UNITED STATES SECURITIES

AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 6-K

REPORT OF FOREIGN PRIVATE ISSUER

PURSUANT TO RULE 13a-16 OR 15d-16

UNDER THE SECURITIES EXCHANGE ACT OF 1934

For the Month of May 2020

Commission File Number: 001-38281

ERYTECH Pharma S.A.

(Translation of registrant’s name into English)

60 Avenue Rockefeller

69008 Lyon France

(Address of principal executive office)

Indicate by check mark whether the registrant files or will file annual reports under cover of Form 20-F or Form 40-F:

☒ Form 20-F         ☐ Form 40-F

Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101(b)(1): ☐

Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101(b)(7): ☐

INFORMATION CONTAINED IN THIS REPORT ON FORM 6-K

Press Release

On May 26, 2020, Erytech Pharma S.A. (the “Company”) issued a press release announcing the date of its combined shareholders’ meeting, the availability of preparatory documents for the meeting and certain other related details. A copy of the press release is attached to this Report on Form 6-K as Exhibit 99.1.

EXHIBITS

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.

Exhibit 99.1

ERYTECH’S COMBINED SHAREHOLDERS’ MEETING

Meeting held in closed session on June 26, 2020

Live webcast of the Shareholders’ Meeting

Availability of the preparatory documents for the Shareholders’ Meeting

Lyon (France), May 26, 2020 – Erytech Pharma (Euronext Paris and Nasdaq: ERYP), a clinical-stage biopharmaceutical company developing innovative therapies by encapsulating therapeutic drug substances inside red blood cells, is announcing that its Combined Shareholders’ Meeting will be held in French in closed session at 2pm CEST on Friday, June 26, 2020, and also the associated details.

In compliance with recent French legislation¹ and per the recommendations of the French financial markets authority (Autorité des Marchés Financiers or AMF), Erytech confirms that its Annual Ordinary and Extraordinary Shareholders Meeting will take place at 2pm (Paris time) on June 26, 2020 in a closed session, without any shareholders being present in person. Please note that the AMF strongly encourages shareholders to vote, as such right is a fundamental prerogative of each shareholder, by means of distance voting, with all votes to be cast ahead of the Shareholders’ Meeting.

Voting procedures

For your vote to count:

These documents must reach us by June 23, 2020.

In the event that a proxy is given to a natural or legal person, the proxy holder shall send its voting instruction to Société Générale, by e-mail to the following address: assemblees.generales@sgss.socgen.com. The deadline for receipt is June 22, 2020.

Shareholders’ Meeting to be held in closed session without any shareholders being present in person

All the requisite arrangements for the Shareholders’ Meeting to proceed smoothly amid the current health situation have been made:

¹ Law of 23 March 2020 to respond to COVID-19 and decree dated 25 March 2020

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Availability of the documents for the Shareholders’ Meeting

The notice of meeting including the agenda and the draft resolutions, together with the principal details for attending and voting at the Combined Shareholders’ Meeting was published in the French Bulletin of Legal Announcements no. 61 on May 20, 2020.

Shareholders have access to the preparatory and information documents for the Shareholders’ Meeting as provided for by law and the regulations. They may also be viewed on the Company website at: https://investors.erytech.com/general-meeting

About ERYTECH and eryaspase: www.erytech.com

ERYTECH is a clinical-stage biopharmaceutical company developing innovative red blood cell-based therapeutics for severe forms of cancer and orphan diseases. Leveraging its proprietary ERYCAPS^® platform, which uses a novel technology to encapsulate drug substances inside red blood cells, ERYTECH is developing a pipeline of product candidates for patients with high unmet medical needs. ERYTECH’s primary focus is on the development of product candidates that target the altered metabolism of cancer cells by depriving them of amino acids necessary for their growth and survival.

The Company’s lead product candidate, eryaspase, which consists of L-asparaginase encapsulated inside donor-derived red blood cells, targets the cancer cell’s altered asparagine and glutamine metabolism. Eryaspase is in Phase 3 clinical development for the treatment of second-line pancreatic cancer and in Phase 2 for the treatment of first-line triple-negative breast cancer. An investigator-sponsored Phase 2 study in second-line acute lymphoblastic leukemia is ongoing in the Nordic countries of Europe.

ERYTECH produces its product candidates for treatment of patients in Europe at its GMP-approved manufacturing site in Lyon, France, and for patients in the United States at its GMP manufacturing site in Princeton, New Jersey, USA.

ERYTECH is listed on the Nasdaq Global Select Market in the United States (ticker: ERYP) and on the Euronext regulated market in Paris (ISIN code: FR0011471135, ticker: ERYP). ERYTECH is part of the CAC Healthcare, CAC Pharma & Bio, CAC Mid & Small, CAC All Tradable, EnterNext PEA-PME 150 and Next Biotech indexes.

CONTACTS

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