ExpreS2ion announces further positive preclinical proof-of-concept results for the HER2-cVLP breast cancer vaccine

Report this content

Hørsholm, Denmark, January 4, 2022 – ExpreS2ion Biotech Holding AB’s affiliate ExpreS2ion Biotechnologies ApS (“ExpreS2ion") announces that the capsid virus-like particle (cVLP) HER2-breast cancer vaccine candidate ES2B-C001 has demonstrated proof-of-concept also in HER2-transgenic preventive as well as therapeutic tumor mice models. The vaccine has thus reached a further important pre-clinical milestone. These are very important headline results as the therapeutic vaccine is being developed towards first in human clinical investigations in 2023.

The additional topline preclinical results reported today by ExpreS2ion are based on data from a new therapeutic study in HER2-transgenic mice transplanted subcutaneously with HER2-positive tumors. Two weeks after the inoculation of tumor cells, the first vaccine administration was given. HER2-transgenic mice are tolerant towards HER2 as anticipated in humans, which makes it more difficult to raise an immune response and prevent HER2-positive tumors from growing. ES2B-C001 formulated in an adjuvant effectively inhibited tumor development, whereas the control group progressively expanded with tumor development.

Furthermore, a preventive tumor study in HER2-transgenic mice showed that only 2 vaccinations with 2 weeks interval prevented tumor development with 95% efficiency as compared to a control group, where all mice spontaneously developed tumors as HER2-transgenic mice do over time.

In January 2022, ExpreS2ion will meet with DKMA (the Danish Medicines Agency) to receive regulatory authority pre-CTA (clinical trial application) advice on the CTA submission plan.

CEO Bent Frandsen comments:        

“These new and excellent topline results from the ExpreS2ion-sponsored on-going preclinical trial confirm that the ES2B-C001 breast cancer vaccine breaks HER2 tolerance and targets HER2 positive tumors, which is the ultimate goal for treatments in the breast cancer field. We remain on track to continue development towards a first in human trial in 2023.”

Results from the remaining on-going animal proof of concept studies are expected later in the first half of 2022. The vaccine project continues to be on path, with the start of the clinical program planned for 2022 with GMP manufacturing of ES2B-C001. This will be followed by, pending feedback from the regulatory authorities, the start of a clinical Phase I safety and immune response study in 2023.

About ES2B-C001 and breast cancer

Breast cancer is a widespread oncology indication affecting more than 1.3 million people worldwide annually, resulting in more than 450,000 deaths (Tao, 2015: www.ncbi.nlm.nih.gov/pubmed/25543329). The most common treatment today is based on monoclonal antibodies, where the dominating therapy Herceptin (trastuzumab) generates annual global sales of USD 7 billion. The target product profile of the HER2-cVLP breast cancer vaccine candidate is tailored to be highly competitive both in terms of cost and efficacy, thus aiming at a significant market share.

Certified Adviser

Svensk Kapitalmarknadsgranskning AB

Telefon: +46 11 32 30 732

E-post: ca@skmg.se

This press release constitutes inside information that ExpreS2ion Biotech Holding AB (publ) is obliged to make public pursuant to the EU Market Abuse Regulation 596/2014. The information was sent for publication, through the agency of the contact persons set out above, at the time stated by the Company’s news distributor, Cision, at the publication of this press release.

For further information about ExpreS2ion Biotech Holding AB, please contact:

Bent U. Frandsen, CEO
Telephone: +45 4256 6869

Keith Alexander, CFO
Telephone: +45 5131 8147

About ExpreS2ion

ExpreS2ion Biotechnologies ApS is a fully owned Danish subsidiary of ExpreS2ion Biotech Holding AB with company register number 559033-3729. ExpreS2ion has developed a unique technology platform, ExpreS2, for fast and efficient non-clinical development and production of complex proteins for new vaccines and diagnostics. ExpreS2 is regulatorily validated for clinical supply. The platform includes functionally modified glycosylation variants for enhanced immunogenicity and pharmacokinetics. Since 2010, the Company has produced more than 300 proteins and 40 virus-like particles (VLPs) in collaboration with leading research institutions and companies. Since 2017, ExpreS2ion develops novel capsid VLP based vaccines through its 34%-owned joint venture AdaptVac ApS. For additional information, please visit www.expres2ionbio.com and www.adaptvac.com.