Singapore scientists develop hydrogel that improves delivery of anti-cancer drug

SINGAPORE - Singapore scientists have developed a new non-toxic hydrogel that is capable of shrinking breast cancer tumours more rapidly than existing therapies.

Developed by The Institute of Bioengineering and Nanotechnology (IBN) and IBM Research (IBM), the Vitamin E-incorporated hydrogel can be easily injected under the skin without causing any inflammatory response.

It then releases anti-cancer drugs in a sustained manner over several weeks. This reduces the need for frequent drug administration, paving the way for the tumours to be eradicated in fewer treatments.

IBN Group Leader, Dr Yi Yan Yang, said: "The sustained delivery of Herceptin from our hydrogel provides greater anti-tumour efficacy and reduces injection frequency. Thus, our approach may help to improve patient compliance, offering a better alternative to existing breast cancer treatments. This technology can also be used to deliver other types of antibodies or proteins to treat different diseases."

Breast cancer is the most common invasive cancer affecting women worldwide, including in Singapore. One in four breast cancer patients will have a significantly lower survival rate as they possess a particularly vicious type of cancer gene known as the human epidermal growth factor receptor 2 (HER2+), the team said.

This growth factor receptor causes rapid, unrestrained growth and division of cells in their breasts.

A therapeutic drug called Herceptin helps to combat this type of cancer by regulating the cancer growth. However, current methods of administering this drug requires intravenous infusion on a weekly basis, with each treatment session lasting 30 to 90 minutes.

The need for frequent administration and the accompanying discomfort may affect patient compliance adversely, the team said. Hence, the IBN and IBM researchers aimed to reduce the number of injections and injection time required by creating a biocompatible, biodegradable and injectable hydrogel that can be conveniently injected into the body and would release Herceptin in a sustained manner.

Through this, they were able to reduce the frequency of drug administration from weekly to only once in four weeks.

Recent clinical trials using subcutaneous injection of Herceptin shortened the injection time to around five minutes and were reported to have comparable therapeutic efficacy as traditional methods at the same dosing schedule.

The team said that the new drug administration method via IBN's and IBM's hydrogel offers a further improvement on these studies as it supplies Herceptin continuously over a prolonged period of time.

It also helped to shrink the tumours over fewer administrations. In animal studies with tumour-bearing mice, the tumours shrank in size by 77 per cent 28 days after the Herceptin-loaded hydrogel was injected subcutaneously.

The hydrogel did not evoke any chronic inflammatory response and degraded within six weeks post-administration.

The scientists have filed a patent on their hydrogel technology and said that they would like to engage pharmaceutical companies to further develop the hydrogel for future clinical applications.