Clinical Update of Ongoing Investigator-Initiated Studies of RXIM002
Aug 9, 2026
RXIM002, developed by RiboX Therapeutics, is an investigational product employing tLNP encapsulated circRNA that encodes a CD19 targeting chimeric antigen receptor (CAR), and achieved FDA IND clearance for the treatment of autoimmune cytopenias. By delivering circRNA to T cells in vivo, RXIM002 enables durable CAR expression and generating functional CAR-T cells directly within the patient's body.
Prior to the IND submission, RXIM002 was evaluated in two independent investigator-initiated trials (IITs) in China in autoimmune disease patients. Follow-up of these patients are currently ongoing, with some patients exceeding six months. RiboX submitted complete IIT data as part of the IND package to the FDA, encompassing safety and early efficacy results from all treated patients.
Safety and Tolerability
RXIM002 demonstrated an acceptable tolerability profile across the dose levels and routes of administration. No Dose-Limiting Toxicities (DLT), or treatment interruptions were reported in patients treated under protocol-defined safeguards. The safety profile is consistent with on-target pharmacology and previously reported CAR-T class effects. Low grade CRS was observed and manageable without advanced interventions.
A single fatal serious adverse event (SAE) occurred at the 2nd site in one participant with systemic sclerosis, with significant pre-existing medical conditions. As part of standard IND submission process, the complete data from the investigator-initiated studies, including information regarding this event, were provided to the applicable regulatory authority.
Preliminary Efficacy Observations
Upon single dose administration of RXIM002, a durable clinical improvement has been observed in all treated patients enrolled in stringent compliance with study protocol. In a subgroup of patients, treatment of RXIM002 induced durable remission over several months. These findings align with the emerging clinical profile of CD19-targeted therapies in autoimmune indications, suggesting that RXIM002 can induce meaningful clinical responses in this heavily pretreated population. Further follow-up of the current cohort and expansion of the study under reinforced oversight are warranted to confirm these findings and establish the durability of response.
Patient safety remains our highest priority. The study is proceeding as planned. Further updates of the study will be disclosed in the upcoming medical conferences and/or publications.
Forward-Looking Statements
This press release contains forward-looking statements regarding the development, regulatory advancement, clinical evaluation, safety, efficacy, and commercial potential of RXIM002 and the Company's circular RNA and targeted lipid nanoparticle platforms. Actual results may differ materially due to various risks and uncertainties. RiboX undertakes no obligation to update forward-looking statements except as required by law.