Vaxille Verages unique approach to immune therapy in fight against cancer
Medical teams are waging the war on cancer on hundreds of battlefronts, but occasionally one approach developed for that fight shows unusual promise.
A case in point is immunotherapy, which has the potential to be the most important cancer breakthrough since the advent of chemotherapy.
While the human immune system can recognize and fight foreign substances, it’s not as capable of recognizing certain cancer cells. Immunotherapy’s goal is to change that, by helping and training the body’s own immune responders, T cells, to recognize and attack cancer.
To date, the U.S. Food and Drug Administration has approved more than a dozen immunotherapies for an array of cancer types, and the list of cancers being targeted by immunotherapy keeps growing.
Some analysts estimate that immunotherapy treatments could be treating more than half of cancers within a decade.
One promising weapon in the immunotherapy arsenal is ImMucin, a treatment that’s been developed over the past 10 years by Canadian-Israeli immunotherapy biotech Vaxil Bio Ltd. ( TSX.V: VXL).
Using its proprietary Vaxhit platform algorithm, Vaxil researchers first identify candidate peptides— chains of amino acids—present on the cancer cells, which can serve as targets to the immune system. Once those are identified, the company’s researchers test and validate them as potential antigens to trigger the body’s immune system and train T cells to attack them, thereby disrupting the cancer cells.
“Vaxil is pioneering a novel approach to cancer treatment within the rapidly prevailing immunotherapy landscape,” says Isaac Maresky, executive director of the board at Vaxil Bio Ltd. “Our objective is to become the worldwide experts when it comes to signal peptides as neoantigen immunotherapies, a specialization which Vaxil has developed over many years of R&D.”
He notes that Vaxil’s approach is also different from other current cancer immunotherapy approaches. These include anti–immune checkpoint inhibitors, drugs that release the molecular breaks built into the T-cells, thus unleashing their full potential, and CAR-Ts, which re-engineer the patient’s own T cells to attack cancer.
“We’re spearheading research in an exciting new field known as cancer neoantigens,” says Dr. Limor Chen, vice-president of operations and clinical affairs at Vaxil’s laboratory at the Weizmann Science Park in Rehovot, Israel. “Other modalities target traditional parts of mutated cancer antigens hoping to evoke a significant and long-lasting immune response against them. We are focusing on a totally different domain of these antigens, which holds the potential to elicit a much stronger response and frustrate the mechanism of cancer cells to evade immune surveillance. This discovery was a true surprise to us.”
The antigen MUC1 was selected as Vaxil’s current target because it’s a marker found in 90 per cent of all cancers. In fact, the U. S. National Cancer Institute identified MUC1 as the second most promising target from its list of 75 prioritized tumour-associated antigens.
ImMucin completed a Phase I/ II Clinical Trial in 2012. It was used in the treatment of 15 patients with multiple myeloma, a rare form of blood cancer affecting plasma cells, which are responsible for producing antibodies.
“We selected multiple myeloma for our pilot study because it remains an unmet medical need and we were able to closely trace and monitor clinical results,” says Dr. Saeid Babaei, a University of Toronto-trained scientist and chairman of Vaxil. “Additionally, it enabled Vaxil to initiate its proof of concept in cancer patients having a high expression of MUC1 on affected plasma cells.”
A paper prepared by Vaxil researchers on this study, and published in the April 2015 British Journal of Hematology, reported “a broad and robust immunological response from 100% of the patients.” Of the 15 patients involved in the study, the researchers reported that 11 demonstrated either remission or stable disease that did not require further treatment at that time.
“While results have been promising on a number of fronts, Vaxil has been constrained by the financial resources of being a small company,” says Maresky. “It’s our responsibility to do whatever it takes to advance our treatment further, always with the ultimate end goal in mind: helping as many patients as possible.”
In further trials, Vaxil researchers hope to test larger numbers of patients presenting with other MUC1-positive cancers, possibly including breast, lung and ovarian cancer. Vaxil has already made initial preparations for the production of its next clinical batch and will then seek FDA approval for an upcoming clinical trial.
“ImMucin is a unique and distinct approach to fighting cancer not offered by other immunotherapies,” says Dr. Chen. “And I truly believe it holds promise for many kinds of cancers.”