IRX Therapeutics is preparing to launch a Phase 3 clinical trial, the INSPIRE trial, to evaluate the safety and effectiveness of its investigational product, IRX-2, for the treatment of squamous cell head and neck cancer. Patients participating in the study will be newly diagnosed with advanced stage cancer and will be heading to surgery for removal of their cancer.

IRX Therapeutics has developed an information guide to provide a general overview of how the immune system works and how it can work in the battle against cancer. We hope that a better understanding of the immune system will give you a greater appreciation for the exciting scientific approach that IRX-2 represents and its potential to help cancer patients.

Normal cells in every individual contain a unique set of markers on their surfaces, which designate them as “self” and thus avoid attack by immune cells. In contrast, foreign invaders, diseased and damaged cells have different markers on their surfaces that enable immune cells to distinguish them as “non-self,” and to mount a response to target and eliminate them. The markers that trigger an immune response are called antigens. When “self” cells are infected by pathogens, they will produce “non-self” antigens as well, thereby signaling the immune system to attack.

The immune system’s foot-soldiers include different types of white blood cells that circulate throughout the body or reside in tissues. These cells play different roles in response to the presence of antigens. Important types of white blood cells include neutrophils, lymphocytes, monocytes, and dendritic cells, all of which are produced by bone marrow.

Lymphocytes that are processed in the thymus are called T cells, and among T cells there are different specialists. Some T cells, called killer T cells, destroy cells that have been infected by viruses and bacteria; they also help eliminate cancer cells that have not yet adapted to evade the immune system. Other T cells, serve as memory T cells that “remember” antigens after only one encounter, and sound the alert for other immune cells to respond when they recognize a foreign invader. Regulatory T cells (T regs), also known as suppressor T cells, work to inhibit the immune response.

There are millions of T cells circulating in the body at any given time, with only a relative few armed to detect a specific antigen. Once the antigen is encountered, however, these particular cells are recruited and multiply profusely, creating a massive army to confront the invader.

Cancer is a form of uncontrolled cell growth that can cause serious damage throughout the body. Cancer cells replicate at a highly accelerated rate, and often disable the mechanisms by which older cells are made to die off. The uncontrolled growth of cancer cells is accompanied by changes that enable them to come together as a tumor, reorganize the surrounding blood vessels to create their own blood supply, overwhelm neighboring tissues, and even invade distant tissues through the process of metastasis.

Cancer cells originate as “self” but as they convert from normal cells into cancer cells, they develop different antigens on their cell surfaces. These antigens can trigger immune cell activity, and indeed, the immune system is engaged in detecting and eliminating cancerous cells all the time. Despite the array of forces against them, cancer cells often survive and multiply, in part because tumors have clever defense mechanisms as well. In fact, cancer cells have a variety of ways in which they trick or even hijack the immune system to fend off attack.

Cancer cells can disguise their antigens so they escape detection. Scientists have discovered that tumors also can stimulate production of T reg cells, which suppress the immune response. The tumors surround themselves with these T reg cells, almost like a shield, to keep the body’s killer cells at bay. Tumors also send signals that trigger apoptosis (programmed cell death) in immune cells, killing them off in waves of cellular suicide.

One form of cancer in which a weakened immune system does seem to play a role is squamous cell carcinoma of the head and neck (H&NSCC). In addition, H&NSCC tumors produce a number of compounds that derail the normal activities of immune cells.

IRX Therapeutics has developed a novel product, IRX-2 that is designed to restore cellular immunity. It has already been in human clinical studies (Phase 1 and Phase 2) where IRX-2 was tolerated.

IRX-2 is designed to work by counteracting many of the measures H&NSCC tumors use to disrupt the immune system. IRX-2 is made up of several cytokines. These cytokines promote T cell development, stimulate dendritic cell maturation, and enhance monocyte function.

Patients in the Investigational arm of the INSPIRE trial will receive IRX-2 over a two-week period. The IRX-2 is given in the form of two injections just under the skin daily, one on each side of the neck just beneath the hairline. Overall, patients will receive 20 injections over 10 days. The needles used are small, and the shots are usually not painful. These patients will also receive several other medications and nutritional supplements, which are intended to create a favorable environment for IRX-2 to work. Together the combination of IRX-2 and the other medications and nutritional supplements make up the IRX-2 regimen.

It is hoped that the IRX-2 regimen may be able to immunize the patient against their tumor and thereby prevent or delay recurrence of the cancer after surgery. The INSPIRE trial is designed to determine whether or not IRX-2 has clinical benefit in Head and Neck cancer patients.

For the complete information guide, click here.