Starving superbugs

In recent years the world has become increasingly aware of a rising threat. Antibiotic-resistant bacteria, or “superbugs”, are drastically reducing clinicians’ ability to treat common infectious disease.

If left unchecked, it’s estimated they could claim up to 10 million lives annually by 2050. But progress is being made. Multiple alternative treatments are being explored—and a novel University of Adelaide-developed therapy is producing exciting results.

"They can’t resist eating the other key compound, gallium-protoporphyrin, which mimics the bacteria’s favourite iron source, and poisons them. I call it toxic chocolate!"Dr Richter

A research team in the University’s Otolaryngology, Head and Neck Surgery Group has created a topical gel treatment for chronic sinus infections that significantly outperforms traditional antibiotics. According to the group’s leader, Professor Peter-John Wormald, in double-blind randomised studies, the treatment, called Def-GaPP, removed an incredible 80 to 90 per cent of recalcitrant infections. In the same tests, standard antibiotics removed just 10 per cent.

Significantly, it’s also unlikely bacteria will become resistant to the therapy. Dr Katharina Richter, a key researcher in Def-GaPP’s development, says this is the result of disrupting the bacteria’s food pathways, rather than targeting specific bacterial mechanisms like antibiotics do.

“Def-GaPP is a combination therapy with a dual action,” Dr Richter explains. “It works by first starving bacteria of iron—their preferred food source—using a compound called deferiprone. This makes the superbugs super hungry.

“Then they can’t resist eating the other key compound, gallium-protoporphyrin, which mimics the bacteria’s favourite iron source, and poisons them. I call it toxic chocolate!”

Currently in clinical trials, Def-GaPP is proving particularly effective against the common and sometimes deadly bacterium Golden Staph.This, together with a couple of other important characteristics, means its benefits could stretch well beyond sinus infections.

Katharina Richter

“Deferiprone has very strong anti-inflammatory and wound healing properties,” Dr Richter continues. “So Def-GaPP should also be particularly well suited to treating infected wounds.”

Dr Richter conducted much of the research underpinning Def-GaPP while studying her PhD at the University on a partial scholarship from the Florey Medical Research Foundation. She credits the scholarship for helping her acquire particular skills critical to the treatment’s development.

“The scholarship allowed me to attend a major overseas conference, where I met Professor Tom Coenye, an international expert in microbiology and novel antibacterial treatments. I subsequently visited his laboratory in Belgium, and learned essential research techniques that really accelerated my progress.

“Without the Florey scholarship, Def-GaPP may not be at the advanced stage it is today.”

Learn more about Dr Richter