Cullinan Oncology : Therapeutics Corporate Update

Cullinan Therapeutics

Autoimmune Disease Strategy

April 16, 2024

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Important Notice and Disclaimers

This presentation contains forward-looking statements within the meaning of The Private Securities Litigation Reform Act of 1995. 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.

Forward-looking statements in this presentation include, but are not limited to, statements about: the commercial success, cost of development, and timing of the approval of our clinical-stage product candidates; the initiation, timing, progress, results, and cost of our research and development programs and our current and future preclinical studies and clinical trials, including statements regarding the timing of initiation and completion of studies or clinical trials and related preparatory work, and the period during which the results of the trials will become available; our ability to submit, and obtain clearance of, any investigational new drug applications on our expected timelines, or at all; 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 therapies or developing product candidates with targets or indications similar to our product candidates' targets or indications; our reliance on third parties to conduct our clinical trials and to manufacture drug substance and drug product for use in our clinical trials; the size and growth potential of the markets for any of our current and future product candidates, 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 and future product candidates, if approved, including our ability to successfully build a specialty sales force and commercial infrastructure to market our current and future product candidates; our ability to identify research priorities and apply a risk-mitigated strategy to efficiently discover and develop current and future 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, pricing, and reimbursement; our estimates of our expenses, ongoing losses, capital requirements, the sufficiency of our current resources, and our needs for or ability to obtain additional financing; the milestone payments that we may receive from Taiho Pharmaceutical Co., Ltd.; potential investments in our pipeline and the potential for such product candidates; the potential benefits of strategic collaboration agreements, our ability to enter into additional strategic collaborations or arrangements, and our ability to attract collaborators with development, regulatory, and commercialization expertise; and developments and projections relating to our competitors or our industry. 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.

Any forward-looking statements in this presentation are based on management's current expectations and beliefs of future events and are subject to 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 timing and results of regulatory submissions, including the investigational new drug application that we intend to file for CLN-978; success of our clinical trials and preclinical studies; risks related to our ability to protect and maintain our intellectual property position; risks related to manufacturing, supply, and distribution of our product candidates; the risk that any one or more of our product candidates, including those that are co-developed, will not be successfully developed and commercialized; the risk that the results of preclinical studies or clinical studies will not be predictive of future results in connection with future studies; success of any collaboration, partnership, license or similar agreements; and other important risks and uncertainties discussed in our filings with the Securities and Exchange Commission, including under the caption "Risk Factors" in our most recent Annual Report on Form 10-K, Quarterly Report on Form 10-Q and other filings that we make with the SEC from time to time. These risks 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, except to the extent required by law. These forward-looking statements should not be relied upon as representing our views as of any date subsequent to the date of this presentation. Moreover, except as required by law, neither Cullinan nor any other person assumes responsibility for the accuracy and completeness of the forward-looking statements included in this presentation. Any forward-looking statement included in this presentation speaks only as of the date on which it was made.

Certain information contained in this presentation relates to or is based on studies, publications, surveys and other data obtained from third-party sources and our own internal estimates and research. While we believe these third-party sources to be reliable as of the date of this presentation, we have not independently verified, and make 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.

© CULLINAN THERAPEUTICS, INC. ALL RIGHTS RESERVED.

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CULLINAN THERAPEUTICS

On Today's Call

Nadim Ahmed

Chief Executive Officer

Jeff Jones, MD, MPH, MBA

Chief Medical Officer

Patrick Baeuerle, PhD

Chief Scientific Advisor

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Announcing Cullinan Therapeutics

• New Company name, Cullinan Therapeutics, reflects expansion of portfolio into autoimmune diseases.
• CLN-978to be developed exclusively in autoimmune diseases, with system lupus erythematosus (SLE) as a first indication.
• New observations from the B-NHL study show rapid, deep and sustained B cell depletion and clinical activity.
• CLN-978has the potential to be a first-in-class,off-the-shelf,disease-modifying treatment with a favorable safety profile in autoimmune disease.
• Recently announced equity finance transaction adds an additional $280M to our balance sheet and extends our cash runway into 2028.

