Ad-Hoc Release detail page

Allschwil, Switzerland, June 1, 2021

Polyphor's balixafortide demonstrates consistent dual action anti-viral and anti-inflammatory activity in COVID-19 preclinical trials

- Balixafortide showed a clear anti-viral effect, different from remdesivir, in a 14-day laboratory (CPE) assay

- Balixafortide single agent treatment showed statistically significant reduction of viral load of SARS-CoV-2 in an animal study

- In this in-vivo study, balixafortide reduced COVID19-relevant inflammation markers correlated with severe disease progression and mortality in humans

- Polyphor has entered into several non-clinical academic collaborations with leading scientific institutions and is evaluating the feasibility of a Phase II clinical proof of concept study in patients with severe COVID-19 infections

- Conference call to discuss these results and the COVID-19 treatment landscape with 3 renowned scientific experts on June 10 at 8am ET/2pm CET

Polyphor AG (SIX: POLN), a research driven clinical stage, Swiss biopharmaceutical company committed to discovering and developing best-in-class molecules in oncology and antimicrobial resistance, today announced that its CXCR4 antagonist balixafortide demonstrated dual action anti-viral and anti-inflammatory activity in COVID-19 related research studies using clinically relevant concentrations.

Balixafortide is a potent, selective CXCR4 antagonist which is currently also in Phase III development in combination with eribulin in patients with metastatic HER-2 negative breast cancer. Results from this Phase III trial are expected for objective response rate (ORR) end of Q2 and for progression free survival (PFS) in Q4 2021.

In vitro experiments in collaboration with University of Basel confirm anti-viral activity of balixafortide against SARS-CoV-2

In a preclinical experiment using a CPE (cytopathic effect assay), balixafortide demonstrated strong and robust activity against SARS-CoV-2 (COVID-19) infection at clinically relevant concentrations with no adverse cytotoxic effects. Further in vitro experiments revealed a clear effect in a 14-day CPE assay which was different from remdesivir tested in parallel, suggesting a novel and unique mechanism of action and cell protection. The experiments were performed in a research collaboration with the University of Basel, Department of Biomedicine.

In vivo experiments confirm both anti-viral and anti-inflammatory activity in animal models

Based on positive in vitro findings, Polyphor has entered into academic collaborations with leading scientific institutions in the field of COVID-19 who are conducting non-clinical experiments to confirm in vivo efficacy and to understand mechanism of action. In an in vivo hamster animal model, balixafortide showed positive and statistically significant reduction of viral load of SARS COV-2. Balixafortide also reduced COVID19-relevant inflammation markers in the lung including ISG15 gene expression, a key player of respiratory failure in viral infections.

Based on these strong anti-viral and anti-inflammatory findings, in addition to the emerging evidence supporting CXCR4 as a potential target driving mortality in severe COVID-19 patients by escalating activation of bystander CXCR4+ T cells in the lungs (1), Polyphor is evaluating the feasibility of a Phase II clinical proof of concept study in patients with confirmed COVID-19 infections.

Key Opinion Leader Roundtable on COVID-19 conference call on Thursday, June 10^th at 8:00 AM ET / 2:00 PM CET

To register for the event, please click here or visit Polyphor's website at: https://www.polyphor.com/investor-relations/calendar/

The webinar will feature a presentation by Key Opinion Leaders Thomas Klimkait, Ph.D. (University of Basel), Andy Shorr, M.D. (Georgetown University) and Eliver Ghosn, Ph.D. (Emory University) who will discuss the current treatment landscape and unmet medical need in treating patients with COVID-19, and research that demonstrates the importance of the CXCR4 pathway in COVID-associated inflammation and mortality, respectively. Drs. Klimkait, Shorr, and Ghosn will be available to answer questions following the formal presentations.
Polyphor's management team will then discuss novel research findings of balixafortide relevant for COVID-19 infections.

(1) Neidleman et al. https://www.biorxiv.org/content/10.1101/2020.06.08.138826v1.full.pdf

For further information please contact:

For Investors:

For Media:

Bernhard Schmid
LifeSci Advisors
+41 44 447 12 21
bschmid@lifesciadvisors.com

About Polyphor
Polyphor is a research driven clinical-stage, Swiss biopharmaceutical company committed to discovering and developing best-in-class molecules in oncology and antimicrobial resistance leveraging the company's leading macrocyclic peptide technology platform. Polyphor is advancing balixafortide (POL6326) in a Phase III trial in combination with eribulin in patients with advanced breast cancer and exploring its potential in other cancer indications. In addition, it has discovered and is developing the Outer Membrane Protein Targeting Antibiotics (OMPTA). OMPTA are potentially the first new class of antibiotics in clinical development in the last 50 years against Gram-negative bacteria. The company's lead OMPTA program is an inhaled formulation of murepavadin for the treatment of Pseudomonas aeruginosa infections in patients with cystic fibrosis. Polyphor is based in Allschwil near Basel and is listed on the SIX Swiss Exchange (SIX: POLN). For more information, please visit www.polyphor.com.

Disclaimer
This press release contains forward-looking statements which are based on current assumptions and forecasts of the Polyphor management. Known and unknown risks, uncertainties, and other factors could lead to material differences between the forward-looking statements made here and the actual development, in particular Polyphor's results, financial situation, and performance. Readers are cautioned not to put undue reliance on forward-looking statements, which speak only of the date of this communication. Polyphor disclaims any intention or obligation to update and revise any forward-looking statements, whether as a result of new information, future events or otherwise.