 NEW YORK, March 29, 2021 GLOBE NEWSWIRE -- Cellectis S.A. NASDAQ: CLLS EURONEXT GROWTH: ALCLS the Company, a clinical-stage biotechnological company employing its core proprietary technologies to develop best-in-class products based on gene-edited allogeneic CAR T-cells in the field of immuno-oncology, today announced that it has filed a prospectus supplement with the Securities and Exchange Commission SEC relating to an At-The-Market ATM program, pursuant to which it may offer and sell to eligible investors a total gross amount of up to 125.0 million of American Depositary Shares ADS, each ADS representing one ordinary share of Cellectis, from time to time in sales deemed to be an at the market offering pursuant to the terms of a sales agreement with Jefferies LLC Jefferies, acting as sales agent. The timing of any sales will depend on a variety of factors. The ATM program is presently intended to be effective through the expiration of the existing registration statement, i.e. until June 2, 2023, unless terminated prior to such date in accordance with the sales agreement or the maximum amount of the program has been reached. 