MONT-SAINT-GUIBERT, Belgium–(BUSINESS WIRE)–Regulatory News:

Celyad Oncology SA (Brussels:CYAD) (Paris:CYAD) (NASDAQ:CYAD) (Euronext & Nasdaq: CYAD), a clinical-stage biotechnology company focused on the discovery and development of chimeric antigen receptor T cell (CAR T) therapies for cancer, today announced that Chief Scientific Officer, Dr. David Gilham, will participate in a panel discussion titled “Cell Therapies in the Next Decade” to be held on Wednesday, July 14th, at 08:55 a.m. EST at the William Blair Biotech Focus Conference 2021 taking place virtually from July 14-15, 2021. The management team will participate in one-on-one investor meetings throughout the conference as well.

A live audio webcast of the discussion can be accessed through the Events section of the Company’s website.

About Celyad Oncology SA

Celyad Oncology SA is a clinical-stage biotechnology company focused on the discovery and development of chimeric antigen receptor T cell (CAR T) therapies for cancer. The Company is developing a pipeline of allogeneic (off-the-shelf) and autologous (personalized) CAR T cell therapy candidates for the treatment of both hematological malignancies and solid tumors. Celyad Oncology was founded in 2007 and is based in Mont-Saint-Guibert, Belgium and New York, NY. The Company has received funding from the Walloon Region (Belgium) to support the advancement of its CAR T cell therapy programs. For more information, please visit www.celyad.com.

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. Forward-looking statements may include statements regarding: the safety and clinical activity of Celyad Oncology’s pipelines and financial condition, results of operation and business outlook. Forward-looking statements may involve known and unknown risks and uncertainties which might cause actual results, financial condition, performance or achievements of Celyad Oncology to differ materially from those expressed or implied by such forward-looking statements. Such risk and uncertainty includes the expected date of the Phase 1 trial initiation by year-end 2020, our development of additional shRNA-based allogenic candidates from our CYAD-200 series towards clinical trial, and the duration and severity of the COVID-19 pandemic and government measures implemented in response thereto. A further list and description of these risks, uncertainties and other risks can be found in Celyad Oncology’s U.S. Securities and Exchange Commission (SEC) filings and reports, including in its Annual Report on Form 20-F filed with the SEC on March 25, 2020 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.

Contacts

Investor and Media Contacts:

Sara Zelkovic

Communications & Investor Relations Director

Celyad Oncology

investors@celyad.com

Daniel Ferry

Managing Director

LifeSci Advisors, LLC

daniel@lifesciadvisors.com