On September 13, 2022 Rubius Therapeutics, Inc. (Nasdaq: RUBY), a biopharmaceutical company that is developing an entirely new class of cellular medicines called Red Cell Therapeutics for the treatment of cancer and autoimmune diseases, reported plans to restructure the Company and align resources to advance its next generation red blood cell-based cell conjugation platform (Press release, Rubius Therapeutics, SEP 13, 2022, View Source [SID1234619497]).

Schedule your 30 min Free 1stOncology Demo!
Discover why more than 1,500 members use 1stOncology™ to excel in:

Early/Late Stage Pipeline Development - Target Scouting - Clinical Biomarkers - Indication Selection & Expansion - BD&L Contacts - Conference Reports - Combinatorial Drug Settings - Companion Diagnostics - Drug Repositioning - First-in-class Analysis - Competitive Analysis - Deals & Licensing

                  Schedule Your 30 min Free Demo!

"With more than 80 patients dosed across three clinical trials to date, Rubius Therapeutics has demonstrated that engineered red blood cells can be manufactured at scale, safely administered and activate a patient’s immune system, resulting in clinical benefit in certain cancer patients, including evidence of tumor shrinkage and prolonged stable disease in PD-(L)-1 refractory solid tumors," said Pablo J. Cagnoni, M.D., president and chief executive officer of Rubius Therapeutics. "Based on these early findings, we firmly believe in the potential of Red Cell Therapeutics for the treatment of cancer and autoimmunity. Following careful review of recent technical progress in an alternative format for making Red Cell Therapeutics, we believe that this process has the potential for substantive improvements over our existing platform, and, therefore, continued investment in our two current clinical candidates is no longer justified. Instead, we plan to focus on advancing a next generation red blood cell platform that utilizes cell conjugation to potentially improve upon the existing benefits of the RED PLATFORM, with the potential for greater efficacy and enhanced versatility, while maintaining our favorable tolerability profile. As a result, we have decided to discontinue our ongoing clinical trials of RTX-240 and RTX-224 for the treatment of advanced solid tumors and restructure the organization to support advancing drug candidates based on the next generation platform. I would like to express my sincere gratitude to the patients who participated in our clinical trials, the investigators who partnered with us in this endeavor and our employees for their immense dedication and contributions that have brought us to where we are today."

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.

Overview of Current Clinical Programs

Phase 1 Clinical Trial of Monotherapy RTX-240

As of September 12, 2022, 36 patients have been dosed in the monotherapy arm of the Phase 1/2 clinical trial of RTX-240 in advanced solid tumors. One patient with renal cell carcinoma remains on study with stable disease for more than one year after developing progressive disease on prior treatment with nivolumab. This ongoing patient was dose-escalated from the 3e10 x 3 + 1e10 Q3W dose level (n=6) to the 5e10 Q3W dose level after Cycle 12. Seven patients were dosed at 5e10 Q3W with one anal cancer patient experiencing stable disease for 5 months before disease progression. RTX-240 continued to be well tolerated with no treatment-related Grade 3/4 adverse events (AEs) and no dose-limiting toxicities.

Phase 1 Clinical Trial of RTX-240 + Pembrolizumab in Advanced Solid Tumors

Fourteen patients were dosed in the "all comers" dose-escalation portion of the Phase 1 clinical trial evaluating RTX-240 in combination with pembrolizumab in advanced solid tumors. Four patients had stable disease of greater than 12 weeks with one colorectal cancer patient remaining on study with stable disease of greater than 4 months. Two additional patients have been dosed in the non-clear cell RCC (nccRCC) and non-small cell lung cancer (NSCLC) expansion cohorts. Both patients remain on treatment with one nccRCC patient with stable disease greater than 12 weeks and one NSCLC patient who is not yet evaluable for response. The combination of RTX-240 with pembrolizumab continued to be well tolerated with no treatment or investigator-identified immune-related Grade 3/4 AEs and no dose-limiting toxicities.

Phase 1 Clinical Trial of RTX-224 in Select Advanced Solid Tumors

Seven patients have been dosed across two dose cohorts in the Phase 1 clinical trial evaluating RTX-224 in select advanced solid tumors, including non-small cell lung cancer, cutaneous melanoma, head and neck squamous cell carcinoma, urothelial (bladder) carcinoma and triple-negative breast cancer. One patient dosed at the 5e8 Q3W dose level with melanoma remains on study and is not yet evaluable for response. There have been no treatment-related Grade 3/4 AEs and no dose-limiting toxicities.

Investor Teleconference & Webcast

An audio webcast will be available on the Events and Presentations page within the Investors and Media section of the Rubius Therapeutics website and can be directly accessed here. An archived webcast will be accessible for 90 days after the event.