 MONT-SAINT-GUIBERT, Belgium, May 05, 2021 GLOBE NEWSWIRE -- Celyad Oncology SA 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 it has received a transparency notification from Tolefi SA, dated 3 May 2021. 