Celldex Therapeutics, Inc. (NASDAQ: CLDX) today announced that the Company presented initial clinical data on CDX-1401 at the 25th Annual Meeting of the International Society of Biological Therapy of Cancer (iSBTc) in Washington, DC. CDX-1401 is a novel antibody-based targeted cancer vaccine candidate being evaluated as a treatment for patients with melanoma and other cancers that are known to express the tumor antigen NY-ESO-1.
“The initial data from this ongoing study confirm safety and immunogenicity even in patients with advanced cancer who have received multiple prior therapies. CDX-1401 has passed the initial Phase 1 hurdles and we look forward to forthcoming cohorts that will include additional TLR agonists in combination regimens.”
The data presented were from a Phase 1/2 dose-escalating clinical trial evaluating three different doses of the vaccine in combination with resiquimod , which is an activator of toll-like receptors 7 and 8 (TLR7/8) and stimulator of immune cells. The study has enrolled 20 patients with advanced cancer, of which 35% had confirmed NY-ESO-1 expression. Six patients maintained stable disease and were eligible for multiple cycles of the treatment regimen, including 4 patients who have received 3 or more cycles (6 weeks of treatment followed by a 6 week rest), with stable disease of up to 11.5+ months. The treatment was well tolerated and there were no dose-limiting toxicities. Robust anti-NY-ESO-1 immunity was induced with the majority of the patients developing anti-NY-ESO-1 antibody responses and 39% of the patients having increases in NY-ESO-1 specific T cell responses, including both CD4 and CD8 responses. Importantly, the T cell responses were directed against multiple regions of the NY-ESO-1 antigen.
"CDX-1401 represents a new generation of off-the-shelf dendritic cell targeted vaccines built upon excellent preclinical activity data," said Tom Davis, M.D., Chief Medical Officer of Celldex Therapeutics. "The initial data from this ongoing study confirm safety and immunogenicity even in patients with advanced cancer who have received multiple prior therapies. CDX-1401 has passed the initial Phase 1 hurdles and we look forward to forthcoming cohorts that will include additional TLR agonists in combination regimens."
The CDX-1401 study is continuing to enroll patients to additional cohorts that include combination with poly-ICLC (Hiltonol™), a potent TLR3 agonist and stimulator of immune cells. The study is currently being conducted at multiple centers including Yale Cancer Center, Henry Ford Hospital and Medical Group, Memorial Sloan Kettering Cancer Center, and Weill Cornell Medical College.