Cellectis Receives $20 Million Convertible Note Under Collaboration Agreement with its Partner Cytovia Therapeutics

• Cellectis is developing custom TALEN® for Cytovia to develop gene-edited iPSC-derived Natural Killer cells
• Cytovia and Isleworth Healthcare Acquisition Corp. announce business combination agreement and combined company is expected to be listed on NASDAQ under the ticker symbol INKC
• $20 million note represents upfront collaboration consideration and would convert into common stock upon completion of the business combination

New York, NY – April 27, 2022 - Cellectis (the “Company”) (Euronext Growth: ALCLS - NASDAQ: CLLS), a clinical-stage biotechnology company using its pioneering gene-editing platform to develop life-saving cell and gene therapies, announces today that its partner Cytovia Therapeutics, LLC (“Cytovia”), a biopharmaceutical company empowering natural killer (“NK”) cells to fight cancer through stem cell engineering and multispecific antibodies, entered into a definitive business combination agreement with Isleworth Healthcare Acquisition Corp. (NASDAQ: ISLE) (“Isleworth”), a Special Purpose Acquisition Company (“SPAC”).

Concurrent with the business combination agreement, Cellectis received a $20 million convertible note in payment of the upfront collaboration consideration provided for pursuant to the research collaboration and non-exclusive license agreement entered between Cellectis and Cytovia in February 2021. The terms of the note provide for conversion into common stock of the combined company upon completion of the business combination, which is subject to the satisfaction or waiver of customary closing conditions. In connection with this convertible note, Cellectis received a warrant to purchase additional shares of the combined company representing up to 35% of the shares issued upon conversion of the note at a predetermined exercise price, with the number of shares issuable upon exercise and the exercise subject to certain adjustments.

« We are impressed by the progress Cytovia has accomplished in the past months. Cytovia shares Cellectis’ mission to provide life-saving off-the-shelf allogeneic cell therapies to patients, and we are excited to be providing them with best-in-class TALEN® gene editing for cell therapy applications. Congratulations to the Cytovia team for this transaction, which is an important milestone as they continue their journey to progress gene-edited NK therapeutics towards a cure for cancer! » said André Choulika, CEO of Cellectis.

Cellectis and Cytovia’s research and development collaboration:

In February 2021, Cellectis and Cytovia entered into a strategic research and development collaboration to develop TALEN® gene-edited iPSC NK and CAR-NK cells. In November 2021, Cellectis and Cytovia extended their collaboration to include new CAR target and development in China by Cytovia’s strategic partner, CytoLynx Therapeutics.

Financial terms of the collaboration include the $20 million convertible note as well as up to $805 million of development, regulatory, and sales milestones and single-digit royalty payments on the net sales of all partnered products commercialized by Cytovia.

Cellectis is developing custom TALEN®, which Cytovia uses to edit iPSCs. Cytovia is responsible for the differentiation and expansion of the gene-edited iPSC master cell bank into NK cells and is conducting the pre-clinical evaluation, clinical development, and commercialization of the mutually-agreed-upon selected therapeutic candidates. Cellectis has granted Cytovia a worldwide license under the patent rights over which Cellectis has control in this field, including in China, in order for Cytovia to modify NK cells to address multiple gene-targets for therapeutic use in several cancer indications.