The successful conclusion of its Phase II clinical trials has now opened the door to the Phase III stage, with commercialisation also in discussions.

Clinical stage oncology company, PharmAust (ASX:PAA), has made major progress in its quest to commercialise the monepantel (MPL) drug for pet dogs with B-cell lymphoma.

Following the treatment of 15 pet dogs during its Phase IIa and Phase IIb studies, the company has successfully achieved the two interim trial primary endpoints: objective tumour regression and increased progression-free survival.

This was achieved by demonstrating sufficient and statistically significant anti-cancer activity in the animals.

Shares in PharmAust rose by almost 5% in morning trade to 9.3c following the announcement.

The successful outcome will pave the way for the development of Phase III trials, and opens the door to explore the value of MPL in other canine cancers.

PharmAust will also seek out leading global pharmaceutical companies as partners to co-develop and commercialise the MPL in a range of veterinary cancers.

“We set the bar very high in our studies of MPL in canine B-Cell lymphoma,” said PharmAust’s Chief Scientific Officer, Dr Richard Mollard.

He added that the company’s investment in defining a dosing regimen “will now pay dividends in the Phase III and commercialisation programs”.

Results from the Phase IIa and Phase IIb studies

Multi-centric high grade B-cell lymphoma is one of the more aggressive cancers to study in canine oncology.

Over the 28-day study period, PharmAust produced a compelling outcome which included an objective regression in one of the first eight dogs, with some tumours resolving completely.

It also observed objective disease-stabilisation or better in six of the first 15 pet dogs treated.

Two pet dogs with advanced and extensively disseminated disease, and one other dog with less extensively disseminated disease, were treated with lower dose MPL. However, these were withdrawn due to disease progression during the trial.

The remaining 12 treated pet dogs completed the full 28 day trial period.

According to Dr. Mollard, in addition to the standard measurements of target superficial lymph nodes that are characteristic of many such trials, PharmAust also incorporated comprehensive thoracic X-ray and abdominal ultrasound analyses into the trial design.

“This means that designation of stable disease in this trial really means comprehensive stable disease, not superficially stable disease as per many other trials where progression might be hidden somewhere else in the body,” he said.

Published mean and median times for untreated dogs show that normally, eight of these 15 pet dogs would have been euthanised by day 29/30 with aggressively progressive disease and poor quality of life.

Comprehensive data are not yet available ex-trial, but available reports are that at least six pet dogs continued with either MPL alone, or in combination with prednisolone.

Dr Mollard explained that normally at this stage, PharmAust would continue with an extension of the Phase II Bayesian approach, continuing to treat up to 46 dogs according to the prospectively defined full Phase II design.

“But advice from the administering veterinarians is to instead immediately commence preparations for Phase III. In these preparations PharmAust will fine tune the optimal dose for the Phase III trial,” he said.

Other cancer applications

PharmAust and its team of vets are confident that MPL’s ability to target a central metabolic pathway associated with tumour growth means that it will have application in other canine cancers.

As it seeks out global partners, the company said it has been approached by animal healthcare companies in the US and Germany for discussions.

To help with the discussions, PharmAust last month engaged the services of Dr. Kim Agnew, a highly experienced executive who worked for 20 years at Elanco Animal Health and for five years at Merial, now Boehringer Ingelheim.

“Phase III studies enable a deeper investigation of how Monepantel can best become part of a canine oncologist’s therapeutic portfolio. This will be a very exciting part of the development”, Dr Agnew commented.

Following the trials, the company has also established a therapeutic window for clinical trials in human cancers.

According to PharmAust, achieving stable disease in primary cancerous lesions as well as in metastatic disease could have substantial value in human cancer therapy, particularly if progression-free survival correlates with overall survival.

In its previous small Phase I trial in humans, a stable disease was observed where the participants had been admitted with progressive disease following the failure of other treatments.

This article was developed in collaboration with PharmAust , a Stockhead advertiser at the time of publishing.

This article does not constitute financial product advice. You should consider obtaining independent advice before making any financial decisions.