Neoantigen vaccines represent a novel modality of cancer immunotherapy that targets the specific neoantigens present in an individual's cancer cells 1. These neoantigens, which are unique mutations not present in normal cells, serve as ideal targets for the immune system, thus providing a personalized approach to cancer treatment 2.
A clinical study (NCT03662815) was conducted to evaluate the antitumor effect of iNeo-Vac-P01, a personalized neoantigen vaccine, in the treatment of advanced solid tumor patients 3. The vaccine was designed and manufactured using an in-house bioinformatic pipeline analysis of whole-exome sequencing data obtained from tumor and peripheral blood cell DNA. The vaccine was administered subcutaneously, along with the adjuvant GM-CSF, to the study participants on days 1, 4, 8, 15, 22, 78, and 162, with additional immunizations given every 2-3 months based on individual patient benefit. The monotherapy of iNeo-Vac-P01 demonstrated safety and feasibility, with a disease control rate of 71.4%.
In a retrospective analysis, the study found a synergy between pre-vaccination radiofrequency ablation (RFA) and neoantigen vaccination 4. This finding was validated in an animal study where the concurrent therapy of RFA and neoantigen vaccination resulted in stronger antitumor responses compared to single modality alone, and the addition of anti-PD-1 further enhanced the antitumor effect.
In conclusion, the results of this study highlight the safety and feasibility of using iNeo-Vac-P01 as a monotherapy for the treatment of advanced solid tumors, and the potential for further improvement through the use of local RFA and systemic immunotherapy modalities.