Company: RNAC
Filing Date: 2025-11-13
Form Type: 8-K
Source: 0001453687-25-000123
Chunk: 1

Company: Cartesian Therapeutics, Inc.
Filing Date: 2025-11-13
Form: 8-K
Item: Item 8.01
Chunk 1
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Item 8.01 Other Events

On November 13, 2025, the Company announced initial data from its ongoing Phase 2 trial of Descartes-08 in participants with SLE. The Phase 2 open-label trial was designed to evaluate outpatient administration of Descartes-08 without preconditioning chemotherapy or integrating vectors for the treatment of participants with moderate or severe SLE refractory to immunosuppressant therapy. The primary outcome measure assesses safety and tolerability, with secondary outcome measures assessing preliminary efficacy.

• Initial data reported significant reduction in disease activity following initial Descartes-08 treatment with 100% of participants who reached Month 3 follow-up (n=3) achieving Lupus Low Disease Activity State (LLDAS) response, defined by specific criteria that indicate low disease activity, improved patient outcomes, and sustained symptom improvement. A fourth patient has not yet reached Month 3 as of November 13, 2025. These results further validate the clinical effect of Descartes-08 in the field of autoimmune disease and the Company will continue to analyze the data from SLE to determine the next steps for the program.

• Disease remission reported as DORIS response was seen in two out of three participants at Month 3. DORIS is defined as the Definition of Response in SLE indicating a clinical SLE Disease Activity Index (SLEDAI)-2K score of 0 and physician global assessment (PGA) of less than 0.5.

• Descartes-08 continues to be observed as well-tolerated, supporting outpatient administration without the need for lymphodepleting chemotherapy. Adverse events were transient and mostly mild, and notably, there were no cases of cytokine release syndrome (CRS), and no cases of immune effector cell-associated neurotoxicity syndrome (ICANS).

• Correlative biomarkers support application of Descartes-08 in multiple autoimmune diseases observed through a statistically significant (p<0.01) decrease in proinflammatory cytokines associated with SLE pathogenesis (IL7, IL10, CCL20, ST1A1). Additionally, significant decreases were observed in plasmacytoid dendritic cells (pDCs) three months after receiving Descartes-08 in both myasthenia gravis (MG) and SLE patients, supporting the expansion into myositis, an autoimmune indication with a known pDC correlation.

On November 13, 2025, the Company also announced