PharmAust delivers COVID-19 antiviral breakthrough

ASX-listed pharmaceutical company, PharmAust continues to kick goals in its endeavours to develop antiviral treatment and prevention therapeutics for COVID-19. The company has once again demonstrated that its lead drug candidates monepantel and monepantel sulfone appear to show protection against cell death in non-human primate systems. Human clinical trials are now on the cards with production of the drug suitable for human consumption having already commenced.

Last year the company revealed monepantel’s antiviral activity for SARS-CoV-2, the virus causing COVID-19, for both primate and non-primate cells in two independent Australian laboratories. PharmAust has since upped the ante by appearing to demonstrate further antiviral activity in non-human primate systems.

The breakthrough comes on the back of a collaboration between PharmAust and the Leiden University Medical Centre in Holland which has been performing extensive testing to examine the effects of monepantel and monepantel sulfone.

Leiden University Medical Centre is a modern and internationally renowned biomedical research centre. Its Molecular Virology team has been working on coronaviruses for over 30 years, including the SARS and MERS viruses in 2003, 2012 and most recently SARS-CoV-2 since early last year. The current collaboration with PharmAust is being spearheaded by Dr Martijn J van Hemert at Leiden.

Results from the testing seem to show that monepantel sulfone shows signs of protection against cell death reaching levels greater than 95 per cent effectiveness at higher concentrations of the drug.

Monepantel on the other hand shows signs of antiviral activity at lower concentrations, however at higher concentrations loses effect. The company presumes the reason for the decline in effectiveness is due to monepantel’s low solubility in aqueous media.

PharmAust’s Chief Scientific Officer, Dr Richard Mollard stated: “Testing highly insoluble drugs such as MPL (monepantel) in established complex culture conditions is notoriously difficult. PharmAust is very grateful to Associate Professor van Hemert and his team for their extensive and exhaustive efforts with MPL. We look forward to updating the market as these programs continue.”

Associate Professor Martijn J van Hemert, principal investigator at Leiden added: “There are indications for an antiviral effect in these assays, but solubility issues under the conditions required for cell-based screening complicate analysis. Additional experiments will now be performed on SARS-CoV-2 infected human lung cell lines.”

Despite the challenges with solubility for monepantel, PharmAust’s clinical programs will remain unimpacted, according to management.

The company has developed a tablet form of monepantel which converts into monepantel sulfone in the body representing the dominant form in the plasma. PharmAust reports that the issues of solubility for administration to human patients is resolved through the tablet form of the drug.

PharmAust has wasted little time in turning its attention to developing an antiviral program to test the drugs in human cells. Good-Manufacturing-Practice-quality monepantel production that is suitable for clinical trials has already commenced at Syngene International, located in India.

As nations around the world struggle to manage their COVID-19 impacted economies, prevention and treatment solutions for the virus are becoming more important by the day. PharmAust is already looking the goods in such a quest and as testing of monepantel moves to human trials, all eyes will be firmly fixed on the Perth-based company.

Is your ASX-listed company doing something interesting? Contact: matt.birney@businessnews.com.au