Noxopharm Ltd (ASX:NOX) has passed a milestone in securing the future commercial value of Veyonda® with the US Patent Office allowing key abscopal response claims for the company’s DARRT immuno-oncology treatment.
The patent claims relate to the use of a combination of Veyonda and radiotherapy, including external beam radiotherapy (EBRT), with the purpose of generating abscopal responses in patients with metastatic prostate cancer.
These claims are fundamental to helping secure the commercial success of the DARRT (Direct and Abscopal Response to Radiotherapy) therapy involving a combination of Veyonda and low-dose EBRT.
Elusive form of immunological response
The abscopal response triggered by radiotherapy remains a highly sought but elusive form of immunological response considered potentially disruptive to most other forms of cancer therapy.
Noxopharm CEO and managing director Graham Kelly said: “We see the allowance of this patent application as a major win for the company in our goal of seeing DARRT therapy become a mainstream cancer treatment.
"Treating metastatic cancer through an abscopal response is arguably the best-tolerated and least destructive form of cancer therapy. Its ability to trigger long-term remission of some or all tumours in the body in a well-tolerated, non-toxic and low-demanding way for the patient clearly marks it as a potentially disruptive treatment.”
Investors have also responded positively with shares as much as 4.32% higher this morning to A$0.605.
“Remarkable 25% abscopal response rate”
“The challenge has been in moving the abscopal response rate from its current very low base.
"We believe we have met that challenge with a remarkable 25% abscopal response rate in our first clinical effort.
“While those responses were partial, our Phase 2 DARRT study is hoping to take these responses to another level by stepping up the intensity of Veyonda treatment.”
Immuno-oncology treatment
DARRT therapy is a form of immuno-oncology treatment. It involves the delivery of a short course of a low dose of radiotherapy to a single tumour in the body of a patient with metastatic disease.
The aim is to trigger a local immune response in the irradiated tumour that spills over into an all-of-body immune response resulting in the resolution of all (complete response) or some (partial response) of the other tumours in the body.
Most solid cancers, including the common prostate, breast and colorectal cancers, have proved to be overwhelmingly resistant to immuno-oncology (IO) treatments to date. This includes immune checkpoint inhibitors and CAR-T cell therapy.
Against that background, Noxopharm's DARRT-1 study already has delivered a 25% partial abscopal response rate in men with late-stage prostate cancer, something that the company is confident can be repeated in other forms of solid cancer.
Compared to current IO treatments, the abscopal response is substantially better tolerated, potentially effective across a broader spectrum of cancer types, considerably more affordable, and more accessible.
However, the challenge remains developing a method of lifting the abscopal response rate to a level where it will be accepted as a mainstream treatment.
Seeking expanded patent coverage
“We also are expanding into breast and lung cancer which provides us with the future opportunity to seek expanded patent coverage,” Kelly said.
"On what we have seen to date, we believe that DARRT therapy has the potential to go on to become a disruptive cancer treatment across most forms of cancer, starting with prostate cancer, which is why the patent news announced today is so important.”
The patent, which will be in force until at least April 6, 2037, covers Veyonda in combination with any form of radiotherapy designed to induce an abscopal response in prostate cancer patients.
Noxopharm believes that this patent action underpins a potentially medically significant and highly lucrative future for Veyonda.