ERYTECH Requested a Pre-BLA Meeting with the FDA to Discuss Path to Approval in ALL

ERYTECH Requested a Pre-BLA Meeting with the FDA
to Discuss Path to Approval in ALL

• ERYTECH invited by FDA to request a pre-BLA meeting
• First step in the marketing approval process with the FDA for eryaspase for the treatment of hypersensitive ALL patients based on the positive results of the NOPHO-sponsored Phase 2 clinical trial

---

Lyon (France) and Cambridge, MA (U.S.), April 20, 2021 – ERYTECH Pharma (Nasdaq & Euronext: ERYP), a clinical-stage biopharmaceutical company developing innovative therapies by encapsulating therapeutic drug substances inside red blood cells, today announced the initiation of the process of seeking marketing approval from the U.S. Food and Drug Administration (US FDA) for its lead product candidate eryaspase in patients with acute lymphoblastic leukemia (ALL) who developed hypersensitivity reactions to PEG-asparaginase based on the positive results of the NOPHO-sponsored Phase 2 clinical trial.

Maintaining adequate asparaginase treatment following hypersensitivity to PEG-asparaginase is an important goal when treating patients with ALL. A global shortage of supply Erwinia-derived asparaginase, which is the current alternative treatment option to PEG-asparaginase, highlights the need for alternative treatment options for these patients.

Results from the NOPHO-sponsored Phase 2 clinical trial demonstrated that eryaspase in combination with chemotherapy, administered every two weeks, provides a sustained asparaginase enzyme activity level, and is generally well tolerated with few hypersentivity reactions. The trial results were presented at the 62^nd ASH Annual Meeting held in December 2020. The investigators positioned eryaspase as a potential attractive treatment option for patients who developed hypersensitivities to PEG-asparaginase.

ERYTECH initiated a dialogue with the US FDA in 2020 to evaluate the potential of eryaspase to be approved for the treatment of hypersensitive ALL patients based on the NOPHO-sponsored Phase 2 clinical trial. The FDA confirmed the unmet medical need and, following the review of a comprehensive data package submitted by ERYTECH, invited the Company to request a pre-BLA meeting to discuss the potential for the NOPHO-sponsored Phase 2 clinical trial to support marketing approval in the United States.