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
5389 - Two-weekly accelerated BEP (aBEP) regimen as induction chemotherapy (CT) in intermediate and poor prognosis patients (pts) with nonseminomatous germ cell tumors (NSGCT): final results of phase II trial.
Presenter: Alexey Tryakin
Session: Poster Display session 3
Resources:
Abstract
2934 - Differential expression of circulating miR375 and miR371 to detect teratoma and viable germ cell malignancy
Presenter: Lucia Nappi
Session: Poster Display session 3
Resources:
Abstract
3585 - Prognosis of anaemia in disseminated testicular germ cell tumours. On behalf of the Spanish Germ Cell Cancer Group (SGCCG)
Presenter: Esmeralda Garcia Torralba
Session: Poster Display session 3
Resources:
Abstract
2254 - The Effects Of Primary Testicular Tumor Localization On Prognosis In Patients With Nonseminomatous Testis Cancer
Presenter: Birol Yildiz
Session: Poster Display session 3
Resources:
Abstract
4505 - Initial Results of a Phase II study of Nivolumab and Ipilimumab in Metastatic Adrenal Tumors.
Presenter: Matthew Campbell
Session: Poster Display session 3
Resources:
Abstract
3369 - NEMIO: a randomized phase II trial evaluating efficacy and safety of dose dense MVAC (ddMVAC) + durvalumab +/- tremelimumab as neoadjuvant treatment in patients with bladder muscle-invasive urothelial carcinoma
Presenter: Constance Thibault
Session: Poster Display session 3
Resources:
Abstract
2075 - KEYNOTE-866: Phase 3 Study of Perioperative Pembrolizumab (pembro) or Placebo (pbo) in Combination With Neoadjuvant Chemotherapy in Cisplatin (cis)-Eligible Patients (pts) With Muscle-Invasive Bladder Cancer (MIBC)
Presenter: Arlene Siefker-Radtke
Session: Poster Display session 3
Resources:
Abstract
4824 - KEYNOTE-905: A Phase 3 Study of Cystectomy Plus Perioperative Pembrolizumab Versus Cystectomy Alone in Cisplatin (cis)-Ineligible Patients (pts) With Muscle-Invasive Bladder Cancer (MIBC)
Presenter: Matthew Galsky
Session: Poster Display session 3
Resources:
Abstract
2253 - Phase 3 LEAP-011 trial: First-Line Pembrolizumab With Lenvatinib in Patients With Advanced Urothelial Carcinoma Ineligible to Receive Platinum-Based Chemotherapy
Presenter: Yohann Loriot
Session: Poster Display session 3
Resources:
Abstract
4310 - PULSE : A Single Arm Trial Assessing The Activity and Safety of Avelumab Immunotherapy Maintenance among Patients With Locally Advanced or Metastatic Squamous Cell Penile Carcinoma (mSCPC).
Presenter: Noemie Gassian
Session: Poster Display session 3
Resources:
Abstract