Company: RNAC
Filing Date: 2025-03-13
Form Type: 10-K
Source: 0001453687-25-000060
Chunk: 46

Company: Cartesian Therapeutics, Inc.
Filing Date: 2025-03-13
Form: 10-K
Item: Item 1
Chunk 46
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 three participants with detectable anti-acetylcholine receptor antibody levels before treatment had an average 42% reduction in antibody levels by Month 6. These reductions deepened to 68% by Month 9 and persisted at Month 12. In summary, we observed continued clinical improvement and autoantibody reductions after BCMA directed mRNA CAR-T treatment for MG that persisted through the one-year follow-up period.

Follow-on results of the Phase 2b portion of the trial were presented in December 2024. The trial reached its primary endpoint to assess the proportion of patients achieving a five-point or greater reduction in their MGC score at day 85. Patients received six weekly infusions at the dose established in Phase 1b (52.5 x106 cells/kg). The trial also involved a crossover component, in which any patient originally assigned to placebo was given the opportunity to receive Descartes-08 after completing trial treatment.

In the Phase 2b trial, we observed a deepening of responses after Month 3 in the primary efficacy data set. Two MG composite responders at Month 3 withdrew from the study before Month 4 for personal reasons (total number of participants at Month 4 and Month 6 was 12). Of the 12 participants as of the readout date, eight had reached Month 9 follow-up and five had reached Month 12 follow-up, thus completing the trial. Results of the study showed an average MG-ADL reduction of 5.5 points at Month 4 (chart below on the left) and an average MGC reduction of 7.1 for Descartes-08 treated patients (chart below on the right), both of which exceed the thresholds clinicians generally consider clinically meaningful, defined as a reduction in MG-ADL score of at least two points and a reduction in MGC score of at least three points. Additionally, at Month 6, one third of all participants were observed to achieve minimal symptom expression. This is consistent with what we observed in the Phase 2a trial, where deepest responses were observed to occur at Month 6 and Month 9.

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Additionally, 80% of all participants who reached Month 12, including both responders and non-responders at Month 3, were observed to maintain clinically meaningful responses as measured by both MG-ADL and MGC. We also observed that 57% of the participants with no prior exposure to biologic therapy, achieved minimal symptom expression at Month 6. Of the two participants