Cullinan Oncology : Corporate Presentation December 2022

Mining for

Tomorrow's Cures

Cullinan Oncology Overview

Q4 2022

Important notice and disclaimers

This Presentation contains forward-looking statements and information. All statements other than statements of historical facts contained in this Presentation, including statements regarding our strategy, future financial condition, future operations, projected costs, prospects, plans, objectives of management and expected market growth, are forward-looking statements. In some cases, you can identify forward-looking statements by terminology such as "may," "will," "should," "expect," "intend," "plan," "anticipate," "believe," "estimate," "target," "seek," "predict," "potential," "continue" or the negative of these terms or other comparable terminology. Although we believe that the expectations reflected in these forward-looking statements are reasonable, these statements relate to our strategy, future operations, future financial position, future revenue, projected costs, prospects, plans, objectives of management and expected market growth, and involve known and unknown risks, uncertainties and other factors that may cause our actual results, levels of activity, performance or achievements to be materially different from any future results, levels of activity, performance or achievements expressed or implied by these forward-looking statements. Forward-looking statements in this presentation include, but are not limited to, statements about: the success, cost and timing of our clinical development of our product candidates, including zipalertinib, CLN-619, and CLN-049; the initiation, timing, progress, results, and cost of our research and development programs and our current and future preclinical and clinical studies, including statements regarding the timing of initiation and completion of studies or trials and related preparatory work, the period during which the results of the trials will become available, and our research and development programs; our ability to initiate, recruit and enroll patients in and conduct our clinical trials at the pace that we project; our ability to obtain and maintain regulatory approval of our product candidates, and any related restrictions, limitations or warnings in the label of any of our product candidates, if approved; our ability to compete with companies currently marketing or engaged in the development of treatments that our product candidates are designed to target; our reliance on third parties to conduct our clinical trials and to manufacture drug substance for use in our clinical trials; the size and growth potential of the markets for oncology and immuno-oncologic diseases and any of our current product candidates or other product candidates we may identify and pursue, and our ability to serve those markets; our ability to identify and advance through clinical development any additional product candidates; the commercialization of our current product candidates and any other product candidates we may identify and pursue, if approved, including our ability to successfully build a specialty sales force and commercial infrastructure to market our current product candidates and any other product candidates we may identify and pursue; our ability to identify research priorities and apply a risk-mitigated strategy to efficiently discover and develop product candidates; our ability to retain and recruit key personnel; our ability to obtain and maintain adequate intellectual property rights; our expectations regarding government and third- party payor coverage and reimbursement; our estimates of our expenses, ongoing losses, capital requirements and our needs for or ability to obtain additional financing; express or implied statements regarding our beliefs and expectations regarding the milestone payments we may receive from Taiho; the anticipated development and commercialization of zipalertinib; the development of our commercial infrastructure; potential investments in our pipeline and the potential for such product candidates; and our cash runway; the potential benefits of strategic collaboration agreements, our ability to enter into strategic collaborations or arrangements, and our ability to attract collaborators with development, regulatory and commercialization expertise; our financial performance; developments and projections relating to our competitors or our industry; the effect of the COVID-19 pandemic, including mitigation efforts and economic effects, on any of the foregoing or other aspects of our business operations, including but not limited to our preclinical studies and future clinical trials. We caution the Recipient not to place considerable reliance on the forward-looking statements contained in this presentation. The forward-looking statements in this presentation speak only as of the date of this document, and we undertake no obligation to update or revise any of these statements. Our business is subject to substantial risks and uncertainties, including those referenced above.

These forward-looking statements involve known and unknown risks and uncertainties that may cause our actual results, performance or achievements to be materially different from any expressed or implied by the forward-looking statements. These risks include, but are not limited to, the following: uncertainty regarding the results of regulatory submissions, including our ability to agree with the FDA on an acceptable trial design for CLN-049; success of our clinical trials and preclinical studies; risks related to manufacturing, supply and distribution of our therapeutic candidates; and success of any collaboration, partnership, license or similar agreements. These and other important risks and uncertainties discussed in our filings with the Securities and Exchange Commission, or SEC, including under the caption "Risk Factors" in our Prospectus dated January 7, 2021 filed with the SEC on January 11, 2021 and subsequent filings with the SEC, could cause actual results to differ materially from those indicated by the forward-looking statements made in this presentation. While we may elect to update such forward-looking statements at some point in the future, we disclaim any obligation to do so, even if subsequent events cause our views to change. These forward-looking statements should not be relied upon as representing our views as of any date subsequent to the date of this presentation.

Certain information contained in this Presentation relates to or is based on studies, publications, surveys and other data obtained from third-party sources and the Company's own internal estimates and research. While the Company believes these third-party sources to be reliable as of the date of this Presentation, it has not independently verified, and makes no representation as to the adequacy, fairness, accuracy or completeness of, any information obtained from third-party sources. In addition, all of the market data included in this Presentation involves a number of assumptions and limitations, and there can be no guarantee as to the accuracy or reliability of such assumptions. Finally, while we believe our own internal research is reliable, such research has not been verified by any independent source.

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C U L L I N A N O N C O L O G Y

Our Mission

• Discovering and developing medicines for high-impact oncology targets
• Pursuing modality-agnostic targeted oncology: We identify the best approach for each target
• Rigorously and rapidly advancing only highly differentiated molecules

Creating new standards of care for patients with cancer

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C U L L I N A N O N C O L O G Y

Our Approach

We seek to achieve our mission through our rigorous and differentiated approach to drug development

Run early "thriller or killer"	Seek clear evidence of	Innovate without
experiments	monotherapy activity	borders
Rapidly advance only first-in-class	Avoid uncertainty of early-stage	Remain open to finding the best solutions in-
and/or best-in-class molecules	clinical combination studies	house or through licensing

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C U L L I N A N O N C O L O G Y

Our Vision

OUR To become a fully integrated, commercial

oncology company creating

VISION new standards of care for patients with cancer

Develop robust capabilities as fully-integrated,end-to-end biotech

• Expand our deep domain expertise in oncology drug development
• Leverage our commercial expertise to develop capabilities to support marketing and sales of portfolio

Advance and expand our portfolio

• Progress candidates through regulatory approval
• Broaden and diversify our pipeline with new drug candidates

Allocate our capital with discipline

• Maintain a strong cash runway to support our pipeline
• Invest in new programs that align with our Mission and Approach

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