Genocea Presents Follow-up Data from GEN-009 Neoantigen Vaccine Phase 1/2a Trial at ESMO Virtual Congress 2020

Step-down responses to GEN-009, with 3 objective responses (2 PR, 1 CR) in the first 5 patients, suggests added benefit to PD-1 inhibitor therapy

100% of patients have immune responses to ATLAS-identified neoantigens

CAMBRIDGE, Mass., Sept. 17, 2020 (GLOBE NEWSWIRE) -- Genocea Biosciences, Inc. (NASDAQ: GNCA), a biopharmaceutical company developing next-generation neoantigen immunotherapies, today presents additional clinical response and immunogenicity data from the first five patients vaccinated in Part B of the ongoing GEN-009 Phase 1/2a trial at the European Society for Medical Oncology (ESMO) Virtual Congress 2020.

ESMO E-POSTER PRESENTATION:
Poster 1028P 
Title: Preliminary results of a pilot trial of GEN-009, a neoantigen vaccine containing immunogenic tumor specific neoantigens, in combination with PD-1 inhibitors in advanced cancers
Date: September 17, 2020
Time: at 9:00 a.m. CEST (3:00 a.m. EDT)
Link to the poster: https://www.esmo.org/meetings/esmo-virtual-congress-2020/registration?hit=ehp

The results build on the Part B findings shared previously, which evaluated the preliminary immunogenicity and efficacy of GEN-009 in combination with standard-of-care checkpoint inhibitor-based regimens (CPI) in an initial cohort of five patients with advanced solid tumors. All five patients received GEN-009 approximately four months following the start of CPI treatment.

New follow-up scans, ranging from 91-233 days post-vaccination, confirm the previously disclosed findings, with tumor reduction or stable outcomes for all five patients, including three RECIST-criteria changes in tumor size (2 PR, 1 CR) after vaccination and likely attributable to GEN-009. The new results continue to suggest GEN-009 vaccination could be used in conjunction with CPI-based therapies to augment their effects. In addition, 100 percent of patients had neoantigen-specific responses elicited by vaccination, in some cases with evidence of epitope spread. No significant adverse side effects were reported, with only mild symptoms associated with the vaccine adjuvant.

“The step-down response curves represent a promising and previously unobserved pattern of tumor response that warrants further investigation,” said Maura Gillison, M.D., Ph.D., Professor of Medicine, Department of Thoracic/Head and Neck Medical Oncology at MD Anderson Cancer Center. “It will be important to continue our assessment of GEN-009’s specific contribution to the clinical effects seen to date. We look forward to validating these results in a broader cohort to support our hypothesis that inclusion of GEN-009 in CPI regimens may lead to beneficial outcomes for patients with hard-to-treat solid cancers.”