8-K

UNITED STATESSECURITIES AND EXCHANGE COMMISSIONWASHINGTON, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934

Date of Report (Date of earliest event reported): August 07, 2025

CULLINAN THERAPEUTICS, INC.

(Exact name of Registrant as Specified in Its Charter)

Delaware	001-39856	81-3879991
(State or Other Jurisdiction<br>of Incorporation)	(Commission File Number)	(IRS Employer<br>Identification No.)
One Main Street<br><br>Suite 1350
Cambridge, Massachusetts		02142
(Address of Principal Executive Offices)		(Zip Code)
Registrant’s Telephone Number, Including Area Code: 617 410-4650
---

(Former Name or Former Address, if Changed Since Last Report)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

☐Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

☐Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

☐Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

☐Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Securities registered pursuant to Section 12(b) of the Act:

Title of each class	Trading<br>Symbol(s)	Name of each exchange on which registered
Common Stock, $0.0001 par value per share	CGEM	The Nasdaq Global Select Market

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§ 230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§ 240.12b-2 of this chapter).

Emerging growth company ☐

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

Item 2.02 Results of Operations and Financial Condition.

On August 7, 2025, Cullinan Therapeutics, Inc. (the "Company") announced its financial results for the quarter ended June 30, 2025. A copy of the press release is being furnished as Exhibit 99.1 to this Current Report on Form 8-K.

The information in this Item 2.02 and Exhibit 99.1 attached hereto is intended to be furnished and shall not be deemed "filed" for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the "Exchange Act") or otherwise subject to the liabilities of that section, nor shall it be deemed incorporated by reference in any filing under the Securities Act of 1933, as amended, or the Exchange Act, except as expressly set forth by specific reference in such filing.

Item 5.02 Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers.

On August 4, 2025, Anne-Marie Martin, Ph.D. notified the Board of Directors (the “Board”) of the Company of her intention to resign as a director of the Company effective as of August 7, 2025. As part of her resignation, Dr. Martin also resigned from the Nominating and Corporate Governance Committee of the Board (the “Nominating Committee”). Dr. Martin’s decision to resign was not the result of any disagreement with the Company on any matter relating to our operations, policies or practices.

Additionally, on August 4, 2025, David P. Ryan, M.D. notified the Board of his intention to resign as a director of the Company, effective as of August 7, 2025. As part of his resignation, Dr. Ryan also resigned from the Compensation Committee of the Board (the “Compensation Committee”). Dr. Ryan’s decision to resign was not the result of any disagreement with the Company on any matter relating to our operations, policies or practices.

Effective August 7, 2025, the Board appointed Mittie Doyle, M.D., FACR as a Class I director and as a member of the Nominating Committee and Andrew Allen, M.D., Ph.D. as a Class II director and as a member of the Compensation Committee.

Dr. Doyle, age 60, has served as the Chief Medical Officer of Avalo Therapeutics, Inc., a public biotechnology company, since July 2024. From September 2021 to July 2024, Dr. Doyle served as Chief Medical Officer at Aro Biotherapeutics, a private biotechnology company. Prior to that, she served as Vice President, Global Therapeutic Area Head, Immunology at CSL Behring, a global biotech company, from October 2017 to September 2021. Prior to her time at CSL Behring, Dr. Doyle held senior level roles as Vice President, Global Development Lead at Shire Pharmaceuticals from August 2016 to October 2017, Vice President, Clinical Research at Flexion Therapeutics from April 2015 to July 2016. Dr. Doyle currently serves on the board of directors of a private company and previously served on the board of directors of DICE Therapeutics (“DICE”), a public company, from March 2022 to August 2023, when DICE was acquired by Eli Lilly and Company. Dr. Doyle received a B.A. from Princeton University and her M.D. from Yale Medical School. She completed her postdoctoral training at Harvard Medical School including residency in Internal Medicine at Massachusetts General Hospital and a clinical/research fellowship in Rheumatology and Immunology at Brigham and Women’s Hospital. We believe Dr. Doyle is qualified to serve on our board of directors due to her extensive experience in leadership and immunology clinical development.

