Cullinan Therapeutics Receives FDA Fast Track Designation for CLN-049, a Novel FLT3xCD3 T Cell Engager, in Relapsed/Refractory Acute Myeloid Leukemia
Rhea-AI Summary
Cullinan Therapeutics (Nasdaq: CGEM) announced that the U.S. FDA granted Fast Track designation to CLN-049, a FLT3xCD3 T cell engager, for treatment of relapsed/refractory acute myeloid leukemia (R/R AML) on December 1, 2025. The company said Phase 1 data in heavily pre-treated patients showed promising efficacy and favorable safety, including complete responses. CLN-049 Phase 1 results will be presented in an oral presentation at the 67th ASH Annual Meeting on December 8, 2025. Cullinan stated the Fast Track designation is intended to accelerate development and facilitate collaboration with the FDA to advance CLN-049 for patients with limited treatment options.
Positive
- FDA granted Fast Track designation for CLN-049 on Dec 1, 2025
- Phase 1 reported complete responses in heavily pre-treated AML patients
- CLN-049 Phase 1 data to be presented orally at ASH on Dec 8, 2025
Negative
- CLN-049 remains in Phase 1, indicating early-stage clinical risk for investors
News Market Reaction
On the day this news was published, CGEM declined 5.45%, reflecting a notable negative market reaction. Argus tracked a trough of -2.5% from its starting point during tracking. Our momentum scanner triggered 11 alerts that day, indicating notable trading interest and price volatility. This price movement removed approximately $36M from the company's valuation, bringing the market cap to $631M at that time.
Data tracked by StockTitan Argus on the day of publication.
Key Figures
Market Reality Check
Peers on Argus
Peers show mixed moves: AUTL up 3.25%, LXRX up 0.76%, PRTC down 0.06%, INBX down 2.36%, VIGL flat. No clear sector-wide trend tied to this AML Fast Track news.
Historical Context
| Date | Event | Sentiment | Move | Catalyst |
|---|---|---|---|---|
| Dec 08 | CLN-049 ASH data | Positive | +17.5% | Updated Phase 1 CLN-049 AML data with notable CR/CRh and manageable safety. |
| Dec 01 | CLN-049 Fast Track | Positive | -5.5% | FDA Fast Track designation for CLN-049 in relapsed/refractory AML. |
| Nov 20 | Zipalertinib NDA start | Positive | +3.2% | Rolling NDA submission for zipalertinib in EGFR ex20ins NSCLC. |
| Nov 10 | Investor conferences | Positive | +3.5% | Participation in investor conferences and ASH analyst event announcement. |
| Nov 06 | Q3 results update | Positive | +0.6% | Q3 2025 update with CLN-049 efficacy signals and strong cash runway. |
Positive clinical and corporate milestones have usually led to gains, but a prior CLN-049 Fast Track headline saw a -5.45% divergence.
Over recent months, Cullinan reported strong CLN-049 AML data, FDA Fast Track for CLN-049 on Dec 1, 2025, and an oral CLN-049 ASH presentation on Dec 8, 2025. Zipalertinib advanced toward an NDA with positive Phase 1/2 data, while the company also highlighted conference participation and Q3 2025 financials with a cash position of $475.5M supporting runway into 2029. The current Fast Track announcement fits this sequence of trial-driven regulatory catalysts in oncology.
Market Pulse Summary
The stock moved -5.5% in the session following this news. A negative reaction despite Fast Track status would echo the prior CLN-049 Fast Track headline, which coincided with a -5.45% move. The company still reported compelling Phase 1 AML data and holds cash and investments of $475.5M with runway into 2029. Any sharp downside could reflect repositioning after recent gains, not necessarily a change in the regulatory or clinical trajectory outlined in recent filings and ASH updates.
Key Terms
fast track designation regulatory
t cell engager medical
flt3xcd3 medical
relapsed/refractory medical
acute myeloid leukemia medical
AI-generated analysis. Not financial advice.
Promising efficacy and favorable safety data from the Phase 1 study in heavily pre-treated patients show potential of CLN-049 to address a broad population of AML patients
CAMBRIDGE, Mass., Dec. 01, 2025 (GLOBE NEWSWIRE) -- Cullinan Therapeutics, Inc. (Nasdaq: CGEM), a clinical-stage biopharmaceutical company accelerating potential first- or best-in-class, high-impact therapies in autoimmune diseases and cancer, today announced that the U.S. Food and Drug Administration (FDA) has granted Fast Track designation to CLN-049 for the treatment of relapsed/refractory (R/R) acute myeloid leukemia (AML). Data from the Phase 1 clinical trial of CLN-049 will be presented at the upcoming 67th American Society of Hematology (ASH) Annual Meeting and Exposition in an oral presentation on December 8.
