UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 FORM 10-Q þ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended June 30, 2025 OR ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from _______ to _______ Commission File Number: 001-37798 Cartesian Therapeutics, Inc. (Exact name of registrant as specified in its charter) Delaware 26-1622110 (State or oth ...

Cartesian Therapeutics Reports Second Quarter 2025 Financial Results and Provides Business Update Exhibit 99.1 Initiated Phase 3 AURORA trial of Descartes-08 in myasthenia gravis Preliminary data from Phase 2 trial of Descartes-08 in systemic lupus erythematosus expected in 2H25 Initiation of Phase 2 pediatric basket trial of Descartes-08 in select autoimmune indications expected in 2H25 Approximately $162.1 million cash, cash equivalents and restricted cash as of June 30, 2025, expected to support planned ...

Pipeline and Clinical Trials - Cartesian Therapeutics is pioneering mRNA cell therapies for autoimmunity, with multiple anticipated near-term catalysts[5] - Phase 3 AURORA study of Descartes-08 for Myasthenia Gravis (MG) is expected to commence in 1H25[8] - An open-label Phase 2 trial of Descartes-08 in Systemic Lupus Erythematosus (SLE) is ongoing, with data readout expected in 2H25[8] - A Phase 2 pediatric basket trial, including juvenile SLE, juvenile MG, and other conditions, is expected to initiate in 2H25[8, 12] - Dosing is underway in a first-in-human Phase 1 dose escalation trial for Descartes-15, a next-generation mRNA CAR-T candidate[8] Descartes-08 Efficacy and Safety - In a Phase 2b trial, participants treated with Descartes-08 maintained deep and durable responses over 12 months[16] - At Month 4, participants in the primary efficacy dataset experienced an average MG-ADL reduction of 5.5 points[23] - 33% of participants achieved minimum symptom expression at Month 6[23] - 80% of participants reaching Month 12 maintained a clinically meaningful response[23] - In participants with no prior exposure to biologics, the average MG-ADL reduction was 6.6 points at Month 4[26] - 57% of participants with no prior exposure to biologics achieved minimum symptom expression at Month 6[26] - 100% of participants with no prior exposure to biologics reaching Month 12 maintained a clinically meaningful response[26] - The safety profile of Descartes-08 supports outpatient administration, with no new types of adverse events reported[16, 28] Financial Position - Cartesian Therapeutics has a strong balance sheet with approximately $220.9 million as of September 30, 2024[9] - This is expected to support planned operations, including completion of the planned Phase 3 trial of Descartes-08 for MG, into mid-2027[9]

Financial Performance - Total revenue for Q1 2025 was $1.1 million, a decrease of 81.1% compared to $5.84 million in Q1 2024[19] - Net loss for Q1 2025 was $17.71 million, significantly improved from a net loss of $56.82 million in Q1 2024[19] - The company reported a basic and diluted net loss per share of $0.68 for Q1 2025, compared to $10.50 for Q1 2024[19] - The net loss for the three months ended March 31, 2025, was $17.71 million, compared to a net loss of $56.82 million for the same period in 2024[27] - For the three months ended March 31, 2025, total revenue was $1.1 million, a decrease of 81.1% compared to $5.84 million for the same period in 2024[150] - The net loss for the three months ended March 31, 2025, was $17.7 million, compared to a net loss of $56.8 million for the same period in 2024, representing a 68.9% improvement[150] Research and Development - Research and development expenses increased to $14.67 million in Q1 2025, up 50.1% from $9.74 million in Q1 2024[19] - Research and development expenses totaled $14.7 million for the three months ended March 31, 2025, an increase of 51.1% from $9.7 million in the same period in 2024[157] - The lead product candidate, Descartes-08, showed that 83% of participants maintained clinically meaningful improvements in myasthenia gravis severity scales at six months[153] Cash and Liquidity - Cash and cash equivalents decreased to $180.43 million as of March 31, 2025, down 15.1% from $212.61 million at the end of 2024[16] - The company reported cash, cash equivalents, and restricted cash of $182.10 million at the end of the period, down from $214.28 million at the beginning of the period[27] - As of March 31, 2025, the Company reported cash, cash equivalents, and restricted cash totaling $182.1 million, with $1.7 million being restricted cash related to lease commitments[43] - The company expects to fund its operating expenses and capital expenditures into mid-2027 based