Dr. Allen, age 59, co-founded Gritstone bio, Inc. (“Gritstone”) and served as its President and Chief Executive Officer from August 2015 to December 2024. Prior to Gritstone, Dr. Allen co-founded Clovis Oncology, Inc., a public pharmaceutical development company, and served as its Executive Vice President of Clinical and Preclinical Development and Chief Medical Officer from March 2009 to July 2015. Prior to that role, from 2006 to 2008 he was Chief Medical Officer and Executive Vice President at Pharmion Corporation, a biotechnology company that was acquired by Celgene Corporation. Previously, Dr. Allen served in clinical development leadership roles at Chiron Corporation, a biotechnology company that was acquired by Novartis International AG, and Abbott Laboratories, a public medical devices and healthcare company, and worked at McKinsey & Company, where he advised life science companies on strategic issues. He currently serves on the board of directors of Adaptimmune Therapeutics plc, a public biotechnology company, as well as on the boards of multiple private companies. Dr. Allen previously served on the boards of directors of Sierra Oncology, Inc., a public biopharmaceutical company, from October 2017 until its acquisition by GSK in July 2022 and Epizyme, Inc., a public biopharmaceutical company, from June 2014 until November 2021. Dr. Allen qualified in medicine at Oxford University and received a Ph.D. in immunology from the Imperial College of Science, Technology, and Medicine in London. We believe Dr. Allen is qualified to serve on our board of directors due to his extensive experience in leadership and oncology clinical development.

Pursuant to the Company’s director compensation program, upon their appointment as directors, each of Dr. Doyle and Dr. Allen was granted an option on August 7, 2025 with a grant date fair value of $359,000. These options will vest as to one-third of the shares underlying such award on each of the first, second and third anniversaries of the date of grant of the award, subject to each of their continued service as a director. Also, under the Company’s director compensation program, on the dates of the Company’s annual meetings of stockholders, each non-employee director that is serving on the Company’s Board who did not previously receive an initial grant in the same year will receive an option to purchase shares of common stock of the Company with a grant date fair value of $215,000. Each of these options will vest on the twelve-month anniversary of the date of grant of the award (or, if earlier, the date of the next annual meeting of stockholders following the date of grant of the award), subject to the non-employee director’s continued service as a director. All options issued to non-employee directors under the Company’s director compensation program will become exercisable in full upon a change in control of the Company. Each of Dr. Doyle and Dr. Allen will also receive the standard cash retainers for their membership on the Board and the Committees they serve on, as set out in the Company's non-employee director compensation policy, a copy of which was filed as Exhibit 10.2 to the Company's Quarterly Report on Form 10-Q filed with the SEC on May 8, 2025.

Also in connection with each of Dr. Doyle and Dr. Allen’s elections to the Board, they will each enter into the Company’s standard form of indemnification agreement for directors, a copy of which was filed as Exhibit 10.4 to the Company’s Registration Statement on Form S-1 (File No. 333-251512) filed with the SEC on December 18, 2020. Pursuant to the terms of this agreement, the Company may be required, among other things, to indemnify the directors for some expenses, including attorneys’ fees, judgments, fines and settlement amounts incurred by her or him in any action or proceeding arising out of her or his service as a director.

There are no arrangements or understandings between Dr. Doyle and any other person pursuant to which she was appointed as a director of the Company. Dr. Doyle was not involved in any transactions with the Company in an amount exceeding $120,000 since the beginning of the Company’s last fiscal year and there are no such currently proposed transactions.

Similarly, there are no arrangements or understandings between Dr. Allen and any other person pursuant to which he was appointed as a director of the Company. Dr. Allen was not involved in any transactions with the Company in an amount exceeding $120,000 since the beginning of the Company’s last fiscal year and there are no such currently proposed transactions.

Item 9.01 Financial Statements and Exhibits.

