Tuesday, Cartesian Therapeutics Inc ( RNAC ) announced topline results from its Phase 2b trial of Descartes-08 in patients with generalized myasthenia gravis (MG).

Descartes-08, Cartesian’s lead product candidate, is an autologous mRNA-engineered chimeric antigen receptor T-cell therapy (mRNA CAR-T) directed against the B cell maturation antigen.

It is designed to be administered as an outpatient treatment without requiring lymphodepleting chemotherapy to achieve activity with conventional CAR-T cell therapies.

The trial achieved its primary endpoint with statistical significance in the pre-specified mITT efficacy population, with 71% (10/14) of patients treated with Descartes-08 observed to have 5-point or greater improvements in MG Composite (MGC) score at Month 3 compared to 25% (3/12) of patients treated with placebo (p=0.018). MGC score aims to assess the disease severity.

In addition, the trial also achieved its primary endpoint with statistical significance in the per-protocol population, with 69% (11/16) of patients treated with Descartes-08 observed to have 5-point or greater improvements in MGC score compared to 33% (5/15) of patients treated with placebo (p=0.048).

Descartes-08 responders experienced deep improvements across the MG severity scales. The improvements seen at Month 3 persisted or improved in patients evaluated at Month 4 (n=5) and Month 6 (n=3) follow-up visits.

Descartes-08 demonstrated a favorable safety profile and was tolerated well, and adverse events were transient and mostly mild.

There were no cytokine release syndrome or immune effector cell-associated neurotoxicity syndrome cases.

Cartesian also announced updated results from two patients enrolled in the Phase 2a open-label portion of the trial.

Both retreated patients experienced rapid improvement in clinical scores and maintained minimal symptom expression for up to one year after receiving a second treatment cycle.

The time course and magnitude of treatment response upon retreatment were similar to those seen when the patients were first treated.

Four of the seven patients from the Phase 2a portion of the trial maintained clinically meaningful responses for at least one year following initial dosing.

Cartesian Therapeutics ( RNAC ) has also dosed the first patient in its Phase 2 open-label clinical trial evaluating Descartes-08 in patients with systematic lupus erythematosus. The Phase 2 open-label trial will enroll up to 30 adult patients.

Concurrently, Cartesian Therapeutics ( RNAC ) has entered into a private investment in public equity financing of approximately $130 million.

The company is selling 3.56 million shares and 2.94 million Series B Non-Voting Convertible Preferred Stock at a purchase price of $20.00 per share.

Price Action: RNAC shares are down 17.6% at $20.00 during the premarket session at last check Tuesday.