on current cash resources[160] - The company expects to continue incurring losses and will require additional capital to fund operations, potentially through equity offerings and collaborations[9] Assets and Liabilities - Total assets decreased to $409.13 million as of March 31, 2025, down 5.9% from $435.02 million at the end of 2024[16] - Total liabilities were $430.92 million as of March 31, 2025, a slight decrease from $441.83 million at the end of 2024[16] - The accumulated deficit increased to $709.78 million as of March 31, 2025, compared to $692.07 million at the end of 2024[16] - The Company had an accumulated deficit of $709.8 million as of March 31, 2025[156] Financing Activities - Cash used in operating activities for the three months ended March 31, 2025, was $23.11 million, an increase from $15.92 million in the prior year[27] - The company experienced a net cash used in financing activities of $8.03 million for the three months ended March 31, 2025, compared to a net cash provided of $43.03 million in the same period of 2024[27] - The company completed a private placement for the issuance of 149,330.115 shares of Series A Preferred Stock for approximately $60.25 million[32] - The Company completed a private placement resulting in gross proceeds of approximately $130.0 million from the sale of 3,563,247 shares of common stock and 2,937,903 shares of Series B Preferred Stock at $20.00 per share[98] Stock and Equity - The weighted-average common shares outstanding increased to 25,902,650 in Q1 2025 from 5,414,020 in Q1 2024[19] - The Company has authorized shares of common stock for future issuance totaling 12,374,230 as of March 31, 2025[104] - The company had 2,475,023 outstanding common stock options as of March 31, 2025, with a weighted-average exercise price of $13.96[114] - The company granted 256,790 restricted stock unit awards during the three months ended March 31, 2025, with a weighted-average fair value of $16.93 per share[115] Lease Obligations - The Company entered into a lease agreement for 19,199 square feet of manufacturing and office space at 7495 New Horizon Way, with an annual base rent of $0.9 million, subject to a 3% annual increase[78] - The total future minimum lease payments as of March 31, 2025, amount to $18.1 million, with total operating lease liabilities recorded at $14.1 million[95] - The company has lease obligations totaling approximately $9.0 million for laboratory and office space in Watertown, Massachusetts, through May 2028[203] Collaboration and Revenue - The company has not generated product revenue and relies primarily on collaboration agreements for revenue[42] - Collaboration and license revenue dropped to $0.4 million, down 93% from $5.8 million due to the termination of the Astellas Agreement[2] - The company recorded revenue of $5.8 million related to the Astellas Agreement during the three months ended March 31, 2024, but no revenue was recognized for the same agreement in 2025[119] Future Outlook - The Company is dependent on raising additional capital to fund its operations and product development, which may not be available on favorable terms[41] - The company expects that existing cash and equivalents will fund operations into mid-2027, but may need to seek additional funding sooner if actual results differ from estimates[201] - The Company must initiate a Phase 3 clinical trial by Q4 2024 and submit a BLA by Q4 2026 under the NCI Agreement[137]

[Business and Pipeline Update](index=1&type=section&id=Business%20and%20Pipeline%20Update) Cartesian Therapeutics updated its clinical pipeline, detailing progress for Descartes-08 in autoimmune diseases and Descartes-15 for multiple myeloma [Overview and Key Milestones](index=1&type=section&id=Overview%20and%20Key%20Milestones) Cartesian Therapeutics reported a strong start to 2025, highlighting positive long-term data for Descartes-08 in MG and outlining key upcoming clinical milestones - Initiation of the Phase 3 AURORA trial for Descartes-08 in myasthenia gravis (MG) is expected in **Q2 2025**[1](index=1&type=chunk)[3](index=3&type=chunk) - Preliminary data from the Phase 2 trial of Descartes-08 in systemic lupus erythematosus (SLE) are anticipated in the **second half of 2025**[1](index=1&type=chunk)[2](index=2&type=chunk)[9](index=9&type=chunk) - A Phase 2 pediatric basket trial for Descartes-08 in select autoimmune diseases is planned to start in the **second half of 2025**[1](index=1&type=chunk)[2](index=2&type=chunk)[9](index=9&type=chunk) - CEO Carsten Brunn highlighted that a single course of Descartes-08 therapy resulted in deep and sustained benefits at Month 12 for MG patients, particularly