IASO Bio's Equecabtagene Autoleucel for Refractory Myasthenia Gravis (MG) Case Report Published in EMBO Molecular Medicine

SHANGHAI and NANJING, China and SAN JOSE, Calif., Feb. 29, 2024 /PRNewswire/ -- On February 26, 2024, the impactful international academic journal, EMBO Molecular Medicine, published the clinical data of the fully human BCMA targeting autologous CAR-T cell injection (Equecabtagene Autoleucel, Eque-cel, CT103A) for the treatment of two refractory myasthenia gravis (MG) subjects. B cell lineage reconstitution underlies CAR-T cell therapeutic efficacy in patients with refractory myasthenia gravis, initially demonstrated the good tolerability and safety of Eque-cel in the treatment of MG, as well as the durable clinical efficacy. 

MG is an autoimmune disease with acquired neuromuscular junction (NMJ) transmission disorders mediated by antibodies. Antibodies to the Acetylcholine Receptor (AChR) are the most common pathogenic antibodies; in addition, antibodies such as Muscle-Specific receptor tyrosine Kinase (MuSK), low-density Lipoprotein Receptor-related Protein 4 (LRP4), and Ryanodine Receptor (RyR), have also been found to be involved in the pathogenesis of MG. Currently, the treatment of MG is still based on cholinesterase inhibitors, glucocorticoids, immunosuppressants, intravenous immunoglobulin, plasma exchange, and thymectomy. The main causes of death in MG patients include respiratory failure and pulmonary infections. 

This is an investigator-initiated open-label study to evaluate the safety and efficacy of Eque-cel for the treatment of relapsed/refractory antibody-mediated idiopathic inflammatory disorders of the nervous system (NCT04561557).  It was conducted by Prof. Wei Wang's team at Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology. 

Two subjects with refractory MG were enrolled in this study. One was a 33-year-old female, AChR-IgG and Titin-IgG positive, who had been treated with thymectomy 21 months prior to enrollment and had not achieved clinical remission after treatment with cholinesterase inhibitors, glucocorticoids, immunosuppressants, and anti-CD20 monoclonal antibody. The other subject was a 60-year-old female, MuSK- IgG4 positive, with a 20-year history of the disease and failed the previous treatment with hormones, immunosuppressants, and anti-CD20 monoclonal antibody. The 2 subjects were treated with a single infusion of Eque-cel at the doses of 1.01×10⁶ CAR-T/Kg and 0.96×10⁶ CAR-T/Kg， respectively. 

Safety: Of the 2 subjects, only 1 subject developed grade 1 Cytokine Release Syndrome (CRS), and no Immune effector Cell-Associated Neurotoxicity Syndrome (ICANS). All grade ≥3 hemocytopenia recovered within 4 weeks post infusion. No new safety risk was identified, and the safety profile was superior compared to that in multiple myeloma indication. 

Effectiveness: Clinical symptoms continued to improve over 18 months in the 2 subjects. From 3 months after the infusion, patients showed significant improvement in limb strength and vital capacity, and sustained improvement in Myasthenia Gravis-Activities of Daily Living Score (MG-ADL), Quantitative Myasthenia Gravis Score (QMG), Myasthenia Gravis-Quality of Life Score (MG-QOL), and Modified Rankin Score (mRS). No immunomodulatory therapy other than low dose pyridostigmine (90 mg/day and 60 mg/day, respectively) was used during the follow-up period. 

PK/PD: Eque-cel expanded well after infusion and persisted for a shorter period than that in multiple myeloma patients. Anti-AChR antibodies, anti-Titin antibodies, and anti-MuSK antibodies decreased rapidly and maintained at very low levels in both subjects after infusion. B cells and plasma cells decreased to undetectable levels in both subjects within 2 months after infusion and then recovered gradually. At 18 months post-infusion, the B cells of both subjects had returned to normal levels, with approximately 80% of them being naïve B cells, while plasma cells remained at low levels. This result suggests that the long-term efficacy of CAR-T cell therapy may be related to the reconstitution of B cells with a predominantly naïve phenotype and the continued clearance of plasma cells. 

The principal investigator of this study, Prof. Wei Wang of Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, said "Myasthenia Gravis has a long course, is difficult to cure, and is prone to recurrence. Current treatment with traditional medications, although is able to improve symptoms of Myasthenia Gravis to a certain extent, is deficient in terms of disease control and long-term safety, and there is an urgent need for patients to have a better clinical outcome and treatment modality. In our study, it is gratifying to see that BCMA CAR-T cell therapy can prevent MG disease progression and show signs of reversal of the disease, which is expected to change the MG treatment landscape and bring hope for a cure to patients." 

In addition to the results of this published study, IASO Bio and a team of investigators continue to explore the safety and efficacy of Equecabtagene Autoleucel in the treatment of other antibody-mediated autoimmune diseases, including optic neuromyelitis optica spectrum disorders (NMOSD), Immune-Mediated Necrotizing Myelopathy (IMNM), and Chronic Inflammatory Demyelinating Polyneuropathy (CIDP), with an aim to change the landscape of treatment for autoimmune diseases. 

About IASO Bio

IASO Bio is a biopharmaceutical company engaged in the discovery and development of novel cell therapies and biologics for oncology and autoimmune diseases. IASO Bio possesses comprehensive capabilities spanning the entire drug development process, from early discovery to clinical development, regulatory approval, and commercial production.

The pipeline in the company includes a diversified portfolio of over 10 novel products, including Equecabtagene Autoleucel (a fully human BCMA CAR-T injection). Equecabtagene Autoleucel received New Drug Application (NDA) approval from China's National Medical Products Administration (NMPA) and U.S. FDA IND approval for the treatment of RRMM.

Leveraging its strong management team, innovative product pipeline, GMP production, as well as integrated manufactural and clinical capabilities, IASO aims to deliver transformative, curable, and affordable therapies that fulfil unmet medical needs to patients in China as well as around the world. For more information, please visit http://www.iasobio.com or www.linkedin.com/company/iasobiotherapeutics.

SOURCE IASO Bio