Microbes cop a double whammy with new drug

Perth biotech Chemeq Ltd (ASX: CMQ) has developed a new kind of antimicrobial that may revolutionise agriculture and reduce the development of drug-resistant bacteria.

The company is making big claims that its unique polymeric antimicrobial drug, CHEMEQ, acts on all types of microorganisms including bacteria, viruses and fungal pathogens, does not cause side-effects, and does not enter the bloodstream or flesh of the animal and is not passed on to humans in food.

"For the first time we have a biologically active antimicrobial without side-effects," said Chemeq CEO and chairman Dr Graham Melrose.

"This product has the double whammy ? efficacy and safety. Most products have either one or the other, not both."

And the drug has friends in high places ? the US Food and Drug Administration (FDA) was so impressed with Chemeq's field trial data that it has proposed fast-track approval for the antimicrobial drug, describing it as a "therapeutic breakthrough".

The largest market for CHEMEQ is as a treatment for piglets to prevent post-weaning colibacillosis (PWC), a disease of the upper intestinal tract associated with E. coli infection. PWC causes death and failure to thrive in piglets and the market for the control of intestinal E. coli infections in piglets is estimated to be more than $1.2 billion in industrialised countries alone. The use of human antibiotics in piglets to control PWC has been linked to the development of antibiotic resistant strains of bacteria, which are then transmitted to humans via food. The presence of residual antibiotics in food is also a problem. These issues have led to regulatory agencies restricting the use of human antibiotics for animal purposes.

In field trials, Chemeq demonstrated significantly lower intensity of diarrhoea in piglets treated with CHEMEQ than in piglets treated with vaccines, antibiotics or untreated. The company also examined the safety of the product by testing the effects of high doses, and the effects of the drug in the bloodstream of the animal.

Chemeq has identified a second important market in the $6bn poultry industry. Initial studies have demonstrated that chickens given CHEMEQ gained up to 20 per cent more weight than untreated chickens.

Chemeq has a second product in the pipeline. CHEMYDE is a preservative for use in the cosmetics, toiletries and pharmaceutical industries, a $500m worldwide market. The company plans to build a commercial scale manufacturing plant near Perth, to be operational by January 2003.

How CHEMEQ works

CHEMEQ has a unique mode of action. It is a large polymeric molecule that interacts with surface proteins on the microbe via an aldehyde group, thus causing disruption of the cell membrane. As it does not recognise specific proteins or sugars as traditional antibiotics do, changes to the surface proteins expressed by the microbe do not prevent the action of CHEMEQ and thus resistance does not evolve.

CHEMEQ is larger than traditional antimicrobials. Because it is too big to cross biological membranes such as the skin or the lining of the gastro-intestinal tract, it can't enter the bloodstream, so that toxic, allergic and inflammatory reactions are non-existent. The drug is activated in the intestinal tract by changes in pH, and is naturally excreted via the faeces, so it doesn't cause contamination of the carcass.