A therapeutic cancer vaccine being co-developed by the Ludwig Institute for Cancer Research and the Australian biotech company CSL Limited successfully induced a comprehensive immune response in patients and appeared to delay cancer recurrence, according to a paper published today in the scientific journal, Proceedings of the National Academy of Sciences USA.
The study treated 46 patients, most with melanoma, with three monthly doses of the NY-ESO-1/ISCOMATRIXTM vaccine following surgical removal of the tumor. The vaccine combines a cancer-specific protein, the NY-ESO-1 antigen, with an immune stimulant, the ISCOMATRIXTM adjuvant, from CSL Ltd. In the study, some patients received different doses of the NY-ESO-1/ISCOMATRIXTM vaccine, some received the NY-ESO-1 protein without the ISCOMATRIXTM complex, and some received an inactive placebo. Detailed studies of the patients’ immune responses revealed that the NY-ESO-1/ISCOMATRIXTM vaccine, in contrast to vaccination with the placebo, induced the production of antibodies, and CD8 and CD4 T cells that target the NY-ESO-1 antigen. Vaccination with the NY-ESO-1 protein alone induced fewer responses than the NY-ESO-1/ISCOMATRIXTM vaccine.
“These results are very exciting,” says Dr. Jonathan Cebon, Head of the Joint Austin Health/Ludwig Institute Oncology Unit in Melbourne. “They show that it is possible to stimulate an integrated immune response that has the potential to attack cancer from a number of different angles. Being able to get antibodies, together with both types of T cells, gives us enormous confidence that we are heading in the right direction to develop a clinically effective therapy.”