Abstract 150P
Background
HER2/neu is overexpressed in 15% - 25% of gastric cancers. IMU-131 is a B-cell peptide vaccine composed of 3 epitopes of the extracellular domain of HER2/neu. Antibodies against IMU-131 peptides elicit antitumor activity in vitro and a phase I study demonstrated safety and immunogenicity in Her-2 +/ ++ breast cancer patients.
Methods
IMU-131 was given to patients with HER2/neu positive gastric cancer in an open-label phase 1b dose escalation trial with 14 Asian and Eastern European sites. Each patient received IMU-131 on Days 0, 14, and 35, with cisplatin and 5-fluorouracil or capecitabine every 21 days. Patients remained on study until disease progression. Ongoing patients received boosters at D98 then every 84 days.
Results
14 patients were enrolled with 10 HER2 overexpressing (7 x HER2 +++, 3 x HER2 ++ FISH positive) and 4 HER2 ++ expressing tumors. Mean age was 57 yo (range of 21 - 79) with ECOG scores of 0 or 1 in 7 patients each. There were 9 Asian and 5 Caucasian patients with 5 females and 9 males. Dose levels were 10, 30 and 50 µg with 3, 6, and 5 patients respectively. 11 patients received all 3 doses and 3 patients received only 2 doses due to disease progression. P467 and HER2 antibodies were generated at all dose levels with patients dosed at 50µg responding to the vaccine with equally high antibody levels. There were no DLTs or SAEs related to IMU-131. Of the 14 patients dosed 11 were evaluable for tumor progression at day 56 and later. Of those patients, the best response was 1 CR, 5 PR, 4 SD and 1 PD. Two patients, both dosed at 50µg IMU-131, remain on study after D266, with one patient’s tumor reduced by approximately 80% from 177mm at baseline to 37mm at D266.
Conclusions
Safety data indicate that IMU-131 is well tolerated with no significant local or systemic reactions. There were no dose-limiting toxicities observed, no significant injection site reactions and no IMU-131 related SAEs. The 50µg dose produced the most consistent P467 and HER-2 specific antibodies compared to 10 and 30µg doses with preliminary response data demonstrating 50µg of IMU-131 is associated with tumor size reduction. The 50µg dose of IMU-131 is being used in the phase 2 study.
Clinical trial identification
Identifier: NCT02795988.
Editorial acknowledgement
Legal entity responsible for the study
Imugene Ltd.
Funding
Imugene Ltd.
Disclosure
N. Ede: Full / Part-time employment: Imugene. L. Chong: Full / Part-time employment, Officer / Board of Directors: Imugene. A. Good: Full / Part-time employment: Imugene. All other authors have declared no conflicts of interest.
Resources from the same session
511P - Phase II trial of carboplatin, nab-paclitaxel and bevacizumab for advanced non-squamous non-small cell lung cancer (CARNAVAL study; TORG1424/OLCSG1402)
Presenter: Toshio Kubo
Session: Poster display session
Resources:
Abstract
485P - A real-world experience of first-line afatinib in Korean patients with EGFR-mutant non-small cell lung cancer
Presenter: Seong Hoon Yoon
Session: Poster display session
Resources:
Abstract
522P - Weekly nab-PTX and weekly PTX for relapsed small cell lung cancer
Presenter: Hajime Oi
Session: Poster display session
Resources:
Abstract
512P - A phase I and extension study of S-1 and carboplatin for previously untreated patients aged 75 years or more with advanced non-small cell lung cancer
Presenter: Hisao Imai
Session: Poster display session
Resources:
Abstract
497P - Real-word efficacy of osimertinib in patients with metastatic EGFRm NSCLC: An interim analysis from a multi-center study in China
Presenter: Xiangyun Ye
Session: Poster display session
Resources:
Abstract
507P - Immune checkpoint inhibitors for patients acquired resistance to tyrosine kinase inhibitors with EGFR mutated non-small cell lung cancer: A multicenter retrospective study
Presenter: Takeshi Uenami
Session: Poster display session
Resources:
Abstract
516P - Clinical outcomes in elderly patients with advanced non-small cell lung cancer: A prospective multicenter study of the National Hospital Organization in Japan
Presenter: Masahiro Shimada
Session: Poster display session
Resources:
Abstract
486P - Phase II study of low-dose afatinib maintenance treatment for patients with EGFR-mutated non-small cell lung cancer (NJLCG1601)
Presenter: Mami Morita
Session: Poster display session
Resources:
Abstract
515P - Polypharmacy as a prognostic factor in elderly patients with advanced non-small cell lung cancer treated with immune checkpoint inhibitors
Presenter: Taiki Hakozaki
Session: Poster display session
Resources:
Abstract
518P - Real world prospective clinical impact of finding actionable genomic alterations by plasma cell-free DNA next generation sequencing in advanced non-small cell lung cancer
Presenter: Beung chul Ahn
Session: Poster display session
Resources:
Abstract