Genocea Biosciences, Inc. announced best-in-class clinical results from its ongoing Phase 1/2a trial for GEN-009, the company’s lead neoantigen vaccine candidate. In the five patients for whom immune response results are available to date, GEN-009 monotherapy elicited T cell responses to 91% of the vaccine neoantigens administered.

GEN-009 has proven to be unique among neoantigen vaccines in its ability to elicit ex vivo CD8⁺ T cell responses, which were observed for 47% of vaccine neoantigens. Inclusive of the results seen after in vitro stimulation, the CD8⁺ T cell response frequency was 53%. GEN-009 has been well tolerated to date, with no dose-limiting toxicities.

Dr. Roger Cohen, principal investigator commented, “I believe that these data could represent a breakthrough in the development of neoantigen vaccines. The Genocea data indicate that using the patients’ own T cells and antigen-presenting cells to select vaccine neoantigens results in higher immunogenicity than previously reported results using in silico methods. I look forward to investigating GEN-009 in combination with checkpoint inhibitors to explore whether this higher immunogenicity translates into greater clinical greater efficacy than seen with other neoantigen vaccines.”

Chip Clark, Genocea’s President & CEO, also commented: “These data clearly differentiate ATLAS, our neoantigen discovery platform, from first-generation, machine-based approaches. As we continue to say, “targets matter,” and these data highlight the necessity of selecting the right neoantigens to drive immune responses in cancer patients. We believe that ATLAS holds the potential to benefit the clinical efficacy of both GEN-009 and GEN-011, our neoantigen-specific T cell therapy program, and to enable additional immunotherapy modalities.”