A hydrogel capable of sequestering a range of cargos—from small molecules to large molecules such as monoclonal antibodies—shows promise as a drug delivery platform. Injected subcutaneously at tumor sites, this hydrogel, loaded with Herceptin, provided for the sustained release of the antibody, enhancing its retention within the tumors.
The hydrogel, consisting mostly of water, is based on a nontoxic, biodegradable polymer developed and tested by scientists from IBM and Singapore’s Institute of Bioengineering and Nanotechnology (IBN). These investigators report that their hydrogel, when used as a drug delivery platform for Herceptin, led to superior antitumor efficacy in an animal model, outperforming intravenous and subcutaneous delivery of Herceptin in solution.
The scientists published their results November 1 in Advanced Functional Materials, in an article entitled “Injectable Hydrogels from Triblock Copolymers of Vitamin E-Functionalized Polycarbonate and Poly(ethylene glycol) for Subcutaneous Delivery of Antibodies for Cancer Therapy.”
One of the study’s authors, James L. Hedrick, Ph.D., an advanced materials scientist at IBM’s Almaden Research Center, may seem an unlikely medical researcher, since his work usually focuses on microelectronics fabrication. Yet he adopted a matter-of-fact tone about IBM’s foray into the life sciences: “Drawing from our experience in materials innovation for electronics technology, we are now applying these techniques to the quest for improved health.”
IBM’s turn to life sciences isn’t exactly news. IBM started a nanomedicine polymer program four years ago with the mission to improve human health. It stems from decades of materials development traditionally used for semiconductor technologies.
IBM’s partner, IBN, conducted the animal studies. According to the paper describing these studies, “over the course of 28 days, the tumor shrank 77% when paired with the hydrogel via subcutaneous injection at the tumor site as opposed to 0% without it by intravenous injection.”
IBN group leader Yi Yan Yang, Ph.D., a co-author of the paper, said, “We have developed new, effective materials for nanomedicine, which has been one of IBN's key research focus areas since 2003. The sustained delivery of Herceptin from our hydrogel provides greater antitumor efficacy and reduces injection frequency. Thus, our approach may help to improve patient compliance, offering a better alternative to existing breast cancer treatments.”
The hydrogel, say the researchers, also exhibits many of the biocompatible characteristics of water-soluble polymers, which hold form in the body without completely dissolving. This allows the hydrogel to function as a depot for the drug to slow-release its contents in a targeted location directly at the tumor site over weeks instead of days. Once the drug has been delivered, the hydrogel biodegrades naturally and passes through the body.
Commenting on the hydrogel’s performance, Dr. Hedrick said, “It can help deliver drugs over an extended period of time without causing a significant immune response, effectively sending its contents directly to the tumor without harming healthy surrounding cells.”
“This technology can also be used to deliver other types of antibodies or proteins to treat different diseases,” added Dr. Yang.