(d) Exhibits

Exhibit No.	Description
99.1	Press release issued by Cullinan Therapeutics, Inc. on August 7, 2025, furnished herewith
104	Cover page from this Current Report on Form 8-K, formatted in Inline XBRL

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

			CULLINAN THERAPEUTICS, INC.
Date:	August 7, 2025	By:	/s/ Mary Kay Fenton
			Mary Kay Fenton<br>Chief Financial Officer

EX-99.1

Exhibit 99.1

Cullinan Therapeutics Provides Corporate Update and Reports Second Quarter 2025 Financial Results

CLN-978 program now actively enrolling across Phase 1 studies in systemic lupus erythematosus (SLE), rheumatoid arthritis (RA) and Sjögren’s disease

BCMA-directed bispecific T cell engager velinotamig in-licensed from Genrix Bio

Zipalertinib REZILIENT1 pivotal results shared in oral presentation at ASCO 2025 and in Journal of Clinical Oncology; multiple new data sets across a range of disease settings to be shared at IASLC 2025 WCLC and ESMO Congress 2025

Company appoints Mittie Doyle, M.D., and Andrew Allen, M.D., Ph.D., to its Board of Directors

CAMBRIDGE, Mass. August 7, 2025 (GLOBE NEWSWIRE) -- Cullinan Therapeutics, Inc. (Nasdaq: CGEM; “Cullinan”), a biopharmaceutical company focused on developing modality-agnostic targeted therapies, today provided an update on recent and anticipated business highlights and announced its financial results for the second quarter ended June 30, 2025.

“I am proud of the team’s strong execution throughout the first half of the year as we continue to advance the CLN-978 program across three active studies in SLE, RA, and Sjögren’s disease. With the addition of velinotamig, we further solidified our leadership position in the development of T cell engagers for autoimmune diseases. With these two programs, our portfolio covers the entire breadth of the B cell compartment. Recent data presented at the European Alliance of Associations for Rheumatology (EULAR) meeting reinforced the potential of T cell engagers as disease-modifying therapies across a wide spectrum of autoimmune diseases,” said Nadim Ahmed, Chief Executive Officer of Cullinan Therapeutics.

“We also continue making important progress across our oncology portfolio, recently sharing results from the pivotal Phase 2b portion of the REZILIENT1 study of zipalertinib at the 2025 ASCO Annual Meeting, and we look forward to sharing multiple new data sets at upcoming medical conferences. Pending discussions with the U.S. FDA, our partner Taiho plans to submit an NDA in relapsed EGFR ex20ins NSCLC later this year and expects to complete enrollment of the frontline study REZILIENT3 in the first half of 2026. We also plan to share clinical data for CLN-049, our FLT3xCD3 bispecific T cell engager, in patients with relapsed/refractory AML and MDS later this year. With $510.9 million in cash and investments and runway into 2028, we have the resources to generate multiple value-driving catalysts near term and beyond across both our immunology and oncology programs. Lastly, I am pleased to welcome Drs. Mittie Doyle and Andrew Allen to our Board of Directors. They are proven leaders with deep strategic and development expertise in immunology and oncology, respectively, and I believe their contributions will be invaluable as we continue to advance our programs. I would also like to thank Drs. Anne-Marie Martin and David Ryan for their contributions to our progress and success over the last several years.”

Portfolio Highlights

Immunology

• CLN-978 (CD19xCD3 bispecific T cell engager): Systemic lupus erythematosus, rheumatoid arthritis, and Sjögren’s disease

• The global Phase 1 study in patients with moderate to severe SLE is enrolling in the United States, Europe, and Australia, and the Company plans to share initial safety data and B cell depletion data from Part A of the study in Q4 2025.

• The Phase 1 study in patients with active, difficult-to-treat rheumatoid arthritis is enrolling in Europe. This company-sponsored study is being led by sites at FAU Erlangen-Nuremberg in Germany and Università Cattolica del Sacro Cuore in Italy. The Company plans to share initial data from this study during the first half of 2026.

• The global Phase 1 study in patients with active, moderate to severe Sjögren’s disease is enrolling in the U.S. and is now also active in Europe following recent regulatory approval.

• Velinotamig (BCMAxCD3 bispecific T cell engager): Autoimmune diseases

• In June 2025, the Company entered into an agreement with Genrix Bio for an exclusive global (ex-Greater China) license to velinotamig. Under the agreement, Cullinan paid Genrix Bio an upfront license fee of $20 million. In the future, Genrix Bio will also be eligible to receive up to $292 million in development and regulatory milestones plus up to an additional $400 million in sales-based milestones, as well as tiered royalties on potential ex-Greater China net sales.

