Allschwil, Switzerland, July 16, 2021

Polyphor provides update on the future of the FORTRESS study of balixafortide and announces initial restructuring steps

- The company has decided to initiate the closing of the FORTRESS study

- The company plans to analyze progression free survival (PFS) for the study including all major sub-groups given data maturity for the overall population is reached

- The company will neither seek overall survival (OS) analysis as key secondary endpoint nor marketing approval related to this study

- The board of directors continues its strategic assessment regarding the future of the company and will provide an update not later than end of July

- A planned restructuring by up to 29 positions is expected to create operational efficiencies and reduce costs; consultation process with employees is initiated

Polyphor AG (SIX: POLN) announced today that due to the lack of meaningful clinical benefit based on objective response rate (ORR) and clinical response rate (CBR) in the third-line or later population and following a thorough analysis, the company has decided to initiate the closure of the FORTRESS study evaluating balixafortide (POL6326) in combination with eribulin for the treatment of patients with HER2-negative, locally recurrent or metastatic breast cancer. As data maturity is reached for the overall population, Polyphor plans to further analyze progression-free survival (PFS) data for the trial, including all major subgroups. However, the company will not seek an overall survival (OS) analysis as key secondary endpoint nor marketing approval in connection with this study. The company plans to present the data from the FORTRESS trial results analyses at a future medical meeting.

In order to reduce costs and increase operational efficiency, Polyphor plans to restructure by up to 29 positions. The consultation process with employees has already been initiated.

The board of directors continues the strategic assessment considering a full range of options regarding the future of the company and will provide an update not later than end of July.

For further information please contact:

For Investors:

For Media:

Dr. Stephan Feldhaus
Feldhaus & Partner
+41 79 865 92 56
feldhaus@feldhaus-partner.ch

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 has finished patient enrollment of a Phase III trial of balixafortide (POL6326) in combination with eribulin in patients with advanced breast cancer. 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.