy of Bryce Vickmark, MIT|
Pancreatic cancer is usually treated with intravenous chemotherapy, but these injections often fail because the pancreas lies so deep within the abdomen. Now researchers from MIT and Massachusetts General Hospital have developed a minimally invasive implantable device that delivers chemo drugs directly to pancreatic tumors.
The implant is a thin, flexible film made from the polymer PLGA, which is already used in drug delivery and medical applications. The film can be rolled up and inserted via catheter, so implanting it surgically is relatively simple, MIT said in a statement. Once the film reaches the pancreatic tumor, it unfolds and wraps the tumor. The drugs embedded in the film are then released from its tumor-facing side, which reduces side effects on other tissues.
"Because it's very flexible it can adapt to whatever size and shape the tumor will have," said Laura Indolfi, a lead author of the study, in the statement. The study compared the device's efficacy to that of traditional chemotherapy in mice carrying human pancreatic tumors.
One group of mice was treated with the implant carrying the chemo drug paclitaxel, while the other group received injections of the drug for four weeks, simulating the treatment for human patients. The researchers found that tumor growth slowed in mice with the implant. In some cases, the tumors even shrank. After four weeks, the implant group showed 5 times the paclitaxel concentration in their tumors that the intravenous group did.
In addition to successfully delivering the drug to the pancreas, the team observed other positive effects. Pancreatic tumors have few blood vessels, which makes it harder for drugs to enter them. On the flip side, this made it more likely for implant-delivered paclitaxel to remain in the tumor without spreading to nearby organs.
|Left to right: Matteo Ligorio, MGH researcher; Laura Indolfi, a postdoc in MIT's Institute for Medical Engineering and Science (IMES) and the MGH Cancer Center; and Elazer Edelman, a professor of health sciences and technology at MIT--Courtesy of Bryce Vickmark, MIT|
"This combination of local, timed, and controlled release, coupled with the judicious use of critical compounds, could address the vital problems that pancreatic cancer has provided as obstacles to pharmacological therapy," said Elazer Edelman, a senior author of the paper.
The device's applications don't stop at pancreatic cancer. It could be useful in treating other hard-to-reach tumors, such as those in the gastrointestinal tract. And because the device only secretes the drug from its tumor-facing side, it could be used to treat patients who experience such toxic side effects from chemo that their dose cannot be increased.
The team is preparing for clinical trials and has started a company, PanTher Therapeutics, to develop the implant for patient use. Meanwhile, University of North Carolina researchers are working on an implantable device for pancreatic cancer that delivers a four-drug cocktail using a local electrical current.