Patrys Ltd (ASX:PAB) has completed its first engineering run of lead asset PAT-DX1, an antibody fragment derived from the original mouse-model deoxymab antibody 3E10.
The company is scaling up the production of clinical grade PAT-DX1 with a view to initiating first-in-human studies in the first half of this year.
Production yield from the fermentation process was consistent with small-scale pilot runs, however, purification resulted in lower drug product recoveries than expected.
Patrys is working with its contract development manufacturing organisation (CDMO) to implement improvements for the large-scale purification process.
The company anticipates that another engineering run for PAT-DX1 using an improved purification process will begin in the second quarter of this year.
Confident improvements will yield returns
Patrys CEO and managing director Dr James Campbell said: “While we were very happy with the yield from the fermentation process in our first engineering run, we are clearly frustrated that the purification process did not perform as well as expected.
“We have worked closely with our CDMO to identify and resolve the purification issues and are confident that the changes being implemented will improve the yield from this step.
“This set-back to the timing of our PAT-DX1 program is material but is offset by the significant advances being made with the PATDX3 manufacturing program and a range of business development activities.”
Toxicology studies
Non-Good Laboratory Practice (GLP) toxicology studies will take place as planned with available drug product, although the lower yield from this first engineering run will impact subsequent GLP toxicology studies, which will in turn delay the initiation of the first planned human study of PAT-DX1.
The GLP toxicology studies are required to be conducted using drug product generated from the same manufacturing process that will be used for the Phase 1 clinical trial.
Accordingly, Patrys is working with its toxicology service provider to reschedule the GLP rodent and non-human primate toxicology studies to begin in third quarter, 2022.
This six-month delay will impact the timing of the first in human study of PAT-DX1, which is now planned for mid-2023.
R&D tax refund
Patrys' wholly-owned subsidiary Nucleus Therapeutics Pty Ltd has received a $1,188,581 R&D Tax Incentive Refund for the 2020/2021 financial year.
The Research and Development Tax Incentive is the government’s key mechanism to stimulate Australian industry’s investment in R&D, encouraging companies to engage in R&D benefiting Australia, by providing a tax offset of up to 43.5% for eligible R&D activities.
Dr Campbell said: “This rebate, combined with Patrys’ strong financial position will be applied to further developing the company’s deoxymab technologies.
"We greatly appreciate the support of the Australian Government with this incentive, as Patrys advances both PAT-DX1 and PAT-DX3 towards the clinic.”
About Patrys
Patrys is using antibodies to develop revolutionary therapies for the treatment of cancer. Its deoxymab platform was originally isolated from a mouse model of the human autoimmune disease systemic lupus erythematosus (SLE), producing the antibody called 3E10.
This has biological properties not normally found in human antibodies, including cancer targeting, blood brain barrier penetration, cell penetration and an inhibitive effect on DNA damage repair.
These unusual properties have made a range of therapeutic approaches to the treatment of cancer possible through existing, small molecule or full antibody therapies.