Cartesian Therapeutics reports Q3 2026 financial results

Item 2.02 Results of Operations and Financial Condition.

On November 5, 2026, Cartesian Therapeutics, Inc. (the "Company") announced its financial results for the quarter ended September 30, 2026.¹ The full text of the press release issued in connection with the announcement is furnished as Exhibit 99.1 to this Current Report on Form 8-K.

The information in Item 2.02 of this Form 8-K, including Exhibit 99.1 attached hereto, 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 a filing.

Item 9.01 Financial Statements and Exhibits.

(d) Exhibits

Exhibit No. Exhibit Description

99.1 Press release of Cartesian Therapeutics, Inc. issued on November 5 , 2026.²

104 Cover Page Interactive Data File (embedded within the Inline XBRL document)

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.

CARTESIAN THERAPEUTICS, INC.

Date: November 5, 2026 By: /s/ Carsten Brunn, Ph.D.

Carsten Brunn, Ph.D.

President, Chief Executive Officer and Chairman of the Board

Cartesian Therapeutics Reports Third Quarter 2026 Financial Results and Provides Business Update

In vivo CAR-T program, in partnership with WestGene BioPharma, continues to advance

Approximately $124.7 million cash, cash equivalents and restricted cash as of September 30, 2026, expected to support planned operations into 2028

Frederick, Md., November 5, 2026 (GLOBE NEWSWIRE) – Cartesian Therapeutics, Inc. (NASDAQ: RNAC) ("we", the "Company" or "Cartesian"), a late clinical-stage biotechnology company pioneering cell therapy for autoimmune diseases, today reported financial results for the third quarter ended September 30, 2026, and outlined recent business updates.

"With Phase 3 AURORA data expected in the first quarter of 2027, our focus this quarter remains on execution, both in the clinic and in preparing the organization for a commercial launch," said Carsten Brunn, Ph.D., President and Chief Executive Officer of Cartesian. "Ahead of our anticipated BLA submission in mid-2027, we have expanded our medical affairs and commercial teams to drive launch readiness. With larger teams on the ground now, we are excited by the opportunity to expand awareness of Descartes-08's differentiation, particularly on the back of the retreatment data we presented in September which continued to demonstrate deep and durable responses with a consistent safety profile, all with outpatient administration and no preconditioning chemotherapy. We believe this profile has the potential to meaningfully change how MG is treated. Beyond MG, we look forward to data from our TRITON and HELIOS trials expected in 2027 as we work to bring Descartes-08 to more patients with autoimmune diseases."

Pipeline Progress and Anticipated Milestones

• Phase 3 AURORA Trial of Descartes-08 in Participants with MG Advances Towards Expected Data Readout in 1Q27, with BLA Planned for Mid-2027. The randomized, double-blind, placebo-controlled Phase 3 AURORA trial is designed to assess Descartes-08, Cartesian's autologous anti-B cell maturation antigen (BCMA) chimeric antigen receptor T-cell therapy (CAR-T) versus placebo (1:1 randomization) administered as six once-weekly outpatient infusions without preconditioning chemotherapy in approximately 100 patients with acetylcholine receptor autoantibody positive (AChR Ab+) MG. The primary endpoint will assess the proportion of Descartes-08 participants with an improvement in MG Activities of Daily Living (MG-ADL) score of three points or more at Month 4 compared to placebo.

• Announced Retreatment Data for Descartes-08 Highlights Deep and Durable Responses in Patients with MG . In September 2026, Cartesian presented additional retreatment data at the Myasthenia Gravis Foundation of America Scientific Session of the 2026 American Association of Neuromuscular and Electrodiagnostic Medicine Annual Meeting. The analysis included five patients with MG who completed a full course of Descartes-08 in the Phase 2 portion of the trial and whose symptoms returned after 12 months of follow-up. Patients were retreated a median of 16.6 months following completion of the initial course. At Month 12 following retreatment, patients achieved a mean MG-ADL reduction of 6.6 (±4.2) points from baseline. All five retreated patients experienced a clinically meaningful reduction across MG Composite (MGC) (≥3-point reduction) and MG-ADL scores (≥2-point reduction), and four of five patients maintained clinically meaningful MG-ADL reduction through Month 12. Consistent safety data observed to date supports potential retreatment of Descartes-08 following recurrence of MG symptoms, as clinical benefit was observed with no new safety signals.

• Phase 2 TRITON Trial in Myositis Remains on Track with Data from Subset of Patients Expected in 1H27 to Inform Path Forward to Pivotal Trial. The randomized, double-blind, placebo-controlled Phase 2 TRITON trial in myositis is designed to assess Descartes-08 versus placebo (1:1 randomization) administered as six weekly outpatient infusions without preconditioning chemotherapy in patients with moderate to severe multi-refractory dermatomyositis and antisynthetase syndrome. The primary endpoint is to assess the safety and efficacy of Descartes-08 compared to placebo added to standard of care in participants with myositis. The Company plans to evaluate a subset of patients from the trial to determine the potential path to a pivotal trial in myositis.

• Phase 1/2 HELIOS Pediatric Trial of Descartes-08 in Autoimmune Diseases, Including JDM, Continues to Progress with Data Expected in 1H27. Enrollment remains ongoing in the Phase 1/2 HELIOS pediatric trial of Descartes-08 in children and young adults with autoimmune diseases, including JDM. JDM is a rare ped