Our Story Cellectis has 18 years of expertise in gene editing based on its flagship TALEN® technology and pioneering electroporation system PulseAgile. Cellectis is a clinical-stage biopharmaceutical company that harnesses the immune system to target and eradicate cancers. Unlike autologous CAR-T immunotherapies that require a custom immunotherapy product for each patient, Cellectis uses gene editing to create cost-effective, "off-the-shelf" (allogeneic) products (UCART) from healthy donors that can be immediately available for patients across all geographies. What’s more, for patients without enough T-cells for autologous CAR T therapy, Cellectis can create T-cells based on patients’ own T-cells. Cellectis has 18 years of expertise in gene editing based on its flagship TALEN® technology and pioneering electroporation system PulseAgile. This enables us to develop a new generation of immunotherapy product candidates with additional safety and efficacy attributes designed to prevent them from attacking healthy tissues, and equip them to resist mechanisms that inhibit immune system activity. And unlike autologous treatments that use the patient’s own T-cells – which get progressively weaker with each round of chemotherapy – Cellectis' allogeneic cells remain strong. Cellectis is listed on the Nasdaq Global Market (ticker: CLLS) and on the Alternext market of Euronext (ticker: ALCLS). TALEN® is a registered trademark owned by Cellectis. Editing Life Here are some of our milestones 1999 2005 2007 2008 2010 2011 2014 2015 2016 2017 2018 1999: Cellectis is founded In 2000, Institut Pasteur grants exclusive rights on 9 patent families, including several based on André Choulika’s research, genesis of the gene editing field. PREVIOUS NEXT Partners Our partners share the same objective to develop allogeneic cancer therapies that will benefit patients with unmet medical needs around the world. LEARN MORE LEGAL NOTICE CAREERS GLOSSARY MEDIA LIBRARY CONTACT Subsidiary: Calyxt Inc.

Research Cellectis is the pioneering gene editing company, deploying core proprietary technologies to develop off-the-shelf immunotherapies to target and eradicate cancer cells. Gene editing The principle of gene editing is very simple: in the same way that spell check identifies and corrects errors in a word or grammar errors in a sentence, gene editing can be used to precisely edit the genetic code within an individual's DNA. LEARN MORE Immuno-oncology Our product candidates, based on gene-edited T-cells that express Chimeric Antigen Receptors, or CARs, seek to harness the power of the immune system to target cancers. LEARN MORE Patents LEARN MORE Scientific publications LEARN MORE Product candidates Cellectis is designing next generation immunotherapies based on gene-edited allogeneic CAR T-cells. Allogeneic product candidates are a future-defining shift in simplicity, availability, and cost effectiveness. LEARN MORE LEGAL NOTICE CAREERS GLOSSARY MEDIA LIBRARY CONTACT Subsidiary: Calyxt Inc.