those without prior exposure to biologic therapies[2](index=2&type=chunk) [Descartes-08 Program](index=1&type=section&id=Descartes-08%20Program) Descartes-08 demonstrated sustained efficacy in MG Phase 2b, with a Phase 3 trial planned and expansion into other autoimmune indications - In the Phase 2b trial for MG, Descartes-08 treatment led to an average **4.8-point reduction in the MG-ADL score at Month 12**. Patients without prior biologic therapy exposure experienced a more significant **7.1-point reduction**[3](index=3&type=chunk) - The Phase 3 AURORA trial for MG is a randomized, placebo-controlled study set to begin in **Q2 2025**, enrolling about **100 patients**. The primary endpoint is a **≥3-point improvement in MG-ADL score at Month 4**[3](index=3&type=chunk)[4](index=4&type=chunk) - A Phase 2 pediatric basket trial is expected to initiate in **2H 2025**, targeting juvenile SLE, juvenile MG, juvenile dermatomyositis (JDM), and other vasculitis[9](index=9&type=chunk) - Descartes-08 is an autologous anti-BCMA CAR-T therapy that does not require preconditioning chemotherapy and avoids the risk of genomic integration. It has received Orphan Drug and Regenerative Medicine Advanced Therapy (RMAT) designations from the FDA for MG treatment[6](index=6&type=chunk) [Descartes-15 Program](index=2&type=section&id=Descartes-15%20Program) Descartes-15, a next-gen anti-BCMA CAR-T, is in Phase 1 for multiple myeloma, showing tenfold increased CAR expression, with future autoimmune plans - Dosing is ongoing in the first-in-human Phase 1 trial for multiple myeloma to assess safety and tolerability[9](index=9&type=chunk) - Descartes-15 is a next-generation therapy observed in preclinical studies to have an approximately **ten-fold increase in CAR expression** and selective killing compared to Descartes-08[7](index=7&type=chunk) - Similar to Descartes-08, it is designed for outpatient administration without preconditioning chemotherapy[7](index=7&type=chunk) - The company plans to assess Descartes-15 in autoimmune indications after the completion of the Phase 1 trial[9](index=9&type=chunk) [Financial Performance](index=1&type=section&id=First%20Quarter%202025%20Financial%20Results) Cartesian Therapeutics reported Q1 2025 financial results, showing a reduced net loss, strong cash, and shifts in operating expenses [Financial Highlights (Q1 2025)](index=1&type=section&id=Financial%20Highlights%20(Q1%202025)) Cartesian Therapeutics reported a Q1 2025 net loss of **$17.7 million**, a significant improvement, with **$182.1 million** cash expected to fund operations into mid-2027 - The company held **$182.1 million** in cash, cash equivalents, and restricted cash as of March 31, 2025, which is expected to support planned operations into **mid-2027**[1](index=1&type=chunk)[9](index=9&type=chunk) Q1 2025 Financial Summary | Metric | Q1 2025 | Q1 2024 | Change | | :--- | :--- | :--- | :--- | | Total Revenue | $1.1M | $5.8M | -81.2% | | R&D Expenses | $14.7M | $9.7M | +51.5% | | G&A Expenses | $8.3M | $9.5M | -12.6% | | Net Loss | $(17.7)M | $(56.8)M | Improved | | Net Loss Per Share | $(0.68) | $(10.50) | Improved | [Consolidated Balance Sheet](index=5&type=section&id=Consolidated%20Balance%20Sheets) As of March 31, 2025, total assets decreased to **$409.1 million**, primarily due to lower cash, with an increased stockholders' deficit Consolidated Balance Sheet Summary | Category | March 31, 2025 ($ thousands) | December 31, 2024 ($ thousands) | | :--- | :--- | :--- | | **Assets** | | | | Cash and cash equivalents | 180,434 | 212,610 | | Total Current Assets | 185,120 | 216,626 | | Total Assets | 409,130 | 435,023 | | **Liabilities & Stockholders' Deficit** | | | | Total Current Liabilities | 14,998 | 22,976 | | Total Liabilities | 430,919 | 441,825 | | Total Stockholders' Deficit | (21,789) | (6,802) | | **Total Liabilities & Stockholders' Deficit** | 409,130 | 435,023 | [Consolidated Statement of Operations](index=6&type=section&id=Consolidated%20Statements%20of%20Operations%20and%20Comprehensive%20Loss) Q1 2025 revenue decreased to **$1.1 million**, operating loss widened, but net loss significantly narrowed to **$17.7 million** due to fair value adjustments Consolidated Statement of Operations Summary | Metric ($ thousands) | Q1 2025 | Q1 2024 | | :--- | :--- | :--- | | Total Revenue | 1,100 | 5,840 | | Research and development | 14,674 | 9,738 | | General and administrative | 8,315 | 9,450 | | Operating loss | (21,889) | (13,348) | | Change in fair value of contingent value right liability | 346 | (39,300) | | Net loss | (17,710) | (56,824) | | Net loss per share (basic and diluted) | $(0.68) | $(10.50) |