Hopes for new painkiller

Groundbreaking discovery in Tassie mud sample

MOLECULES in a mud sample from Tasmania show promise as the basis for a potential new class of painkiller as potent as opioids but without the propensity for addiction.

University of Queensland chemist Rob Capon first suspected the molecules may have analgesic properties 16 years ago when he analysed a marine fungus found in a mud sample collected near a boat ramp in the Huon Valley.

Professor Capon, of UQ’s Institute for Molecular Bioscience (IMB), observed that peptides in the fungus looked similar to human endomorphins, the body’s natural painkillers.

It was a chance finding, given his lab was not looking for a molecule to turn into an analgesic.

“Some people will go out and do a screening campaign looking for a particular type of drug,” Prof Capon said.

“We weren’t doing that. We were just looking for interesting chemistry.

“Once you find the interesting molecules, at that point you have to apply some broader knowledge and say: ‘I wonder what we could use them for, and that was the serendipitous aspect of this. I noticed they were similar to endomorphins.”

At the time, Prof Capon did not have enough research funding to rigorously pursue his finding.

But after joining forces with IMB colleague Professor Paul Alewood and University of Sydney pharmacologist Macdonald Christie, they have modified the molecules to create a new type of analgesic, dubbed bilactorphins.

They have a patent on their discovery and are hoping to collaborate with a pharmaceutical company.

Prof Capon said early animal testing had shown bilactorphins were as potent as other opioids, such as morphine, but potentially without the adverse side-effects, such as suppression of breathing and possibility for addiction.

With the backing of a drug company, if bilactorphins live up to their promise, the scientists say they could be available as a safer, new class of painkiller in a decade. Prof Capon plans to develop a “Soils for Science” program aimed at building a library of microbes by asking citizens to send in dirt from their backyards.