Form 8-K
8-K — Cullinan Therapeutics, Inc.
Accession: 0001193125-26-411011
Filed: 2026-10-02
Period: 2026-10-01
CIK: 0001789972
SIC: 2836 (BIOLOGICAL PRODUCTS (NO DIAGNOSTIC SUBSTANCES))
Item: Regulation FD Disclosure
Item: Other Events
Item: Financial Statements and Exhibits
Documents
8-K — cgem-20261001.htm (Primary)
EX-99.1 (cgem-ex99_1.htm)
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8-K
8-K (Primary)
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UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, 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): October 01, 2026
CULLINAN THERAPEUTICS, INC.
(Exact name of Registrant as Specified in Its Charter)
Delaware
001-39856
81-3879991
(State or Other Jurisdiction
of Incorporation)
(Commission File Number)
(IRS Employer
Identification No.)
One Main Street
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
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 7.01 Regulation FD Disclosure.
On October 1, 2026, Cullinan Therapeutics, Inc. (the "Company") issued a press release announcing the initiation of a new drug application ("NDA") submission to the United States Food and Drug Administration (the "FDA") for zipalertinib in combination with platinum-based chemotherapy for the treatment of patients with previously untreated, locally advanced or metastatic non-small cell lung cancer ("NSCLC") harboring epidermal growth factor receptor ("EGFR") exon 20 insertion ("ex20ins") mutations under the FDA's Real-Time Oncology Review Program ("RTOR"). A copy of the press release is furnished as Exhibit 99.1 to this Current Report on Form 8-K and is incorporated herein by reference.
The information in this Current Report on Form 8-K furnished pursuant to Item 7.01, including Exhibit 99.1 attached hereto, shall not be deemed to be "filed" for the purposes of Section 18 of the Exchange Act, or otherwise subject to the liabilities of that section and will not be incorporated by reference into any filing by the Company under the Securities Act or the Exchange Act, unless specifically identified as being incorporated therein by reference.
Item 8.01 Other Events.
On October 1, 2026, the Company announced the initiation of a NDA submission to the FDA for zipalertinib in combination with platinum-based chemotherapy for the treatment of patients with previously untreated, locally advanced or metastatic NSCLC harboring EGFR ex20ins mutations under the FDA’s RTOR program. The RTOR program allows sponsors to submit clinical data in advance of the complete application to facilitate earlier review of efficacy and safety results. Completion of the Company's NDA submission is expected by year-end 2026.
The NDA submission is based on data from the Phase 3 REZILIENT3 trial, which met its primary endpoint, demonstrating a statistically significant and clinically meaningful improvement in median progression-free survival for zipalertinib plus chemotherapy compared to chemotherapy alone. These results were recently presented at the International Association for the Study of Lung Cancer’s 2026 World Conference on Lung Cancer during a Presidential Symposium.
Zipalertinib holds FDA Breakthrough Therapy designation for the treatment of patients with locally advanced or metastatic EGFR ex20ins NSCLC who have previously received platinum-based chemotherapy. An NDA seeking accelerated approval for zipalertinib monotherapy in this indication remains under FDA review, with a Prescription Drug User Fee Act target action date of February 27, 2027.
The Company is eligible to receive (i) a $30.0 million payment from Taiho upon U.S. regulatory approval of zipalertinib for the treatment of patients with locally advanced or metastatic EGFR ex20ins NSCLC who have previously received platinum-based systemic chemotherapy, and (ii) up to a $100.0 million payment from Taiho upon U.S. regulatory approval of zipalertinib for the first-line treatment for adult patients with locally advanced or metastatic EGFR ex20ins NSCLC.
Item 9.01 Financial Statements and Exhibits.
(d)
Exhibit No.
Description
99.1
Press release issued by Cullinan Therapeutics, Inc. on October 1, 2026, 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:
October 1, 2026
By:
/s/ Mary Kay Fenton
Mary Kay Fenton
Chief Financial Officer
EX-99.1
EX-99.1
Filename: cgem-ex99_1.htm · Sequence: 2
EX-99.1
Exhibit 99.1
New Drug Application Submission Initiated for Zipalertinib Plus Chemotherapy in First-Line EGFR Exon 20 Insertion Mutation NSCLC for Review Under FDA Real-Time Oncology Review Program
In the Phase 3 REZILIENT3 study, zipalertinib combination therapy demonstrated longest median progression-free survival observed to date in first-line EGFR exon20ins NSCLC
After agreement with the U.S. FDA, Real-Time Oncology Review program submission process initiated; completion of NDA submission expected by year-end 2026
CAMBRIDGE, Mass., October 1, 2026 (GLOBE NEWSWIRE) – Cullinan Therapeutics, Inc. (Nasdaq: CGEM), a clinical-stage biopharmaceutical company accelerating potential first- or best-in-class, disease-modifying T cell engagers in autoimmune diseases and cancer, today announced the initiation of a New Drug Application (NDA) submission to the U.S. Food and Drug Administration (FDA) for zipalertinib in combination with platinum-based chemotherapy for the treatment of patients with previously untreated, locally advanced or metastatic non-small cell lung cancer (NSCLC) harboring epidermal growth factor receptor (EGFR) exon 20 insertion (ex20ins) mutations under the FDA’s Real-Time Oncology Review (RTOR) program.
