A booster for immuno-oncology drugs
SYDNEY, Australia—Touting a new, more robust class of immune-oncology drugs to date, Noxopharm has released data from the first series of preclinical studies confirming that idronoxil (IDX), the active ingredient in the company’s anti-cancer drug candidate, Veyonda, not only activates, but potentially boosts the function of current immuno-oncology drugs.
The studies confirm that IDX activates cells associated with both arms (adaptive and innate) of the immune system and it increases functional natural killer (NK) cells and CD4+ (T-helper) cell numbers, thus positioning Veyonda (previously known as NOX66) on the vanguard of a global effort, Noxopharm announced April 16.
The studies involving human cell and animal experimental systems are part of a coordinated collaboration between the company and a number of prominent universities and research institutes in Sydney and Melbourne, Australia and Hong Kong.
Dr. Greg van Wyk, CEO of Noxopharm, says, “Veyonda appears to be a truly versatile drug candidate, with these immuno-oncology effects having the potential to complement its radio-enhancing and chemo-enhancing functions across a broad range of cancer types. We have chosen the word potential, here, since this represents a hypothesis and has not yet been demonstrated. But this is a sensible hypothesis because currently available immuno-oncology agents engage the adaptive immune system only, but not the innate immune system.”
“This exciting discovery supports our strategy of combining Veyonda with radiotherapy or chemotherapy, as engaging the immune system to enhance the effect of these treatments,” he adds. This kind of theory “has seen a revolution in cancer care in recent years.”
Furthermore, “our studies have not demonstrated increased toxicities to date,” van Wyk says. “We have also been able to use lower doses of chemotherapy and radiation and still achieve positive responses. Studies have shown that isoflavones, which is the same family as IDX, may have protective effects on normal tissues and organs in the field of radiation.”
Checkpoint inhibitors are the standard-of-care immuno-oncology drugs, but they have restricted benefit and are typically only effective in select cancers, such as lung cancer, melanoma or Hodgkin’s lymphoma, according to van Wyk.
“Only about 20 to 25 percent of patients with these cancer types respond to these drugs, so there is a great potential to provide benefit to a larger number of these patients,” van Wyk notes. “We are hopeful that IDX will prove effective in multiple cancer types.”
The global immune checkpoint inhibitor market currently includes PD-1, PD-L1 and CTLA4 inhibitors, van Wyk explains. Additional checkpoints have been discovered, and agents targeting these are in clinical development.
“With regards to our future immuno-oncology program, we would like to investigate Veyonda in combination with different checkpoint inhibitors, such as CTLA4 or PDA-1 inhibitors, in order to determine which regimen provides the most beneficial effects,” he says. “We hope to launch additional clinical studies in order to research this outcome.”
The company’s research program was prompted by evidence of abscopal (off-target) responses seen in patients being treated with a combination of Veyonda and radiotherapy, suggesting an immunological response.
“An abscopal response refers to the effect of radiotherapy on the tumors outside the field of radiation,” van Wyk notes. “The research referred to was from controlled animal experiments that demonstrated non-irradiated tumors on the alternate side of the body shrank considerably following the administration of Veyonda in combination with radiotherapy. We also have case reports of this effect having occurred in patients.”
“We remain committed to our plans to develop Veyonda in combination with chemotherapy, and also Veyonda in combination with radiotherapy, as both of these have shown a great deal of promise to date,” he says.
“The ultimate goal for Veyonda is to allow patients to live a longer, more fulfilling life,” van Wyk continues. “We aim to enable patients to enjoy more quality time with their loved ones. We remain committed to this mission and will work continuously to achieve this clinical goal in as many patients with as many different types of cancer as possible.”
The global immune checkpoint inhibitor market was valued at $10.5 billion in 2018, and is projected to reach $56 billion in 2025, the company reports. These figures are predicated on the use of these drugs in their current restricted manner. Lifting the response rate by even 10 percent above current use would represent a major breakthrough, leading to the research of additional cancer types which could expand the market considerably.