Tonix Pharmaceuticals Holding Corp. (Nasdaq: TNXP), a biopharmaceutical company with marketed products and a pipeline of development candidates, today announced the completion of the clinical stage of its Phase 1, single ascending dose escalation trial of TNX-1500 (Fc-modified humanized anti-CD40L monoclonal antibody, or mAb)* in healthy volunteers. TNX-1500 is in development for the prevention of rejection in solid organ and bone marrow transplant and for the treatment of autoimmune disorders.

“Despite advancements in the field of solid organ transplantation, there remains a significant need for new treatments with improved activity and tolerability,” said Seth Lederman, M.D., Chief Executive Officer of Tonix Pharmaceuticals. “Anti-CD40L modulates T cell function and has the potential to promote tolerance of transplanted organs. We are excited to have completed the clinical stage of this Phase 1 trial of TNX-1500, a third-generation Fc-modified anti-CD40L mAb that has been designed by protein engineering to eliminate the risk of thrombosis associated with first-generation anti-CD40L mAbs. Preclinical studies in non-human primates did not result in any thrombotic complications, suggesting that the protein engineering of TNX-1500’s Fc region has achieved its design goals.”

Dr. Lederman continued, “Recently, positive clinical data with other CD40L blockers have been reported by Sanofi, with its Fc-modified humanized anti-CD40L mAb frexalimab in treating relapsing multiple sclerosis.² Eledon Pharmaceuticals is developing tegoprubart, a non-covalent dimer antibody with no heavy-light or heavy-heavy interchain disulfide bridges for the prevention of rejection of kidney transplants³.”

Dr. Lederman concluded, “We believe TNX-1500 has the potential to prevent organ transplant rejection and improve graft survival with reduced long-term toxicity burden of current immunosuppressive regimens. In addition, TNX-1500 has the potential to address multiple other indications, including several autoimmune diseases. We look forward to the results of this Phase 1 trial, which are expected in the third quarter of this year, and to continuing the development of TNX-1500 as a promising candidate in an important therapeutic space.”