METiS TechBio's enters MTS109 into Phase I for refractory autoimmune disease

Shanghai Changzheng Hospital has opened enrollment in the first-in-human clinical trial ([NCT07526350](https://clinicaltrials.gov/study/NCT07526350)) evaluating an mRNA-encoded, lipid nanoparticle–delivered chimeric antigen receptor (CAR) therapy in patients with moderate to severe refractory autoimmune disease. The MTS109 investigational drug was developed by METiS TechBio, a Hangzhou- and Beijing-based company. Based on the study’s pharmacodynamic endpoints and exclusion criteria (excluding patients previously treated with CAR-T or B-cell targeted therapies) the therapy appears to target B cells, potentially via CD19, although this has not been explicitly disclosed. If confirmed, MTS109 could represent an early clinical example of an in vivo CAR-T approach delivered by subcutaneous injection for systemic autoimmune conditions, bypassing the ex vivo cell manufacturing required for conventional CAR-T therapies. The Phase I FIH clinical trial is open-label and single-arm, enrolling up to 15 adults aged 18 to 65 with refractory systemic lupus erythematosus, idiopathic inflammatory myopathies, systemic sclerosis, ANCA-associated vasculitis, or Sjögren's syndrome. All participants must have failed conventional immunosuppressive therapy for at least six months and meet disease-specific activity thresholds. Primary endpoints assess the rate of treatment-emergent adverse events and the proportion of participants experiencing grade 3 or higher adverse events within 28 days of the last dose. Primary completion is expected in Q2 2028, with full study completion targeted for Q2 2029. MTS109 is understood to encode a CAR construct delivered via lipid nanoparticles, enabling transient in vivo expression following subcutaneous administration. The approach reflects a broader effort to replicate the mechanism of ex vivo CAR-T therapies in autoimmune disease using an in vivo delivery model, in which transient CAR expression may mitigate risks associated with permanent genomic integration while still enabling immune reset. METiS TechBio appears to have generated MTS109 through its internal platforms, including AiLNP for lipid nanoparticle design and AiRNA for mRNA optimization. The program sits within a nascent field of in vivo CAR-T approaches for autoimmune disease, where most clinical experience to date has been generated using ex vivo CD19-directed CAR-T therapies that require cell extraction, engineering, and reinfusion. --- Spot something wrong? [Report an issue with this article](https://newsgen-prod.reframedata.com/feedback/mrna-car-t-therapy-autoimmune-metis-techbios)