“Fast Track designation underscores both the urgent need for new options in relapsed and refractory acute myeloid leukemia and the promise of CLN-049,” said Jeffrey Jones, MD, MBA, Chief Medical Officer, Cullinan Therapeutics. “Initial results from our Phase 1 study have shown meaningful efficacy, including complete responses, reinforcing the broad potential of this FLT3-directed T cell engager in a population where effective treatment options are currently limited and fragmented. This regulatory milestone provides important momentum for development, and we look forward to collaborating closely with the FDA to rapidly advance CLN-049 for patients who desperately need more effective therapies.”
About Fast Track Designation
FDA’s Fast Track designation is designed to facilitate development and expedite the regulatory review of investigational therapies to treat serious conditions and that have the potential to fulfill an unmet medical need. The FDA created this process to help deliver important new therapies to patients earlier and it covers a broad range of serious illnesses. Designated clinical programs may also be eligible to apply for Accelerated Approval and Priority Review if relevant criteria are met.
About CLN-049
CLN-049 is a novel, investigational FLT3xCD3 bispecific T cell engager. CLN-049 is designed to target FLT3-expressing leukemia cells, offering a new immunotherapeutic approach for treating acute myeloid leukemia (AML) and myelodysplastic syndrome (MDS). CLN-049 binds to both mutated and non-mutated FLT3, allowing targeted action regardless of FLT3 mutational status, making the investigational treatment widely applicable to a broad population.
CLN-049 is being studied in a Phase 1, open-label, multicenter, first-in-human, multiple ascending dose study evaluating safety, tolerability, pharmacokinetics (PK), pharmacodynamics, and preliminary efficacy of intravenously (IV) administered CLN-049 in patients with relapsed/refractory AML or MDS (NCT05143996) and in a parallel Phase 1, open-label, dose escalation and dose expansion study for the treatment of patients with AML with measurable residual disease (MRD) (EUCT 2023-506572-27-00).
About Acute Myeloid Leukemia
Acute myeloid leukemia (AML) is a cancer of the blood and bone marrow and the most common form of acute leukemia in adults.1,2 It is characterized by the rapid growth of abnormal white blood cells that crowd out healthy cells, leading to infections, fatigue, and bleeding.3 Each year in the U.S., approximately 22,000 people are diagnosed with AML, and about half as many lives are lost to the disease.4 Globally, AML affects an estimated 144,000 people annually, with approximately 130,000 deaths.5
Despite recent advances, outcomes for patients with AML remain poor, particularly for those with relapsed or refractory disease, where five-year survival is
About Cullinan Therapeutics
Cullinan Therapeutics, Inc. (Nasdaq: CGEM; “Cullinan”) is a biopharmaceutical company developing potential first- or best-in-class, high-impact therapies 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: our clinical developments plans and timelines for CLN-049, the clinical and therapeutic potential of CLN-049, our plans regarding future data presentations, 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 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 approved 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 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.
Contacts:
Investors
Nick Smith
+1 401.241.3516
Nsmith@cullinantx.com
Media
Rose Weldon
+1 215.801.7644
Rweldon@cullinantx.com
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- American Association for Cancer Research. (2025). Acute Myeloid Leukemia. https://www.aacr.org/patients-caregivers/cancer/acute-myeloid-leukemia/
- National Cancer Institute. (2025). Acute Myeloid Leukemia Treatment (PDQ®)–Patient Version. https://www.cancer.gov/types/leukemia/patient/adult-aml-treatment-pdq
- Leptidis J., et al. (2014). Fatal cardiac tamponade as the first manifestation of acute myeloid leukemia. Am J Emerg Med 32(10). https://doi.org/10.1016/j.ajem.2014.02.045
- National Cancer Institute. (2025). Cancer Stat Facts: Leukemia — Acute Myeloid Leukemia (AML). https://seer.cancer.gov/statfacts/html/amyl.html
- Zhou, Y., et al. (2024). Global, regional, and national burden of acute myeloid leukemia, 1990–2021: A systematic analysis for the Global Burden of Disease Study 2021. Biomarker Research, 12(101). https://doi.org/10.1186/s40364-024-00649-y
- Moore, CG., et al. (2025). Treatment of Relapsed/Refractory AML—Novel Treatment Options Including Immunotherapy. Am J Hematol. (100)2. https://doi.org/10.1002/ajh.27584
- Shahzad, M., et al. (2024) What have we learned about TP53-mutated acute myeloid leukemia?. Blood Cancer J. 14(202). https://doi.org/10.1038/s41408-024-01186-5
- Kantarjian H., et al. (2021). Acute myeloid leukemia: current progress and future directions. Blood Cancer J. 11(2). https://doi.org/10.1038/s41408-021-00425-3
FAQ
What did Cullinan Therapeutics (CGEM) announce on December 1, 2025 about CLN-049?
When and where will Cullinan present CLN-049 Phase 1 data (CGEM)?
What clinical evidence did Cullinan cite to support Fast Track for CLN-049 (CGEM)?
How might FDA Fast Track designation affect CLN-049 development for CGEM shareholders?
Is CLN-049 approved for AML after the Fast Track designation (CGEM)?
