Cartesian’s Descartes-08 retreatment data showed sustained MG-ADL and MGC improvements at 12 months in generalized myasthenia gravis.
Written By: Creola Gonsalves, MS Biotech
Reviewed By: Pharmacally Editorial Team
Cartesian Therapeutics reported 12-month retreatment data for Descartes-08 (NCT04146051), an investigational autologous BCMA-directed CAR-T therapy, in five patients with generalized myasthenia gravis (gMG). Retreatment produced sustained improvements in MG-ADL and Myasthenia Gravis Composite scores, with no new safety signals, while Phase 3 AURORA topline results are expected in the first quarter of 2027.
Retreatment Produced Sustained Symptom Improvement
The data, presented at the 2026 American Association of Neuromuscular and Electrodiagnostic Medicine (AANEM) Annual Meeting and Myasthenia Gravis Foundation of America (MGFA) Scientific Session, evaluated five patients who experienced recurrence of MG symptoms at least 12 months after completing their initial Descartes-08 treatment course.
Patients had a mean disease duration of 13 years and extensive treatment histories. The retreatment course consisted of six once-weekly Descartes-08 infusions, matching the initial treatment regimen. Patients received retreatment at a median of 16.6 months after completing their initial course.
At Month 12 after retreatment, mean MG-ADL scores had decreased by 6.6 points from baseline, with a standard deviation of 4.2 points. Mean Myasthenia Gravis Composite (MGC) scores decreased by 15 points, with a standard deviation of 6.2 points.
All five patients achieved clinically meaningful reductions in both measures. Four maintained a clinically meaningful MG-ADL response through Month 12, defined in the study as a reduction of at least 2 points. All patients achieved at least a 3-point reduction in MGC.
Safety Profile Remained Consistent
The retreatment data did not identify new safety concerns. Descartes-08 was generally well tolerated through 12 months, with adverse events described as transient and mild.
No serious adverse events occurred during retreatment. The five patients experienced no cases of cytokine release syndrome (CRS), immune effector cell-associated neurotoxicity syndrome (ICANS), cytopenias, or hypogammaglobulinemia.
The findings are relevant because CAR-T therapies in oncology can require intensive lymphodepleting chemotherapy and carry risks such as CRS and ICANS. Descartes-08 is being evaluated using an outpatient administration approach without lymphodepleting chemotherapy.
BCMA-Directed CAR-T Approach in MG
Descartes-08 is an autologous CAR-T therapy that targets B-cell maturation antigen (BCMA), a marker expressed on antibody-producing plasma cells. By targeting BCMA-positive immune cells, the therapy is being investigated as a way to reduce pathogenic autoantibody production associated with autoimmune diseases such as MG.
MG is a chronic autoimmune neuromuscular disorder in which pathogenic antibodies disrupt signaling at the neuromuscular junction, causing fluctuating skeletal muscle weakness. Current treatment commonly relies on ongoing immunosuppression or repeated dosing of targeted therapies.
Unlike conventional DNA-based CAR-T products, Descartes-08 uses an RNA-based CAR construct and does not require lymphodepleting chemotherapy. Cartesian is evaluating whether a finite treatment course can provide sustained clinical benefit while allowing retreatment if symptoms recur.
Phase 3 AURORA Data Expected in 2027
Descartes-08 has received FDA Regenerative Medicine Advanced Therapy (RMAT) and Orphan Drug designations for MG. The FDA has also provided written agreement under the Special Protocol Assessment process that the overall Phase 3 AURORA trial design is acceptable to support a potential future biologics license application, subject to the trial outcome.
Cartesian expects topline AURORA results in the first quarter of 2027 and anticipates filing a BLA for Descartes-08 in MG in mid-2027. The company is also developing the therapy in myositis, including dermatomyositis and anti-synthetase syndrome.
Reference
Cartesian Therapeutics Announces Additional Retreatment Data for Descartes-08 Highlighting Deep and Durable Responses in Patients with Myasthenia Gravis, Cartesian Therapeutics, 29 September 2026
Descartes-08 CAR-T Cells in Generalized Myasthenia Gravis (MG), ClinicalTrials.gov ID NCT04146051
About the Writer
Creola Gonsalves (Linkedin) is an M.S. Biotechnology postgraduate with a strong interest in clinical research, evidence interpretation, and healthcare writing, with a focus on translating life-science knowledge into meaningful real-world insights.
She is trained in Good Clinical Practice (GCP), clinical research principles, and critical interpretation of randomized clinical trials, with certifications from NIH and Stanford University.
Her research background in biotechnological applications and microbial research strengthens her ability to understand scientific evidence and develop clear, accurate, and research-driven healthcare content.