Abstract 5043
Background
HER2/neu is overexpressed in 15-25% of gastric cancer patients and associated with poor prognosis. Treatment with recombinant monoclonal Abs against HER2/neu is effective yet alternatives are needed due to cost and global availability issues. Thus a peptide vaccine (IMU-131) was developed, consisting of 3 fused B-cell epitopes (p467) from the HER2/neu extracellular domain coupled to CRM197 and administered with the adjuvant Montanide. The present study evaluated the optimal/safe vaccine dose leading to immunogenicity and clinical responses.
Methods
In an open-label multicenter Phase Ib trial (SE-Asia & Eastern Europe), 14 patients with HER2/neu overexpressing ( ++/ +++) gastric adenocarcinoma were recruited to receive 3 injections of IMU-131 (days 0, 14, 35) in combination with chemotherapy (CT). Dose escalation (10, 30 and 50 µg) was performed in 3 cohorts (C) to evaluate safety, immunogenicity and clinical responses.
Results
No SAEs related to IMU-131 administration were reported. Eleven patients were evaluable for vaccine-specific immune responses and RECIST assessment. Higher HER2-specific IgG levels were observed in C2 (30 µg) vs. C1 (10 µg). 3/5 patients in C2 showed moderate or little increase in HER2-specific Abs, while all C3 patients (50µg) responded with moderate to high Ab levels. According to RECIST, 1 patient showed complete response, 5 partial response and 4 stable disease. Strong correlation between high Ab levels and clinical responses was observed in C3, while this was only moderate in C2. Capacity to inhibit HER2 phosphorylation was tested in patient sera and could be detected in association with strong tumor reduction. Furthermore, patients with good clinical responses, but low Ab titers featured cellular responses with high IFNγ and TNFα/IL-10 ratios.
Conclusions
The vaccine was well tolerated and safe with Ab responses at the highest dose showing strong correlation with clinical responses. Currently, the 50 µg dose is being evaluated in a Phase II trial with two arms (IMU 131 + CT and CT only).
Clinical trial identification
NCT02795988.
Editorial acknowledgement
Legal entity responsible for the study
Imugene Ltd.
Funding
Imugene Ltd.
Disclosure
U. Wiedermann: Research grant / Funding (institution), Officer / Board of Directors, CSO until September 2018: Imugene; Research grant / Funding (institution): GSK; Research grant / Funding (institution): Pfizer; Research grant / Funding (institution): Themis. I. Bulat: Advisory / Consultancy, Research grant / Funding (self), Full / Part-time employment: Arensia Exploratory Medicine . T. Yau: Honoraria (self), Advisory / Consultancy: Bristol-Myers Squibb. M. Maglakelidzde: Advisory / Consultancy, Research grant / Funding (self), Full / Part-time employment: ARENSIA Exploratory Medicine . T. Ungtrakul: Travel / Accommodation / Expenses: AstraZeneca. C.C. Zielinski: Honoraria (self), Advisory / Consultancy: Roche; Honoraria (self), Advisory / Consultancy: Novartis; Honoraria (self), Advisory / Consultancy, Research grant / Funding (institution): BMS; Honoraria (self), Advisory / Consultancy, Research grant / Funding (institution): MSD; Honoraria (self), Advisory / Consultancy, Officer / Board of Directors, Scientific Advisory Board Member until June 2018: Imugene; Honoraria (self), Advisory / Consultancy: Ariad; Honoraria (self), Advisory / Consultancy, Research grant / Funding (institution): Pfizer; Honoraria (self), Advisory / Consultancy: Merrimack; Honoraria (self), Advisory / Consultancy: Merck; Honoraria (self), Advisory / Consultancy: KGaA; Honoraria (self), Advisory / Consultancy: Fibrogen; Honoraria (self), Advisory / Consultancy, Research grant / Funding (institution): AstraZeneca; Honoraria (self), Advisory / Consultancy: Tesaro; Honoraria (self), Advisory / Consultancy: Gilead; Honoraria (self), Advisory / Consultancy: Servier; Honoraria (self), Advisory / Consultancy: Shire; Honoraria (self), Advisory / Consultancy: Eli Lilly; Honoraria (self), Advisory / Consultancy: Athenex. L. Chong: Honoraria (self), Advisory / Consultancy, Leadership role, Travel / Accommodation / Expenses, Shareholder / Stockholder / Stock options, Full / Part-time employment: Imugene Ltd. N. Ede: Leadership role, Research grant / Funding (institution), Travel / Accommodation / Expenses, Shareholder / Stockholder / Stock options, Licensing / Royalties, Full / Part-time employment: Imugene Ltd. A. Good: Advisory / Consultancy, Leadership role, Shareholder / Stockholder / Stock options, Full / Part-time employment: Imugene Ltd; Advisory / Consultancy, Shareholder / Stockholder / Stock options: Kazia Therapeutics; Shareholder / Stockholder / Stock options: Living Cell Technologies. All other authors have declared no conflicts of interest.
Resources from the same session
2316 - A 3D co-culture platform of breast cancer and patient derived immune cells to analyse the response to chemotherapy and immunotherapies
Presenter: Diana Saraiva
Session: Poster Display session 3
Resources:
Abstract
4290 - Characterization of the mechanism of action and efficacy of MEN1611 (PA799), a novel PI3K inhibitor, in breast cancer preclinical models.
Presenter: Alessio Fiascarelli
Session: Poster Display session 3
Resources:
Abstract
2167 - Neat-1: culprit lnRNA tying PIG-C, MSLN, CD80 in TNBC
Presenter: Nada Hussein
Session: Poster Display session 3
Resources:
Abstract
1829 - A novel RAF/MEK inhibitor CH5126766 in phase 1 clinical trial has an effectiveness in the combination with eribulin for the treatment of triple negative breast cancer
Presenter: Hisako Ono
Session: Poster Display session 3
Resources:
Abstract
4357 - Identification of a stemness-related gene panel associated with BET inhibition in triple negative breast cancer
Presenter: Eva Galan-Moya
Session: Poster Display session 3
Resources:
Abstract
5163 - Preclinical Evaluation targeting both IGF1R and IR in Triple Negative Breast Cancer
Presenter: Alex Eustace
Session: Poster Display session 3
Resources:
Abstract
832 - Monospecific antibody targeting of CDH11 inhibits epithelial-to-mesenchymal transition and represses cancer stem cell-like phenotype by up-regulating miR-335 in metastatic breast cancer, in vitro and in vivo.
Presenter: Jia-Hong Chen
Session: Poster Display session 3
Resources:
Abstract
3781 - Pharmacological screening with Chk1 inhibitors identify synergistic agents to overcome resistance to platinums in basal breast and ovarian cancer
Presenter: Ana Lucia Sanabria
Session: Poster Display session 3
Resources:
Abstract
3275 - Comparison of 11 circulating miRNAs and CA125 kinetics in ovarian cancer during first line treatment: data from the randomized CHIVA trial (a GINECO-GCIG study)
Presenter: Patrick Robelin
Session: Poster Display session 3
Resources:
Abstract
3391 - Inhibiting Ehmt2 and Ezh2 histone methyltransferases alters the immune microenvironment in a Trp53-/- murine ovarian cancer model
Presenter: Pavlina Spiliopoulou
Session: Poster Display session 3
Resources:
Abstract