Celyad : successfully completes safety follow-up of the first patient at the fourth dose level in the NKR-2 Phase I trial

• No safety issues or dose limiting toxicity reported in the first patient at the fourth dose level.
• Next patient, 11of the trial, has been infused.
• The trial is a dose escalation study evaluating safety and feasibility of NKR-2 T-cell therapy in patients with Acute Myeloid Leukemia or Multiple Myeloma.

Mont-Saint-Guibert, Belgium - Celyad (Euronext Brussels and Paris, and NASDAQ: CYAD), a leader in the discovery and development of cell therapies, today announced the successful completion of the 21-day safety follow-up of the first patient enrolled at the fourth dose level in its Phase I/IIa clinical trial evaluating the safety and feasibility of its NKR-2 T-cell therapy using T-cells engineered to express the NKG2D receptor in Acute Myeloid Leukemia and Multiple Myeloma patients. No safety issues or toxicities were reported.

Dr. Christian Homsy, CEO of Celyad: 'We are pleased that no adverse safety signal has been reported. The next patient of the cohort has already been infused. We continue to accumulate evidence in this human trial consistent with our pre-clinical data that no preconditioning or lymphodepletion is required to administer these unique natural killer receptor expressing T-cells successfully'.

Dr. Frédéric Lehmann, Head of Immuno-Oncology at Celyad: 'The absence of any safety or toxicity signal up to this point continues to support our belief that this unique engineered T-cell construct can be safely administered and potentially lead to a therapeutic effect providing hope to the thousands of patients who need better treatments for both AML and MM.'