Cellectis S A : Corporate Presentation - September 2022

Commitment to a Cure

Corporate Presentation

September 2022

NASDAQ: CLLS

EURONEXT GROWTH: ALCLS.PA

Forward-Looking Statements

This presentation 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 "designed to", "anticipate," "expected," "on track," "plan," "scheduled," and "will," or the negative of these and similar expressions.

These forward-looking statements, which 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 about advancement, timing and progress of clinical trials (including with respect to patient enrollment and follow-up), the timing of our presentation of data and submission of regulatory filings, the adequacy of our supply of clinical vials, the operational capabilities at our manufacturing facilities, and the sufficiency of cash to fund operations.

These forward-looking statements are made in light of information currently available to us and are subject to numerous risks and uncertainties, including with respect to the numerous risks associated with biopharmaceutical product candidate development as well as the duration and severity of the COVID-19 pandemic and governmental and regulatory measures implemented in response to the evolving situation.

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 and the financial report (including the management report) for the year ended December 31, 2021 and subsequent filings Cellectis makes with the Securities Exchange Commission from time to time, 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.

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Cellectis at a Glance

Ongoing			Global GMP		Near-Term Clinical		$135M
4 Clinical Trials			Facilities		Catalyst
40+ patients dosed in		•	Operational since mid-2021		• UCART clinical data updates		Cash Runway into 2024*
	•	End-to-end manufacturing
Cellectis-sponsored trials			autonomy

Diversified Partnerships with Industry Leaders

~200+ patients dosed to date

• Revenues > $4B in milestones + royalties
• 6 trials sponsored by Cellectis' licensed partners

*Cash position, includes cash, cash equivalents and financial assets and restricted cash.

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UCARTs are "Off-The-Shelf"

Scalable

Manufacturing

Reduced cost

Scalable manufacturing: 1 batch = 100s doses

Robustness		Market Access

The goal is to provide	Immediately available
potency and consistency	to all eligible patients
to each patient

Control Production & Costs for Patients Safety and Profitability

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Experts in Gene-Editing Use TALEN®

High rates of gene editing for

knock outs and knock ins

		Efficient
In clinic since 2015	Mature	Safe	Protein / DNA interaction with
~200 patients dosed	32 base pairs recognition

WHY

TALEN®?

Euchromatin &	Genome	Precise	Targets desired site with a
heterochromatin	Outreach	maximum 7 bps range

Base Editors

TALE Base Editing

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