Oral presentation at ACR Convergence uncovers the role of the CD40 pathway in myositis and potential therapeutic benefit of ABX1200, a novel CD71-Centyrin CD40-siRNA conjugate
PHILADELPHIA, Nov. 10, 2026 (GLOBE NEWSWIRE) -- Aro Biotherapeutics, a clinical-stage biotechnology company developing potent and tissue-targeted short-interfering RNA (siRNA) medicines, presented studies in collaboration with the Karolinska Institute showing evidence for the role of the CD40/CD40L pathway in myositis. The company also presented preclinical data showing that ABX1200, a CD71-Centyrin CD40-siRNA conjugate, reduces CD40 expression, which may offer a potential approach for treating inflammatory myositis. The findings were presentated today in an oral presentation at ACR Convergence 2026, the American College of Rheumatology’s annual meeting, in Orlando, FL.
“Having our study selected for an oral presentation at ACR 2026 is a recognition of the scientific importance behind our collaboration with Aro Biotherapeutics,” noted Dr. Ingrid Lundberg, Professor of Rheumatology at the Karolinska Institute. “Partnerships between academia and industry play a key role in advancing innovation for patients with rheumatic diseases. Because myositis is a muscle disease, patients stand to benefit from the development of muscle-targeted therapies like ABX1200, and this collaboration has taken steps to advance this approach.”
To explore the role of CD40/CD40L in idiopathic inflammatory myopathies (IIM), patient muscle samples were analyzed by RNA sequencing (RNAseq) and immunohistochemistry (IHC). RNAseq analysis demonstrated elevated CD40 expression in the muscle of inclusion body myositis (IBM) patients, and predominant CD40L expression in CD4+ central memory T cells in blood, as well as in T cells infiltrating the muscle of myositis patients. IHC showed CD40 co-expression with muscle infiltrating macrophages. Importantly, CD40 expression in the myositis patient samples correlated with high serum creatine kinase (CK) levels and disease activity scores, supporting the rationale for targeting this pathway with ABX1200 and highlighting a key proof of principle for its proposed mechanism of action. To study the effect of targeting this pathway in myositis, CD40 mRNA was knocked down by ABX1200, both in vitro and in a preclinical model of muscle inflammation. ABX1200 reduced expression of CD40 mRNA in vitro in both macrophages and myotubes, and in vivo ABX1200 reduced the upregulation of CD40 and chemokines that are upregulated in IIM patients.
"These data provide evidence that ABX1200 may represent a promising approach for inflammatory myositis patients. The Centyrin platform is designed for targeting both skeletal muscle and inflammatory leukocytes, aiming to effectively deliver CD40 siRNA and directly address the pathogenicity of the disease," said Purnanand Sarma, CEO of Aro Biotherapeutics. "We are planning to begin clinical studies in 2027."
ABX1200 is an investigational therapy and has not been evaluated for safety or efficacy by any regulatory authority. This press release contains forward-looking statements, including statements regarding the planned initiation of clinical studies in 2027. These statements involve risks and uncertainties, and actual results may differ materially.
About Myositis
Myositis, also known as idiopathic inflammatory myopathy (IIM), is a group of autoimmune diseases in which the immune system attacks skeletal muscle, causing chronic inflammation. Over time this leads to progressive muscle weakness and, in some cases, muscle pain. Myositis most often affects muscles of the arms, shoulders, thighs and hips, and can also involve muscles needed for swallowing and breathing. Other symptoms can include fatigue, joint pain, swelling, and, in dermatomyositis, a skin rash. Major forms include dermatomyositis, anti-synthetase syndrome, immune-mediated necrotizing myopathy, and inclusion body myositis. The causes are not fully understood, and there is no cure. Treatment focuses on managing symptoms and reducing inflammation, most commonly with corticosteroids, immunosuppressants and intravenous immunoglobulin, together with physical therapy.
About Aro Biotherapeutics
Aro Biotherapeutics is a biotechnology company working to develop potent and versatile tissue-targeted short-interfering RNA (siRNA) medicines for the treatment of immune-mediated diseases and diseases with high unmet medical need. The company is developing a wholly owned pipeline of therapeutic candidates for a diverse set of diseases, employing a proprietary protein technology called Centyrins, which are small proteins engineered for exceptional efficiency, versatility, and safety. For more information, visit https://www.AroBiotx.com/.
Contact:
Katrina Comber
KComber@arobiotx.com
215-544-1183
