Singapore team develops slow-release hydrogel with hep C potential

A*STAR researchers including Mutoichi Kurisawa (right)

Hydrogels are known to give drugs an edge when it comes to quick deliverability and simple application, but their long-term efficacy has come into question as their release rates are difficult to control. Researchers in Singapore have developed a new kind of hydrogel that prevents this premature release and allows for fewer doses in patients with chronic diseases like hepatitis C.

The researchers at Singapore's A*STAR academy created a gel using polyethylene glycol (PEG) that features 3-D microscopic structures acting as reservoirs for drugs. The interferon drugs that fit into these reservoirs won't leak prematurely, the scientists claim, because of the presence of PEG on the drugs themselves. They flow freely in and out of the reservoirs, but remain within the gel until they are finally released into the body.

A hydrogel is a material that has the properties of both a solid and a liquid due to its polymer chains. This interchanging nature gives the gel the ability to function as a drug delivery tool with unique attributes.

"Our hydrogels can significantly extend the half-life of hepatitis C drugs by up to 10 times longer than current treatment," lead researcher Mutoichi Kurisawa said in a statement. "Half-life is the time taken for the amount of drugs in the body to be reduced by half, and is a standard indicator of the duration of drug action. This work improves the therapeutic efficiency of the drugs, while reducing the need for frequent injections."

In cases of hepatitis C, the long-term delivery available with this hydrogel could improve the treatment by making it more consistent over time. It would also reduce the frequency of uncomfortable injections that can cause a patient to grow tired or depressed, according to a release.

The scientists showed that the hydrogel containing PEGylated interferon had the same effectiveness as 8 injections of the medication alone and that the hydrogel degraded naturally in the body.

The scientists published their study in the journal Biomaterials.

- here's the A*STAR release
- and here's the abstract