RheumaGen Unveils Universal HLA Gene-Editing Approach for Autoimmune Disease Treatment
Key Insights
RheumaGen (search) presented groundbreaking preclinical data at ACR Convergence 2025 demonstrating a novel "anchor-position editing" approach that targets a nearly universal HLA (search) amino acid position to treat autoimmune diseases (search).
The company's innovative gene-editing technique modifies only one amino acid at position 82 of HLA (search) molecules, successfully blocking three critical self-peptides in rheumatoid arthritis (search) from being presented to T cells.
This universal targeting approach could potentially treat multiple autoimmune diseases (search) across different patient demographics while avoiding the broad immune suppression associated with current biologics.
RheumaGen (search), a Colorado-based cell and gene therapy company, has announced groundbreaking preclinical research that could revolutionize autoimmune disease treatment through a novel "anchor-position editing" approach targeting human leukocyte antigen (search) (HLA (search)) molecules. The data, presented at the American College of Rheumatology (ACR) Convergence 2025 in Chicago, demonstrates a nearly universal target for HLA gene-editing therapies that could treat multiple autoimmune diseases (search) across diverse patient populations.
Revolutionary Anchor-Position Editing Technology
The company's innovative approach focuses on editing a single amino acid at position 82 of HLA (search) molecules, a strategy that represents a significant departure from previous methods requiring individual gene edits for specific patient demographics. According to Dr. Brian Freed, Chief Science Officer and Co-Founder of RheumaGen (search), "Nearly every person has the same amino acid, asparagine, at position 82 of their HLA molecule. When a non-polar amino acid, like leucine, is substituted at that position, it breaks the hydrogen bond and effectively acts like a zipper – failing to connect at the bottom, it cannot zip up."
This precise modification substantially reduces self-peptide binding and T-cell presentation for the selected allele. The preclinical data presented by Dr. Vibha Jha from the University of Colorado Anschutz Medical Campus (search) demonstrated that anchor-position editing successfully blocks three of the most critical self-peptides in rheumatoid arthritis (search) – both citrullinated peptides and collagen – from being presented to T cells.
Targeting the Strongest Genetic Risk Factor for Rheumatoid Arthritis
RheumaGen (search)'s lead asset, RG0401, specifically targets HLA-DRB1*04:01 (search), identified as the strongest genetic risk factor for rheumatoid arthritis (search). The research shows that this approach has the potential to safely halt disease progression in patients carrying this allele variant. Unlike current treatments that broadly suppress the immune system, RheumaGen's method selectively targets only the source of autoimmune disease.
"RheumaGen (search) only targets the source of autoimmune disease and selectively quiets one of the 10 or 14 alleles fueling immunity," explained Dr. Freed. "This approach contrasts sharply with the current standard of care, such as biologics or other drugs, that globally suppress a patient's immune system."
Safety Profile and Mechanism of Action
The safety profile of RheumaGen (search)'s approach is rooted in the natural polymorphic nature of the HLA (search) gene system. Every person possesses 10-14 HLA alleles, providing extensive overlapping immune protection. By targeting only one problematic allele while leaving the others intact, the therapy maintains immune function while addressing the root cause of autoimmune disease.
Dr. Freed noted that "allogeneic transplants can cure autoimmunity," but previous approaches were not safe enough due to immunogenicity and rejection risks. "RheumaGen (search)'s potential innovation is that we have introduced the minimal amount of alloreactivity to still significantly mediate – or in fact, cease – the disease."
Broad Therapeutic Pipeline and Commercial Implications
Beyond rheumatoid arthritis (search), RheumaGen (search) is advancing a pipeline of treatment candidates for multiple autoimmune diseases (search) where HLA (search) alleles play critical epidemiological roles, including multiple sclerosis (search), type 1 diabetes (search), celiac disease (search), and ankylosing spondylitis (search). The universal nature of the anchor-position editing approach could significantly streamline development across these indications.
"HLA (search) anchor-position editing unlocks a nearly universal target across almost all our indications," said Richard Freed, CEO and Co-Founder of RheumaGen (search). "The commercial, regulatory, and accessibility implications of this target are significant. RheumaGen is part of the next wave of CGT companies systematically solving for the industry's challenges, and our differentiated HLA gene-editing approach has the potential to create durable, one-time therapies for chronic autoimmune diseases (search) that could help millions of patients and their families."
Industry Impact and Future Implications
The discovery represents a potential paradigm shift in autoimmune disease treatment, moving from chronic management to potential cures through one-time gene therapy interventions. Richard Freed emphasized the broader industry significance: "The discovery of anchor-position editing and the related preclinical data will be a game-changer, not only for RheumaGen (search), but also ultimately for our cell and gene therapy (CGT) industry."
The research was conducted in partnership with the ClinImmune Center for Clinical Immunology (search) at the University of Colorado Anschutz Medical Campus (search), which operates a 25,000-square-foot cGMP facility and has facilitated more than 10,000 organ and stem-cell transplants since its founding in 1997.