Cellectis S.A.

Cautionary Statement

This press release contains “forward-looking” statements within the meaning of applicable securities laws, including the Private Securities Litigation Reform Act of 1995. Forward-looking statements may be identified by words such as “expected,” “foresee,” “may,” “potential,” “promising,” “will” or the negative of these and/or similar expressions. These forward-looking statements are based on our management’s current expectations and assumptions and on information currently available to management, including information provided or otherwise publicly reported by our licensed partners. Forward-looking statements include statements about the potential of the pivotal Phase 2 BALLI-01 trial to be registrational phases, the advancement, timing and progress of clinical trials, the timing of our presentation of data, the potential safety and efficacy of our product candidates, the potential benefits of RMAT designation, the sufficiency of cash to fund operations, the potential benefit of our product candidates and technologies, and the outcomes of our collaboration agreements, including with AstraZeneca, Servier, and Allogene. These forward-looking statements are made in light of information currently available to us and are subject to significant risks and uncertainties, including with respect to the numerous risks associated with biopharmaceutical product candidate development. Actual results, performance or events may differ materially from those projected in any forward-looking statement. Many important factors may adversely affect such forward-looking statements and cause actual results to differ from those in any forward-looking statement, including, without limitation, inconclusive clinical trial results or clinical trials failing to achieve one or more endpoints; early data not being repeated in ongoing or future clinical trials; promising preclinical data not yielding positive clinical results; failures to secure required regulatory approvals; regulatory developments in the United States and European Union and its member countries, and other countries; disruptions from failures by third-parties on whom we rely in connection with our clinical trials; delays or negative determinations by regulatory authorities; changes or increases in oversight and regulation; increased competition, including within the hemato-oncology field, which may affect our assessment of the relative strategic priority of our various research and development programs; manufacturing delays or problems; inability to achieve enrollment targets; disagreements with our collaboration partners or failures of collaboration partners to pursue product candidates; legal challenges, including product liability claims or intellectual property disputes or disputes with respect to a licensing agreement; any failure to achieve potential benefits or our licensing agreements with licensees or to enter into future arrangements; the ability and willingness of licensees to actively pursue development activities under our collaboration agreements; commercialization factors, including regulatory approval and pricing determinations; disruptions to access to raw materials or starting material; delays or disruptions at our in-house manufacturing facilities; proliferation and continuous evolution of new technologies; capital resource constraints; the rate and degree of market acceptance of, and demand for, our product candidates; dislocations in the capital markets; and our ability to attract and retain key scientific and management personnel. Particular caution should be exercised when interpreting results from Phase 1 studies and results and interim data relating to a small number of patients – such results should not be viewed as predictive of future results. With respect to our cash runway, our operating plans, including product development plans, may change as a result of various factors, including factors currently unknown to us. Furthermore, many other important factors, including those described in our Annual Report on Form 20-F as amended and in our annual financial report (including the management report) for the year ended December 31, 2025 and subsequent filings Cellectis makes with the Securities Exchange Commission from time to time, which are available on the SEC’s website at www.sec.gov, as well as other known and unknown risks and uncertainties may adversely affect such forward-looking statements and cause our actual results, performance or achievements to be materially different from those expressed or implied by the forward-looking statements. Except as required by law, we assume no obligation to update these forward-looking statements publicly, or to update the reasons why actual results could differ materially from those anticipated in the forward-looking statements, even if new information becomes available in the future.

For further information on Cellectis, please contact:

Media contacts:

Pascalyne Wilson, Director, Communications, + 33 (0)7 76 99 14 33,

Patricia Sosa Navarro, Chief of Staff to the CEO, +33 (0)7 76 77 46 93,

media@cellectis.com