RESTEM Unveils Phase 1 ULSC Data in Polymyositis/Dermatomyositis at ACR Convergence 2024

RESTEM, a clinical-stage biotechnology company based in Miami, Florida, has unveiled promising data from its Phase 1 trial of umbilical cord outer lining-derived stem cells (ULSCs) in adults with Polymyositis (PM) and Dermatomyositis (DM). Presented at the American College of Rheumatology's (ACR) annual meeting, ACR Convergence 2024, the results highlight the potential of ULSCs in treating these debilitating inflammatory myopathies, now classified by the FDA as Idiopathic Inflammatory Myopathy (IIM).

Polymyositis and Dermatomyositis are severe autoimmune conditions that cause muscle inflammation and weakness, severely affecting patients' quality of life. Treatments have traditionally relied on steroids and immunosuppressive drugs, which often bring substantial side effects. The new data from RESTEM's Phase 1 trial offers hope for safer and more effective alternatives.

Dr. Michael R. Bubb of University of Florida Health Rheumatology presented the findings titled, “Safety and Efficacy Data from a Phase I Trial of Umbilical Lining Stem Cells (ULSCs) in Adult Dermatomyositis/Polymyositis.” The trial results indicate that ULSCs were well tolerated by patients and led to significant clinical improvements.

Among the nine patients enrolled in the study, seven demonstrated notable clinical improvements, with an average total improvement score (TIS) in the 30-35% range sustained over a year. Clinically significant improvement, defined by a TIS of ≥20%, was observed in 78% of the participants, and 67% showed moderate improvement with a TIS of ≥40%. These results were accompanied by a substantial reduction in steroid use, with an average decrease of 35% in six months, offering a promising outlook for reducing drug-related side effects.

Additionally, manual muscle testing (MMT8) results showed a nearly 10-point improvement in muscle strength from baseline to six months. The average prednisone dosage was reduced by almost 50% in daily users, excluding one non-responder who experienced a flare-up during the trial.

Rafael Gonzalez, Ph.D., Chief Development and Science Officer at RESTEM, expressed optimism about the findings. He emphasized the urgent need for safer treatments for PM and DM, considering the severe side effects associated with current therapies. He noted that ULSCs not only demonstrated safety and tolerability but also showed potential in reducing inflammation by modulating the immune system.

Dr. Jonathan Krant, Chairman of Rheumatology for Monadnock Health Systems, highlighted the broad implications these findings could have for PM/DM patients. If validated, the reduction in steroid use could significantly impact current treatment protocols.

The Phase 1 trial involved an open-label, dose-escalation study with a single intravenous infusion of ULSCs, examining three different dose levels (50, 100, and 200 million ULSCs) in nine patients over a 12-month follow-up period. A single adverse event of a flushing reaction was reported, which was managed effectively, reaffirming the treatment's safety.

Based on these encouraging Phase 1 results, RESTEM plans to initiate a Phase 2/3 trial in the first quarter of 2025, establishing the dose at 100 million ULSCs. This advancement signifies a significant step forward in developing next-generation cell therapies aimed at modulating the immune system to treat auto-immune diseases. RESTEM's innovative approach and robust clinical development capabilities continue to drive progress in the field of cell therapy, with the potential to transform treatment paradigms for disabling diseases like Polymyositis and Dermatomyositis.