Rubius Therapeutics, Inc. announced plans to restructure the Company and align resources to advance its next generation red blood cell-based cell conjugation platform. Next Generation Red Blood Cell-Based Conjugation Platform Overview The new platform is expected to improve upon the existing benefits of the RED PLATFORM, with the potential for greater efficacy and enhanced versatility, while maintaining a favorable tolerability profile, and reduce the complexity and cost of generating cells by leveraging chemical conjugation to produce Red Cell Therapeutics. Cell conjugation creates a covalent link between the cell surface and the molecule of interest.

This approach is intended to: deliver a higher effective dose by enabling a longer circulation time and/or administering a higher cell dose;be more versatile, enabling the conjugation of different payloads, immunomodulatory agents, small molecules and proteins on the cell for enhanced potency; and reduce the cost of goods manufacturing by utilizing blood-banked RBCs versus biologically engineering and differentiating early progenitor cells into reticulocytes that express proteins. These attributes are expected to result in greater efficacy, a similar safety profile given the restricted biodistribution of RBCs to the spleen and vasculature and a significant reduction in overall cost structure. Business & Strategy Update: To enable continued investment in the new platform, the Company is restructuring its business and implementing a series of cost-saving measures, which extends the Company's cash runway until the end of 2023.

These measures include Implementing a 75% reduction in force, primarily focused on clinical development, manufacturing and general and administrative; Discontinuing its ongoing Phase 1 clinical trials of RTX-240 and RTX-224 for the treatment of advanced solid tumors; and Exploring the sale of its manufacturing facility in Smithfield, Rhode Island Patients still on trial will continue to be dosed until disease progression or discontinuation (n=6). The Company will maintain its robust technical development and preclinical oncology and autoimmunity research capabilities to advance the new platform and related preclinical programs.