ExpreS2ion Biotechnologies has announced the approval of its Phase I clinical trial application (CTA) by the Austrian Agency for Health and Food Safety for ES2B-C001, a novel therapeutic vaccine targeting HER2-expressing breast cancer. The trial marks ExpreS2ion's first clinical-stage development project, with dosing of the first patient expected to commence shortly.
Preclinical Efficacy
ES2B-C001 has demonstrated promising preclinical results, showing significant inhibition of human breast cancer tumor growth and achieving 100% survival in mouse models when used both prophylactically and therapeutically. According to Dr. Farshad Guirakhoo, Chief Science Officer, sera from vaccinated mice effectively blocked colony formation by human breast cancer cells, including those resistant to Herceptin. These findings suggest ES2B-C001's potential to overcome resistance to current immunotherapies and improve outcomes for patients with HER2-expressing cancers.
Trial Design and Objectives
The open-label, dose-escalation Phase I trial will evaluate the safety, tolerability, and maximum tolerated dose (MTD) of ES2B-C001, administered either alone or in combination with the adjuvant Montanide. The study plans to enroll up to 30 patients with metastatic breast cancer.
ES2B-C001 Mechanism of Action
ES2B-C001 is a first-in-class therapeutic vaccine that utilizes virus-like particles (VLPs) to display the full extracellular domain of the human HER2 protein on its surface. This approach aims to stimulate a robust and durable polyclonal immune response against HER2-expressing tumor cells. The VLP platform underpinning ES2B-C001 has been previously validated in a Phase III pivotal trial for Bavarian Nordic's ABNCoV2 COVID-19 vaccine, demonstrating its safety and tolerability in over 4,000 participants.
About HER2-Expressing Breast Cancer
HER2 (Human Epidermal Growth Factor Receptor 2) is a protein that promotes cell growth. In about 20% of breast cancers, the HER2 gene is amplified, leading to an overproduction of the HER2 protein. This type of breast cancer tends to be more aggressive. Current treatments for HER2-positive breast cancer include targeted therapies like Herceptin (trastuzumab), but resistance can develop, highlighting the need for new therapeutic strategies.
Executive Commentary
Bent U. Frandsen, Chief Executive Officer of ExpreS2ion, expressed enthusiasm for reaching this milestone, stating, "ES2B-C001 is a promising vaccine candidate with the potential to address multiple severe cancer indications, from breast cancer to gastro-oesophageal cancer."