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CLN-978 Opportunity in Autoimmune Diseases

CLN-978

CD19 x CD3 T Cell Engager

CLN-978 program update

-HSA	-CD19	-CD3
(VHH)	(scFv)	(scFv)

High affinity, enabling

lysis of target cells

with low CD19 target

expression

Albumin binding for	CD3 binder for T cell
extended serum half-life	redirected B cell lysis

Development of CD19xCD3 T cell engager in autoimmune diseases

• IND submission planned for SLE in 3Q 2024
• Planning for other autoimmune disease indications
• Enrollment in B-NHL study has been discontinued

Initial proof of concept from B-NHL clinical trial

• Clinical response achieved at first dose level
• Observed rapid, deep and sustained B cell depletion
• Favorable safety with only Grade 1 CRS; No ICANS

Strong potential for differentiation

• Potent modality due to broad T cell engagement
• Potential advantages over CAR T cell therapy
• Subcutaneous administration
• CD19 target has potential advantages over other targets (CD20, BCMA)

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HSA = human serum albumin binding domain, SLE = systemic lupus erythematosus,

CRS = cytokine release syndrome, ICANS = immune effector cell-associated neurotoxicity syndrome

Cullinan Oncology Pipeline Remains on Track

Program	IND-	Phase 1	Phase 2	Phase 3
Modality/MOA	Enabling

Status

Geographic

Rights

CLN-619			Initial combo data and
Pan-cancer	monotherapy update in	or its subsidiary
Anti-MICA/B antibody			2Q24; Disease specific
			expansion data in 1H25	owns worldwide rights
CLN-978	Systemic lupus erythematosus	IND submission
CD19xCD3 T-cell engager			expected in 3Q24	owns worldwide rights
Zipalertinib	NSCLC with exon 20 insertion mutations 2+ line	Pivotal Phase 2b 2L+
		study enrolled by YE24;	holds US co-development/-
(CLN-081/TAS6417)
NSCLC with exon 20 insertion mutations frontline	Phase 3 1L study
EGFRex20ins inhibitor	commercialization rights with
		actively enrolling
CLN-049	R/R AML, MDS	Clinical update from
FLT3xCD3 T-cell engager	ongoing Phase 1 study in
		or its subsidiary
			2H24
			owns worldwide rights
CLN-418	Multiple solid tumors	Clinical update from
B7H4x41BB bispecific immune	ongoing Phase 1 study in
activator			2H24	owns U.S. rights
CLN-617	Pan-cancer	Phase 1 study
Collagen-bindingIL-12 and IL-2
		ongoing
fusion protein			or its subsidiary
Early Programs	Multiple discovery stage programs		owns worldwide rights

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CLN-978: Clinical Observations

and Development Plans in Autoimmune Diseases

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CD19 CAR-T cell therapy generated immune system reset and durable, treatment-free remissions in autoimmune patients

Immune system reset: selected SLE PD data		Observations

Treatment free remissions in 3 autoimmune disease settings

		SLE patients (n=8)				IIM patients (n=3)			SSc patients (n=4)
SLEDAI-2K		ACR-EULAR Total Improvement Score			EUSTAR-AI Score

• Mueller et al. (2024) treated 15 autoimmune patients (SLE, IIM, & SSc)1 with autologous CD19 CAR T
• SLE and IIM patients had complete resolution of disease symptoms; SSc patients reduced severity of skin and lung disease
• All patients successfully stopped immunosuppressive medication without having relapses or worsening disease
• Supported by deep B cell depletion, followed by immune reset and sustained diminution of autoantibodies
• Sustained drug-free remission are highly unlikely to be induced by lymphodepletion alone (e.g., some pts w/ prior chemotherapy)

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Muller, F. et al. NEJM 2024. 1) SLE = Systemic Lupus Erythematosus, IIM = idiopathic inflammatory myositis, SSc = systemic sclerosis

CD19 CAR T was generally well tolerated across autoimmune indications studied; however infectious complications were frequent

Class Specific Adverse Events	Grade 1	Grade 2+

ICANS	1/15	0/15
CRS*	10/15	1/15
*6/15 patient received tocilizumab

• Safety profile generally favorable versus observed safety of CD19 CAR T for ALL or B-NHL
• Infectious complications were common during the 12 months after CD19 CAR T
• • 14/15 patients experienced urinary or respiratory tract infections, including 1 case of pneumonia requiring hospitalization
  • 4/15 experience 2 or more infection episodes
  • Two patients experienced herpes zoster reactivation

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Muller, F. et al. NEJM 2024. CRS = cytokine release syndrome. ICANS = immune effector cell-associated neurotoxicity syndrome ALL = acute lymphoblastic leukemia

CAR T cell therapy: Promising outcomes but multiple challenges may limit broad uptake in autoimmune diseases

Cell therapy limitations

• Available cellular therapies all require lymphodepleting chemotherapy, which has been associated with increased risk for infection, infertility, and secondary malignancies
• FDA has mandated boxed warnings across approved products highlighting the risk for secondary malignancies related to the CAR T cell therapy itself
• Complex manufacturing processes can introduce treatment delays for patients
• Reimbursement challenges continue to limit provider uptake for existing indications
• Treatment limited to specialized centers certified to provide CAR T cell therapies
• Prohibitive logistical and economic challenges will likely prevent retreatment upon relapse

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