Cambridge, Mass. — RiboX Therapeutics said the U.S. Food and Drug Administration has cleared its Investigational New Drug application for RXIM002, allowing the company to begin a Phase 1 clinical trial of the experimental therapy for autoimmune cytopenias.
RXIM002 uses targeted lipid nanoparticles to deliver circular RNA encoding a CD19-targeting chimeric antigen receptor directly to T cells inside the body. RiboX said the approach is designed to generate functional CAR-T cells in vivo rather than requiring the collection and external manufacturing of a patient’s cells.
The company said RXIM002 is the first circular RNA-based in vivo CAR therapy to receive FDA IND clearance.
Conventional CAR-T therapies typically require cells to be removed from a patient, genetically modified and expanded before being infused back into the body. RiboX’s approach is intended to eliminate much of that manufacturing process by producing CAR-T cells directly within the patient.
RXIM002 is being developed for autoimmune cytopenias. The therapy targets CD19-positive B cells, with the goal of achieving deep B-cell depletion and potentially resetting immune function.
Before submitting the IND application, RiboX evaluated RXIM002 in investigator-initiated studies involving patients with autoimmune diseases in China. The company said it submitted safety and preliminary efficacy data from all treated patients to the FDA as part of the application.
RiboX said the agency permitted an accelerated dose-titration plan and allowed a subcutaneous formulation to be evaluated in clinical development. The company said subcutaneous administration could eventually support outpatient treatment if the therapy proves safe and effective.
“The FDA IND clearance for RXIM002 is a pivotal milestone for RiboX and for the field of circRNA medicines,” said Weiyi Zhang, Ph.D., Chief Executive Officer of RiboX Therapeutics.
Zhang said the company plans to advance clinical development of RXIM002 in multiple regions as it evaluates the therapy for autoimmune diseases.
The clearance also expands RiboX’s clinical-stage pipeline based on its proprietary targeted lipid nanoparticle delivery technology and engineered circular RNA platform.
