Biodegradable Implant Holds Promise As Ovarian Cancer Treatment

Ovarian cancer patients normally undergo two procedures: surgery to remove the tumour and chemotherapy to destroy any remaining cancer cells. The chemical vehicle used to intravenously transport anti-cancer drugs such as paclitaxel during chemotherapy can often cause serious side effects, including hypersensitivity and nervous system disorders.

The PoLi implant is a small hydrogel infused with cancer-killing drugs. It is applied directly to the ovary after the removal of the tumour and steadily releases the drug over a two-month period. The implant is biodegradable and dissolves naturally — it does not have to be surgically removed.

“The PoLi implant is showing promise in the treatment of other cancers, including head and neck,” Piquette-Miller said. “We are also developing an injectable gel-based formulation that could be administered directly to the tumour site without surgery. We would consider it for breast and prostate cancers.”

PoLi is the result of four years of collaboration between researchers who come from different scientific backgrounds. Allen, a materials science chemist, designed the implant, while Piquette-Miller, a molecular pharmacologist, determined the drug concentrations and PoLi’s potential applications. “Our team works well because there’s a real complement of expertise,” Allen said. “We also have a large number of students who are getting incredible interdisciplinary exposure.”

Justin Grant, a PhD candidate in Allen’s lab, has been with the project since Day 1. “Under Dr. Allen’s guidance I was able to design the PoLi drug delivery system, which became the focus of my PhD project,” Grant said. “As this system developed, we sought collaboration with Dr. Piquette-Miller’s lab for their expertise in pharmacokinetics and drug transporters. This implant system that started at a lab bench now has the potential to improve the quality of life for thousands of people.”

To move PoLi one step closer to treating humans requires clinical trials. A possible partnership with industry is being explored through Innovations at U of T. “The data showing the drug release profile, the lack of toxicity and the biocompatibility of the PoLi technology tell us that this technology has limitless potential,” said Jennifer Fraser, director of commercialization-life sciences at Innovations at U of T. “It would be a valuable asset to any company working in the drug delivery or cancer treatment space.”

Companies looking to develop PoLi for healthcare uses unrelated to cancer have also shown interest in the patented technology. “We’ve been approached by companies looking to develop it for wound healing and ocular diseases,” said Allen.

On advancing PoLi as a cancer treatment, the duo say they are keeping their options open. “Either we get the funding to advance the studies on our own or we work with industry,” Piquette-Miller said. “But our goal is to have both the implant and injectable formulations developed and see them go forward in the treatment of cancers.”