MIT Researchers Create Drug-Eluting Implantable To Shrink Tumors

By Jof Enriquez,
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Researchers from Massachusetts Institute of Technology (MIT) and Massachusetts General Hospital have developed a new drug-eluting implant that can shrink pancreatic tumors.

Pancreatic ductal adenocarcinoma (PDAC) tumors, the most common type of pancreatic cancer, is known to be inherently resistant to chemotherapy intervention. This difficulty is compounded by the deep anatomical location of the pancreas within the abdomen, a lack of vasculature in pancreatic tumors that limits the penetration of chemotherapy drugs, and the pathologic development of fibrous tissue that block drugs from reaching the tumor. These factors contribute to rapid metastasis and poor prognoses among pancreatic cancer patients.

In order to overcome these barriers, MIT researchers designed a thin, flexible, biodegradable polymer film that can be directly implanted onto a pancreatic tumor. The implant is made of poly(lactic-co-glycolic acid), a polymer used in various drug delivery systems, including one to fight brain tumors, and other medical applications. The film can be rolled up inside a catheter, and, once implanted, it unfolds and wraps around the tumor, where it releases preprogrammed doses of a chemotherapeutic drug (paclitaxel) for up to 60 days.

In mice, the researchers compared how effective the implanted device was in shrinking pancreatic tumors, compared to traditional systemic chemotherapy wherein the drugs were injected.

"We compared the efficacy of systemic and local paclitaxel therapy on the patient-derived cell lines in an orthotopic xenograft model in mice (PDX). In this model, we found up to a 12-fold increase in suppression of tumor growth by local therapy in comparison to systemic administration and reduce retention into off-target organs," explained the researchers in their study abstract published in the journal Biomaterials.

“Our results underscore the urgent need for an implantable drug-eluting platform to deliver cytotoxic agents directly within the tumor mass as a novel therapeutic strategy for patients with pancreatic cancer,” the researchers wrote.

The film also acted as a physical barrier to prevent metastasis to nearby tissues. Moreover, only the side of the film that comes into direct contact with the tumor is coated with the chemotherapy drug. This, along with the limited number of blood vessels in the tumor, reduced the unwanted toxic effects of chemotherapy to nearby organs.

The implant offers a viable localized drug delivery system for existing and experimental anti-cancer agents.

“It’s clear there is huge potential for a device that can localize treatment at the disease site,” Laura Indolfi, a postdoctoral researcher in MIT’s Institute for Medical Engineering and Science (IMES) and the MGH Cancer Center, and one of the study’s lead authors, said in an MIT News story. “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.”

In addition to shrinking tumors, the film also can serve as coating for stents that reopen blocked bile ducts, which cause tremendous pain. Existing stent technologies also get blocked eventually and need to be replaced. With the new coating added, these stents should need to be replaced less often.

“We can extend the lifespan of these devices,” Indolfi said in the release. “Rather than being replaced every month they could be replaced every six months, or once a year.”

The researchers have launched a company, PanTher Therapeutics, to prepare for human clinical trials and continue device development.

Image credit: Bryce Vickmark