The RTOR program allows sponsors to submit clinical data in advance of the complete application to facilitate earlier review of efficacy and safety results. Completion of the NDA submission is expected by year-end 2026.
The NDA submission is based on data from the Phase 3 REZILIENT3 trial, which met its primary endpoint, demonstrating a statistically significant and clinically meaningful improvement in median progression-free survival for zipalertinib plus chemotherapy compared to chemotherapy alone. These results were recently presented at the International Association for the Study of Lung Cancer’s (IASLC) 2026 World Conference on Lung Cancer (WCLC) during a Presidential Symposium, where potentially practice-changing clinical data are highlighted.
Zipalertinib holds FDA Breakthrough Therapy designation for the treatment of patients with locally advanced or metastatic EGFR ex20ins NSCLC who have previously received platinum-based chemotherapy. An NDA seeking accelerated approval for zipalertinib monotherapy in this indication remains under FDA review, with a Prescription Drug User Fee Act (PDUFA) target action date of February 27, 2027.
Cullinan Therapeutics is eligible to receive $30 million and $100 million in milestone payments upon second-line and first-line U.S. regulatory approvals, respectively.
1
About Zipalertinib
Zipalertinib (development code: CLN-081/TAS6417) is an orally available small molecule designed to target activating mutations in EGFR. The molecule was selected because of its ability to inhibit EGFR variants with exon 20 insertion mutations. Zipalertinib is designed as a next generation, irreversible EGFR inhibitor for the treatment of a genetically defined subset of patients with non-small cell lung cancer. Zipalertinib is investigational and has not been approved by any health authority.
Zipalertinib is being developed by Taiho Oncology, Inc., its parent company, Taiho Pharmaceutical Co., Ltd., and in collaboration with Cullinan Therapeutics, Inc. in the U.S.
About EGFR Exon 20 Insertion Mutations
NSCLC is a common form of lung cancer and up to 4% of all cases globally have EGFR ex20ins.1 In the United States, approximately 16% of patients with NSCLC harbor EGFR mutations,1 with insertions at exon 20 accounting for up to 12% of these mutations.2
About Cullinan Therapeutics
Cullinan Therapeutics, Inc. (Nasdaq: CGEM) is a biopharmaceutical company developing potential first- or best-in-class, disease-modifying T cell engagers for autoimmune diseases and cancer. Cullinan pursues promising therapeutic targets while leveraging core expertise in T cell engagers, which are established in oncology and are now advancing into autoimmune diseases. With a clinical-stage pipeline built on a rigorous scientific approach and purposeful innovation, Cullinan is advancing its mission to deliver new standards of care for patients. Learn more about Cullinan at https://cullinantherapeutics.com/, and follow Cullinan 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 the clinical development of zipalertinib, the safety and efficacy profile of zipalertinib and its potential to address unmet medical need, the potential of zipalertinib to become a first-line treatment option, the anticipated timing of the completion of the NDA submission under the RTOR program 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.
2
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 clinical trial data and regulatory submissions; the risk that any NDAs, INDs or other global regulatory submissions we may file with the United States Food and Drug Administration or other global regulatory agencies are not accepted or 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 trials will not be predictive of future results in connection with future studies or clinical trials; 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.
Investors
Nick Smith
+1 401.241.3516
nsmith@cullinantx.com
3
Media
Rose Weldon
+1 215.801.7644
rweldon@cullinantx.com
References
1.
Burnett H, Emich H, Carroll C, et al. Epidemiological and clinical burden of EGFR exon 20 insertion in advanced non-small cell lung cancer: a systematic literature review. PLOS ONE. 2021;16(3): e0247620. Available at: https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0247620.
2.
Riess JW, Gandara DR, Frampton GM, et al. Diverse EGFR Exon 20 Insertions and Co-Occurring Molecular Alterations Identified by Comprehensive Genomic Profiling of NSCLC. Journal of Thoracic Oncology. 2018 Jul 5;13(10):1560–1568. Available at: https://www.jto.org/article/S1556-0864(18)30770-6/pdf.
4
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