Proprietary TPE could allow drug-eluting breast implants for cancer patients

This so-called "Biorubber" belongs to a family of polyisobutylene-based thermoplastic elastomers whose biocompatibility has been demonstrated in vitro and in vivo, according to the university. In fact, one version of the material is currently FDA approved and seeing use in a drug-eluting stent.

For women seeking reconstructive surgery after a mastectomy, Puskas sees Biorubber as a novel, soft gel-filled breast implant that would significantly reduce or eliminate the risk of leakage and ruptures in implants, and may reduce the incidence of capsular contracture, ultimately promising a safer alternative for women choosing breast implants.

The University of Akron noted that today's implants are solely based on silicone, due to the implant scare of the 1990's where there was a wholesale switch to saline-filled implants, but the shell material remained essentially the same. According to Akron, today's implants still have around a 30% documented failure rate.

Puskas notes that the permeability of the new Biorubber is at least two orders of magnitude lower than that of silicone rubber. It also boasts superior fatigue properties, and is lighter than silicone, in addition to providing rubber-like properties without additional chemical crosslinking.

A worthy goal
Puskas and her team have a stated research goal to develop and create prototype breast implants and prostheses for FDA approval. In year one, the plan calls for prototype production, and mechanical and chemical testing. In year two, the researchers are aiming for in vitro testing and in vivo animal testing. At the end of the second year, the hope is a device would be ready to present to FDA as a class 3 medical device for the beginning of Phase I clinical trials.

To meet these goals, the University of Akron is seeking donations for producing the new Biorubber in an FDA-approved GMP facility and prototype building and conducting the initial testing protocols required by the FDA.

Drug-eluting implant
In terms of a implants that could serve double or triple duty as diagnostic devices and drug delivery systems, the researchers note that the material can be spun into a fiber mat, and those fibers, which can be attached to the implant, could encapsulate various cancer-fighting drugs. By delivering drugs directly to the cancer cells, the amount of drugs needed for treatment could be reduced, lessening their side effects.

Researchers can also encapsulate a diagnostic agent to reveal the presence of cancer cells and their location as well as help determine the drug's efficiency. Finally, the implant could be coated with drugs to help reduce the risk of inflammation in the tissue surrounding the implant.

In March, Puskas and her team were five winners of the General Electric healthymagination Breast Cancer Challenge. Their research was selected among 500 entries from 40 countries. As a winner, they received a $100,000 seed award and will be given access to additional funding for further research and development.