ImmunityBio announced that enrollment and initial follow-up has been completed for the safety portions of a clinical trial that is studying ImmunityBio's investigational cancer vaccine of a tri-valent combination of antigens delivered by a second-generation Adenovirus vector (Tri-Ad5 CEA/MUC1/brachyury) together with its IL-15 superagonist N-803 for participants with Lynch syndrome. The study, sponsored by the National Cancer Institute, part of the National Institutes of Health, will include up to 186 participants when fully enrolled and is now open to the randomized controlled portion of the trial. Each of the three vaccines in Tri-Ad5 targets different proteins associated with precancer and cancer cells.

The vaccine combination is studying whether activation of dendritic cells and training the immune system to recognize those proteins will destroy the precancer cells before the cancer occurs. The IL-15 superagonist N-803 is designed to enhance the effects of the vaccines by increasing proliferation and activation of natural killer (NK) and T cells, thereby increasing the potential for cancer prevention in study participants. Lynch syndrome (also called hereditary non-polyposis colorectal cancer or HNPCC) is one of the most common hereditary cancer syndromes occurring in 1 in every 300 Americans.2 Not only can people with Lynch syndrome develop colorectal cancer 20 years before the average age of diagnosis for this cancer, they are also at an increased risk of developing multiple types of other cancers, including endometrial, stomach, ovarian, pancreas, ureter and renal pelvis, biliary tract, brain, and small intestinal cancers.

Colorectal cancer is the second-deadliest cancer type in the U.S., and approximately 3% to 5% of the 153,000 cases of colorectal cancer annually are thought to be due to Lynch Syndrome, as are 2% to 3% of all cases of endometrial cancer. ImmunityBio?s Tri-Ad5 Vaccines and N-803 are investigational. Safety and efficacy of these investigational agents have not been established by any Health Authority, including the FDA.