CYAD Celyad Oncology SA

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 January 2024

Commission File Number: 001-37452

CELYAD ONCOLOGY SA

(Translation of registrant’s name into English)

9 rue André Dumont

1435 Mont-Saint-Guibert, Belgium

(Address of principal executive offices)

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):  ☐

Celyad Oncology SA

On January 16, 2024, Celyad Oncology SA (the “Company”) issued a press release announcing its financial and operating results for the fourth quarter of 2023.

A copy of the Company’s press release is attached hereto as Exhibit 99.1 and is incorporated herein by reference.

The information contained in this Current Report on Form 6-K, including Exhibit 99.1, except for the quote of Michel Lussier contained in Exhibit 99.1, is hereby incorporated by reference into the Company’s Registration Statements on Forms F-3 (File No. 333-248464) and S-8 (File No. 333-220737).

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

Celyad Oncology provides fourth quarter 2023 business update and 2024 outlook

Three main pillars to unlock the potential of proprietary technology platforms and intellectual property:

Mont-Saint-Guibert, Belgium; January 16, 2024, 10:01 pm CET—Celyad Oncology (Euronext: CYAD) (the “Company”), today provides a fourth quarter 2023 business update and an outlook for 2024.

Michel Lussier, interim Chief Executive Officer of Celyad Oncology, commented: “2023 has been a very important year for Celyad Oncology, after the changes that occurred in 2022. Our research team has made a remarkable progress to broaden the range of cancer indications that could be targeted by chimeric antigen receptor (CAR) T-cells and to tackle the main limitations of current CAR T-cell therapies. We have shared new data at several scientific and business conferences along the year, and published in high impact peer-reviewed journals. We are eager to see the impact of our efforts to unleash the power of our IP estate and stay at the forefront of next-generation CAR T-cell development.”

2023 corporate accomplishments

2023 operational highlights

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		Press Release

Financial highlights

As of December 31, 2023, the Company had cash and cash equivalents of €3.0 million and short-term investments of €4.0 million. The Company projects that its existing cash, cash equivalents and short-term investments should be sufficient to fund operating expenses and capital expenditure requirements into the second quarter of 2025. Therefore, the Company continues to project that its existing cash and cash equivalents will be sufficient to fund its estimated operating and capital expenditures over at least the next 12 months from the date of this press release.

Outlook for 2024

Financial Calendar 2024

The financial calendar is communicated on an indicative basis and may be subject to change.

About Celyad Oncology

Celyad Oncology is a cutting-edge biotechnology company dedicated to pioneering the discovery and advancement of revolutionary technologies for chimeric antigen receptor (CAR) T-cells. Its primary objective is to unlock the potential of its proprietary technology platforms and intellectual property, enabling to be at the forefront of developing next-generation CAR T-cell therapies. By fully leveraging its innovative technology platforms, Celyad Oncology aims to maximize the transformative impact of its candidate CAR T-cell therapies and redefine the future of CAR T-cell treatments. Celyad Oncology is based in Mont-Saint-Guibert, Belgium. For more information, please visit www.celyad.com.

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		Press Release

Celyad Oncology Forward-Looking Statement

This release may contain forward-looking statements, within the meaning of applicable securities laws, including the Private Securities Litigation Reform Act of 1995, as amended, including, without limitation, statements regarding beliefs about and expectations for the Company’s updated strategic business model, including associated potential benefits, transactions and partnerships, statements regarding the potential value of the Company’s IP, and statements regarding the continuation of the Company’s existence, its cash and cash runway. The words “will,” “potential,” “continue,” “target,” “project,” “should” and similar expressions are intended to identify forward-looking statements, although not all forward-looking statements contain these identifying words. Any forward-looking statements in this release are based on management’s current expectations and beliefs and are subject to a number of known and unknown risks, uncertainties and important factors which might cause actual events, results, financial condition, performance or achievements of Celyad Oncology to differ materially from those expressed or implied by such forward-looking statements. Such risks and uncertainties include, without limitation, risks related to the material uncertainty about the Company’s ability to continue as a going concern; the Company’s ability to realize the expected benefits of its updated strategic business model; the Company’s ability to develop its IP assets and enter into partnerships with outside parties; the Company’s ability to enforce its patents and other IP rights; the possibility that the Company may infringe on the patents or IP rights of others and be required to defend against patent or other IP rights suits; the possibility that the Company may not successfully defend itself against claims of patent infringement or other IP rights suits, which could result in substantial claims for damages against the Company; the possibility that the Company may become involved in lawsuits to protect or enforce its patents, which could be expensive, time-consuming, and unsuccessful; the Company’s ability to protect its IP rights throughout the world; the potential for patents held by the Company to be found invalid or unenforceable; and other risks identified in Celyad Oncology’s U.S. Securities and Exchange Commission (SEC) filings and reports, including in the latest Annual Report on Form 20-F filed with the SEC and subsequent filings and reports by Celyad Oncology. These forward-looking statements speak only as of the date of publication of this document and Celyad Oncology’s actual results may differ materially from those expressed or implied by these forward-looking statements. Celyad Oncology expressly disclaims any obligation to update any such forward-looking statements in this document to reflect any change in its expectations with regard thereto or any change in events, conditions or circumstances on which any such statement is based, unless required by law or regulation.

Celyad Oncology Contacts:

Investor & Media Contact:

David Georges, VP Finance and Administration

investors@celyad.com

communications@celyad.com

Source: Celyad Oncology SA

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