Clinical-stage biotechnology company PharmAust (ASX: PAA) has lodged a patent application for the use of its lead drug monepantel in a range of viral diseases.
The PCT (Patent Co-operative Treaty) patent is directed towards the use of monepantel and other aminoacetonitrile derivatives as antiviral agents.
It claims an earliest priority date of 11 May 2020.
PharmAust expects the application will be open for public inspection in November.
Intensively studied drug
Monepantel has been intensively studied by the industry from different perspectives relating to its efficacy against different species and stages of parasites, mode of action, metabolism, pharmacokinetics, toxicity, resistance and ecotoxicity.
It is currently employed mainly as an anthelmintic (antiparasitic) drug for livestock and has a broad-spectrum of activity against gastrointestinal nematodes of sheep.
PharmAust’s use of monepantel is primarily focused on developing cancer therapeutics for humans and canines.
The drug has been found to act in a previously unrecognised ”off-target” fashion with the mTOR (mechanistic Target Of Rapamycin) pathway which is an important regulatory pathway in mammalian cells.
PharmAust has previously stated that molecules such as monepantel which target the mTOR pathway have relevant therapeutic value across a wide range of diseases.
In April, PharmAust announced monepantel and its metabolite monepantel sulfone could potentially be used as antiviral therapeutics in the prevention and treatment of coronavirus.
The finding has been backed by results from extensive testing of cultured cell infection models of SARS- CoV-2 (the virus which causes COVID-19) at Leiden University Medical Centre in the Netherlands.
Testing examined the effects of both drugs in specialised COVID-19 non-human primate systems and generated indicative data to demonstrate their antiviral (protection against cell death) activity.
Earlier this month, PharmAust reported that monepantel tablets could maintain a shelf-life well within limitations for veterinary and human use.
Independent stability tests over a 24-month period in a controlled temperature of 25°C with 60% humidity showed the tablets could be safely stored and remain within specifications relevant to veterinary and human clinical trials.
The company said product stability and shelf-life are important criteria as it moves toward a phase III trial of monepantel and identifies potential commercial partners.