• Genrix Bio plans to initiate a Phase 1 study in patients with autoimmune diseases in China by the end of 2025. Cullinan intends to use the data generated to accelerate global clinical development of the program. Following the completion of the Genrix Bio Phase 1 study, Cullinan will conduct all further development of velinotamig in autoimmune diseases.

Oncology

• Zipalertinib (EGFR ex20ins inhibitor), collaboration with Taiho Oncology: EGFR ex20ins NSCLC

• In June 2025, results from the pivotal Phase 2b portion of REZILIENT1 in patients with EGFR ex20ins NSCLC who have received prior therapy were shared at the 2025 ASCO Annual Meeting and published simultaneously in the Journal of Clinical Oncology. Cullinan plans to share updated efficacy and safety data in patients previously treated with amivantamab during a mini oral abstract session at the IASLC 2025 WCLC.

• Pending discussions with the U.S. Food and Drug Administration, Taiho plans to submit an NDA in relapsed EGFR ex20ins NSCLC by the end of 2025. Taiho expects to complete enrollment of the pivotal study REZILIENT3 in 1L EGFR ex20ins NSCLC in the first half of 2026.

• Taiho plans to share initial data from the REZILIENT2 cohort exploring zipalertinib in patients with uncommon EGFR mutations during a mini oral abstract session at the IASLC 2025 WCLC. Taiho also plans to share initial data from the REZILIENT2 cohort exploring zipalertinib in patients with active brain metastases at the ESMO Congress 2025.

• CLN-049 (FLT3xCD3 bispecific T cell engager): Acute myeloid leukemia (AML) and myelodysplastic syndrome (MDS)

• Enrollment continues in the Phase 1 study in patients with relapsed/refractory AML or MDS and the company plans to share clinical data from this study in Q4 2025.

• Enrollment also continues in the Phase 1 study in patients with measurable minimal residual disease in AML.

• CLN-619 (Anti-MICA/MICB monoclonal antibody): NSCLC and multiple myeloma

• Enrollment continues in the Phase 1 expansion cohorts in patients with NSCLC and the Phase 1 study in patients with relapsed/refractory multiple myeloma.

• CLN-617 (IL-2 and IL-12 cytokine fusion protein): Solid tumors

• Enrollment continues in the Phase 1 study in patients with advanced solid tumors.

Corporate Updates

• Mittie Doyle, M.D., and Andrew Allen, M.D., Ph.D., were appointed to the Board of Directors, effective August 7, 2025. Both board directors bring significant leadership experience, with Dr. Doyle having extensive immunology clinical development expertise, and Dr. Allen with extensive oncology clinical development experience. Anne-Marie Martin, Ph.D., and David Ryan, M.D., will resign from Cullinan’s Board of Directors effective August 7, 2025.

Second Quarter 2025 Financial Results

• Cash Position: Cash, cash equivalents, short- and long-term investments, and interest receivable were $510.9 million as of June 30, 2025. Cullinan continues to expect its cash resources to provide runway into 2028 based on its current operating plan.
• R&D Expenses: Research and development expenses were $61.0 million for the second quarter of 2025, compared to $36.3 million for the same period in 2024.
• G&A Expenses: General and administrative expenses were $14.8 million for the second quarter of 2025, compared to $13.8 million for the same period in 2024.
• Net Loss: Net loss attributable to Cullinan was $70.1 million for the second quarter of 2025, compared to $42.0 million for the same period in 2024.

About Cullinan Therapeutics

Cullinan Therapeutics, Inc. (Nasdaq: CGEM) is a biopharmaceutical company dedicated to creating new standards of care for patients. Cullinan has strategically built a diversified portfolio of clinical-stage assets that inhibit key drivers of disease or harness the immune system to eliminate diseased cells in both autoimmune diseases and cancer. Cullinan’s portfolio encompasses a wide range of modalities, each with the potential to be best and/or first in class. Anchored in a deep understanding of oncology, immunology, and translational medicine, we create differentiated ideas, identify the most appropriate targets, and select the optimal modality to develop transformative therapeutics across a wide variety of autoimmune and cancer indications. We push conventional boundaries from candidate selection to differentiated therapeutic, applying rigorous go/no go criteria at each stage of development to fast-track only the most promising molecules to the clinic and, ultimately, commercialization. With deep scientific expertise, our teams exercise creativity and urgency to deliver on our promise to bring new therapeutic solutions to patients. Learn more about Cullinan at https://cullinantherapeutics.com/, and follow us on LinkedIn and X.

