Abstract 5780
Background
Anti-PD-1 blocking monoclonal antibodies (mAbs) such as nivolumab or pembrolizumab have shown potent anti-tumor effects in different metastatic cancers. Similarly, anti-HER-2 mAbs such as Herceptin and Perjeta are approved for breast cancer. These mAbs are only effective in 10-25% of cancer patients, and are limited by high costs, side effects and development of resistance. Contrary to treatment with monoclonal antibodies, chimeric B-cell cancer vaccines incorporating a “promiscuous” T cell epitope have the advantage of safer and cheaper alternatives, producing a specific immune response that induces memory B & T cell responses, while reducing immune evasion, suppression and resistance.
Methods
We have translated two HER-2 combination peptide vaccines (B-Vaxx) to the clinic in a Phase 1/2b trial to safely deliver curative and transformative cancer immunotherapies to advanced cancer patients. We have created and established the development of a novel B-cell peptide vaccine (Key-Vaxx) with high immunogenicity that binds to human PD-1 and produces tumor inhibition in vivo in two animal models of colon cancer. We will describe the CT-26, CT26-HER2 and MC38 tumor models in Balb/c and C57/Bl6 used to test for synergistic effects of anti-PD1 immunization therapy in combination with anti-HER2 immunization therapy. The immunogenicity/optimal immunologic dose and toxicity profile was investigated in beagle dogs.
Results
We show robust HER-2 and PD-1 antibody responses in mice, beagle dogs and non-human primates. The individual (PD-1) or combined vaccination (B-Vaxx)) was effective in reducing tumor growth in a Balb/c and C57Bl/6 syngeneic model of colon carcinoma and exhibited superior activity compared to the positive gold control anti-mouse PD-1 (CD279) monoclonal antibody.
Conclusions
Development of PD-1 B-cell vaccine was successful, showing no evidence of toxicity or autoimmunity in mice, rabbits and beagle dogs. The combination vaccines could provide improved outcomes in early stage disease sparing patients the toxicity of chemotherapy. A phase 1 clinical trial with the PD-1 vaccine is under planning.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
The authors.
Funding
NIH; Imugene.
Disclosure
All authors have declared no conflicts of interest.
Resources from the same session
1707 - Clinical utility of precision immunoprofiling and monitoring of the tumor microenvironment using flow cytometry and CyTOF in patients with advanced NSCLC treated with atezolizumab: results from a phase II study for biomarker analysis (EPOC1702)
Presenter: Keisuke Kirita
Session: Poster Display session 3
Resources:
Abstract
3594 - Tumor mutation burden (TMB), PD-L1, IFN-γ signaling identify subgroups of patients (pts) who benefit from durvalumab (D, anti-PDL1) or D and tremelimumab (T, anti-CTLA4) treatment in urothelial bladder cancer (UC)
Presenter: Christophe Massard
Session: Poster Display session 3
Resources:
Abstract
744 - The decrease of TMB, TNB and HLA expression are the Mechanism of Drug Resistance of NSCLC to immunosuppressive PD-1/PD-l1.
Presenter: Sheng Yu
Session: Poster Display session 3
Resources:
Abstract
2350 - Eosinophilia during treatment of immune checkpoint inhibitors (ICIs) predicts succeeding onset of immune-related adverse events (irAEs)
Presenter: Rika Kizawa
Session: Poster Display session 3
Resources:
Abstract
5930 - A transcriptomic immunologic signature predicts favorable outcome in neoadjuvant chemotherapy treated triple negative breast tumors.
Presenter: Javier Pérez-peña
Session: Poster Display session 3
Resources:
Abstract
6127 - Alterations of TMB and TCR repertoires during Chemotherapy in East Asian lung cancer patients without TKI-related driver gene mutations
Presenter: Lele Song
Session: Poster Display session 3
Resources:
Abstract
1310 - Association of SCFA in gut microbiome and clinical response in solid cancer patients treated with andi-PD-1 antibody.
Presenter: Motoo Nomura
Session: Poster Display session 3
Resources:
Abstract
2286 - Extracellular matrix and tissue derived metabolites in a liquid biopsy identifies endotypes of metastatic melanoma patients with differential response to immune checkpoint inhibitor treatment
Presenter: Nicholas Willumsen
Session: Poster Display session 3
Resources:
Abstract
4107 - Pathologic scoring of pre-treatment H&E biopsies predicts overall survival in patients with metastatic clear cell renal cell carcinoma receiving nivolumab monotherapy
Presenter: Julie Stein
Session: Poster Display session 3
Resources:
Abstract
1291 - PD-L1 expression in uncommon EGFR-mutant non-small cell lung cancer and its response to immunotherapy
Presenter: Yun Fan
Session: Poster Display session 3
Resources:
Abstract