AbolerIS Pharma Advances Novel Anti-CD45RC Antibody ABO21009 to Patient Testing in Rheumatoid Arthritis Phase 1 Trial
Key Insights
AbolerIS Pharma (search) has dosed the first patient with ABO21009 (search), a first-in-class humanized anti-CD45RC monoclonal antibody (search), in Part II of its Phase 1 study for rheumatoid arthritis (search) treatment.
The novel therapy works through a unique mechanism that selectively depletes pathogenic effector T and B cells while preserving regulatory T cells to restore immune tolerance.
The ongoing adaptive Phase 1 study includes three parts: healthy volunteer dosing (completed with 24 participants), single ascending dosing in RA patients, and multiple ascending dosing in RA patients.
AbolerIS Pharma (search) has achieved a significant milestone in autoimmune disease treatment by dosing the first patient with ABO21009 (search), a novel humanized anti-CD45RC monoclonal antibody (search), in Part II of its ongoing Phase 1 study for rheumatoid arthritis (search) (RA). This advancement marks the company's transition from healthy volunteer evaluation to patient dosing, representing a critical step toward establishing clinical proof-of-concept for this first-in-class immunomodulatory therapy.
The Belgian-French biopharmaceutical company designed ABO21009 (search) to address a persistent unmet medical need in autoimmune disease management. Despite significant advances in RA treatment, many patients fail to achieve durable remission and suffer from treatment-related side effects. ABO21009 was developed as a curative-intent therapy that induces an immune reset and restores immune tolerance.
Novel Mechanism Targets Disease Drivers
ABO21009 (search) operates through a multi-pronged mechanism of action that selectively depletes CD45RC (search)-positive cells actively sustaining the autoimmune response in rheumatoid arthritis (search). These pathogenic cells are present in the T-, B-, and NK-cell compartments of the adaptive immune system. By selectively removing these disease-driving cells from the immune cell population, the therapy aims to address the underlying causes rather than merely managing symptoms.
Crucially, the treatment spares regulatory T cells, allowing them to unleash their full potential and suppress ongoing and future autoimmune activity in the adaptive immune system. This selective approach is designed to preserve overall immunity while targeting the specific cells responsible for autoimmune pathology.
"ABO21009 (search) is the first antibody of its class and represents an entirely new way to reset the immune system and restore immune tolerance," said Dr. Ronald Van Brempt, Chief Medical Officer of AbolerIS Pharma (search). "ABO21009 targets the underlying drivers of disease that are currently preventing a transition from remission to cure."
Comprehensive Phase 1 Study Design
The ongoing Phase 1 study employs a first-in-human, adaptive design, randomized, single-blind, placebo-controlled dose escalation approach with three distinct parts. Part I involved single ascending dosing in healthy volunteers, where 24 participants were enrolled and received one of four single doses of ABO21009 (search), with follow-up extending up to 10 weeks.
The study has now progressed to Part II, focusing on single ascending dosing in patients with RA, currently enrolling and dosing patients in the Netherlands. Part III will evaluate multiple ascending dosing in RA patients. The comprehensive design aims to evaluate safety, tolerability, pharmacokinetics, and pharmacodynamics of ABO21009 (search) across different dosing regimens and patient populations.
Potential for Paradigm Shift
Dr. Ann Meulemans, CEO of AbolerIS Pharma (search), emphasized the significance of this milestone: "Dosing the first patient in our Phase 1 study represents a major step forward for AbolerIS and our mission to redefine the treatment of autoimmune disease, including in RA where patients are in need of new options."
The company believes treatment with ABO21009 (search) may enable long-lasting and durable remission in RA, potentially improving the patient experience and lessening the burden of side effects from currently available therapeutic options. This approach represents a shift from chronic disease management to potentially curative therapy.
Broader Development Strategy
AbolerIS Pharma (search), based in Gosselies, Belgium, and Nantes, France, is advancing ABO21009 (search) as its lead program in a broader pipeline of potentially best-in-class and first-in-class immunomodulatory antibodies targeting CD45RC (search). Pending clinical proof-of-concept in RA, the company intends to expand development into other autoimmune diseases (search), including inflammatory bowel disease and organ transplantation applications.
The company is backed by a syndicate of experienced investors, including Newton Biocapital, Criteria Bio Ventures, Invested Tech, Sound Bioventures, WE, Sambrinvest, SFPIM, and Sham Innovation Santé, providing the financial foundation for continued clinical advancement of this novel therapeutic approach.