• Animal research shows mTOR inhibitor drugs could reverse the ageing process
  • Studies also show that they make excellent potential anticancer agents  
  • We profile ASX-listed PharmAust, which has program developing an mTOR inhibitor drug


Ageing is a complex biological process that involves a combination of genetic, environmental, and lifestyle factors.

The consensus within the medical world is that while some interventions could slow down or delay the ageing process, they cannot entirely reverse the fundamental changes that occur in the body over time.

But that could soon change, with a kidney transplant drug called rapamycin now becoming the latest fixation of people trying to fight ageing.

Rapamycin is a medication that belongs to a class of drugs called mTOR inhibitors, and was initially developed by scientists at the pharma company Wyeth (now part of Pfizer) as an immunosuppressive drug to prevent rejection of transplanted organs.

The drug works by inhibiting the activity of a protein called mTOR (mechanistic target of rapamycin), which is involved in cellular growth, metabolism, and immune response in mammals including humans.

Recent studies have shown that rapamycin could in fact fight ageing too, with research in animal yielding encouraging results.

The results demonstrated that rapamycin can extend the lifespan of yeast, worms and flies. Studies in mice have also shown an increase in lifespan.

Since then, numerous other studies have explored rapamycin’s potential anti-aging properties, as well as its impact on age-related diseases – although there is still little evidence of its longevity benefits in humans.


What is the mTOR pathway?

This development has piqued the interest of investors and put the spotlight on studies being conducted on mTOR inhibitor drugs.

US-based longevity focused biotech, Cambrian Biopharma, recently signed a licensing agreement with Novartis to advance its novel drug targeting the the mTOR pathway.

In a nutshell, mTOR is a protein kinase that plays a central role in regulating our cellular processes – including cell growth, metabolism, protein synthesis, and autophagy.

Autophagy, a mechanism by which our cells remove and recycle themselves, naturally decreases with age and can lead to a buildup of what’s called cellular “junk”.

When this happens, it’s harder for cells to repair themselves and work efficiently, accelerating the ageing process and increasing the chances of getting age-related diseases like cancer.

mTOR inhibitor drugs work by regulating and suppressing this mTOR pathway, making them excellent potential anticancer agents that could inhibit the uncontrolled growth and survival of cancer cells.


PharmAust’s mTOR inhibitor drug

On the ASX, a company which has a development program on an mTOR drug is PharmAust (ASX:PAA).

The company’s lead drug, monepantel (MPL), targets the mTOR pathway to treat cancer growth and neurodegenerative diseases.

Recent research has shown that MPL has broad anti-cancer effects across multiple cancer types including melanoma, lung, breast, brain, colorectal, prostate, and ovarian.

Independent tests also showed that MPL can retain long-term shelf-life and product stability, with at least 12 months of tablet shelf-life.

The drug has been evaluated in Phase 1 clinical trials in humans, and Phase 2 clinical trials in dogs.


Phase 1/2 clinical trial on motor neurone disease (MND)

For this trial, PharmAust has confirmed that all blood samples from the interim analysis have been collected and submitted for analysis.

PharmAust will continue with MPL dose escalation for Cohorts 3 and 4, to determine the optimum dose for a Phase 2 trial.

A favourable interim analysis will allow the company to prepare for a Phase 2 MND clinical trial, and a Human Cancer Phase 2 clinical trial on this disease.


Phase 2 trial on canines with B-cell lymphoma

The latest results showed that two dogs had a partial response (>30% decrease in cancer tumour), and eight others have enjoyed a stable disease response.

Meanwhile one dog patient has surpassed 300 days with stable disease and continued excellent Quality of Life (QoL), as attested by dog owner testimonials.

PharmAust says assay results from 10 x plasma samples are expected by late May, while the MPL Phase 2 trial itself is expected to be completed by mid-2023.


Phase 2 human cancer trial

Not only does PharmAust have clinical trials underway in MND in humans and cancer in canines, the company is set for further trials in human cancer.

This could provide PharmAust with multiple ‘shots on goal’ at a +$1Bn drug success.

Recent data from PharmAust’s B-Cell Lymphoma cancer trial in canines suggests positive correlation, and possible translation, for targeting multiple different cancers in humans.

If MPL human trials return similar efficacy as in canines, this would be an absolute game changer and major entry into the billion dollar human cancer industry.


PharmAust share price today:




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