Forward-Looking Statements

This press release contains forward-looking statements within the meaning of The Private Securities Litigation Reform Act of 1995. These forward-looking statements include, but are not limited to, express or implied statements regarding the company’s beliefs and expectations regarding: our preclinical and clinical developments plans and timelines for our product candidates, the clinical and therapeutic potential of our product candidates, the strategy of our product candidates, our research and development activities, our plans regarding future data presentations, our cash runway, and other statements that are not historical facts. The words “believe,” “continue,” “could,” “estimate,” “expect,” “intends,” “may,” “plan,” “potential,” “project,” “pursue,” “will,” and similar expressions are intended to identify forward-looking statements, although not all forward-looking statements contain these identifying words.

Any forward-looking statements in this press release 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 future results, performance or achievements 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; the risk that any INDs, NDAs or other global regulatory submissions we may file with the United States Food and Drug Administration or other global regulatory agencies are not cleared on our expected timelines, or at all; the success of our clinical trials and preclinical studies; the risks related to our ability to protect and maintain our intellectual property position; the 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; the effect of changes in global economic conditions, including uncertainties related to international trade policies, tariffs and supply chain dynamics on our business and operations; and the 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, including under the caption “Risk Factors” in our most recent Annual Report on Form 10-K and subsequent filings with the SEC, could cause actual results to differ materially from those indicated by the forward-looking statements made in this press release. 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 press release. Moreover, except as required by law, neither the company nor any other person assumes responsibility for the accuracy and completeness of the forward-looking statements included in this press release. Any forward-looking statement included in this press release speaks only as of the date on which it was made.

Cullinan Therapeutics, Inc.

Selected Condensed Consolidated Balance Sheet Data

(unaudited)

(in thousands)

	June 30, 2025		December 31, 2024
Cash, cash equivalents, investments, and interest receivable	$	510,898	$	606,917
Total assets	$	520,329	$	621,824
Total current liabilities	$	28,058	$	30,647
Total liabilities	$	28,183	$	31,496
Total stockholders’ equity	$	492,146	$	590,328

Cullinan Therapeutics, Inc.

Consolidated Statements of Operations

(unaudited)

(in thousands, except per share amounts)

	Three Months Ended June 30,						Six Months Ended June 30,
	2025			2024			2025			2024
Operating expenses:
Research and development	$	61,030		$	36,259		$	102,489		$	66,905
General and administrative		14,768			13,768			28,305			26,111
Total operating expenses		75,798			50,027			130,794			93,016
Loss from operations		(75,798	)		(50,027	)		(130,794	)		(93,016	)
Other income (expense):
Interest income		5,924			8,071			12,504			13,764
Other income (expense), net		(181	)		(72	)		(266	)		(116	)
Net loss		(70,055	)		(42,028	)		(118,556	)		(79,368	)
Net loss attributable to noncontrolling interests		—			—			—			(192	)
Net loss attributable to Cullinan	$	(70,055	)	$	(42,028	)	$	(118,556	)	$	(79,176	)
Basic and diluted net loss per share attributable to Cullinan:
Common stock	$	(1.07	)	$	(0.68	)	$	(1.81	)	$	(1.43	)
Preferred stock	$	(10.70	)	$	(6.83	)	$	(18.12	)	$	(14.26	)
Weighted-average shares used in computing net loss per share attributable to Cullinan:
Common stock		59,015			55,052			58,960			49,031
Preferred stock		648			648			648			648

Contacts:

Investors

Nick Smith

+1 401.241.3516

nsmith@cullinantx.com

Media

Rose Weldon

+1 215.801.7644

rweldon@cullinantx.com