Nexvax2® belongs to an emerging class of therapeutic vaccines based on the same principles as "traditional" desensitization therapy for allergic conditions that restore long-term tolerance to allergens (ref. 1,2). Peptide-based therapeutic vaccines have been successful in preventing and treating immune diseases in the laboratory. Major international programs are underway to discover and develop peptide-based therapeutic vaccines for multiple sclerosis, type 1 diabetes, rheumatoid arthritis, and other autoimmune diseases, as well as various allergic diseases including cat-sensitive asthma (ref. 3).
Nexvax2® is the only disease-modifying therapeutic approach for celiac disease in clinical development today that has the potential to enable patients to return to a normal diet, good health, and improved quality of life. Nexvax2® is a combination of three proprietary peptides that elicit an immune response in patients with celiac disease (CeD) who carry the immune recognition gene, HLA-DQ2.5, which accounts for the condition in 80% to 90% of patients. Nexvax2® is delivered intradermally as a therapeutic vaccine and reprograms the T-cells that respond to gluten antigens in CeD patients so that they stop responding defensively by triggering a pro-inflammatory response. As a result, by preventing T-cells from continuing to cause inflammation in the small intestine, the injured tissue heals and patients would be able to resume an unrestricted diet and enjoy improved health. Booster shots of Nexvax2® would offer periodic reinforcements of the treatment to establish a prolonged tolerance to gluten.
ImmusanT has recently completed two Phase 1b safety, tolerability, and pharmacodynamics clinical trials, which provided unprecedented data supporting proof-of-mechanism and effectiveness. Specifically, Nexvax2® was found to engage antigen-specific target cells, and a distinct immunological signature was discovered. After repeated dosing, patients who received Nexvax2® were able to complete gluten challenge in contrast to placebo.
For more information on Nexvax2 therapy, please refer to the ImmusanT Nexvax2® Fact Sheet.
Compared to the current definitive diagnostic tool of a small bowel biopsy, an invasive procedure which is prone to sampling error and other drawbacks, ImmusanT’s in vitro Nexvax2® blood tests are designed to measure T-cell activity through a simple, whole blood cytokine release test. Nexvax2® diagnostics would provide patients with a non-invasive alternative that could lead to more rapid and accurate diagnosis of celiac disease. The introduction of non-invasive, personalized diagnostics, together with growing awareness of the disease, is expected to not only lead to increased diagnosis of patients with celiac disease, but also enable identification of patients who would respond to Nexvax2 and monitor their immune response to gluten. The diagnostics could also help distinguish celiac disease, a condition defined by inflammatory injury of the gut, from related manifestations such as non-celiac gluten sensitivity.
Diagnostic tests measuring antigen-specific T-cells are already in clinical practice to aid in the diagnosis of other conditions, such as the interferon-gamma release tests to identify an immune reaction to bacterial antigens that cause tuberculosis. ImmusanT’s diagnostic program includes development of three major diagnostic tools to detect and characterize gluten-reactive T cells in celiac disease by measuring cytokines released in blood incubated with gluten peptides, cytokines in blood from individuals treated with Nexvax2, and using MHC-peptide multimers (collaboration with Professor Sollid’s Laboratory, University of Oslo).