Sobi showcased new clinical data across its immunology portfolio at the American College of Rheumatology (ACR) Convergence 2025 meeting in Chicago, presenting findings that could advance treatment options for patients with rare inflammatory conditions. The global biopharmaceutical company presented 15 scientific abstracts, with six oral presentations featuring new clinical data from completed and ongoing studies.
"The data Sobi is presenting highlight the distinct clinical benefit of emapalumab-lzsg in MAS in Still's disease, the ongoing study of pacritinib in VEXAS Syndrome, and the potential for NASP to redefine the treatment of uncontrolled gout," said Lydia Abad-Franch, MD, Head of R&D and Medical Affairs, and Chief Medical Officer at Sobi. "The results underscore the strength of our portfolio in advancing care for complex and rare inflammatory diseases where progress is urgently needed."
Novel Approach to Uncontrolled Gout Treatment
NASP represents a novel investigational medicine designed to reduce serum uric acid (sUA) levels in people living with uncontrolled gout. The treatment aims to reduce harmful tissue urate deposits which, when left untreated, can lead to debilitating gout flares and joint deformity.
The therapy is administered every four weeks as a sequential, two-component infusion therapy. It consists of tolerogenic nanoencapsulated sirolimus (NAS), which mitigates the formation of anti-drug antibodies (ADAs), and a uricase called pegadricase (P), which reduces serum uric acid. This approach addresses a significant challenge in biologic medicine, as ADAs develop due to unwanted immune responses to biologic medicines, reducing their efficacy and tolerability across multiple therapeutic modalities and disease states.
Gout affects more than 8.3 million people in the United States and is the most common form of inflammatory arthritis. Approximately 200,000 people in the United States suffer from uncontrolled gout, with serum uric acid levels above 6 mg/dL despite treatment with oral urate lowering therapies, leading to debilitating flares and tophi formation.
Advances in Macrophage Activation Syndrome Treatment
Sobi presented new data on Gamifant (emapalumab-lzsg), the only approved anti-interferon gamma (IFNγ) monoclonal antibody. The treatment works by binding to and neutralizing interferon gamma, addressing the hyperinflammation that occurs when IFNγ is secreted in an uncontrolled manner.
Gamifant is approved in the US for treating adult and pediatric patients with primary hemophagocytic lymphohistiocytosis (HLH) with refractory, recurrent or progressive disease or intolerance with conventional HLH therapy. It is also approved for treating patients with HLH/macrophage activation syndrome (MAS) in known or suspected Still's disease with inadequate response or intolerance to glucocorticoids, or with recurrent MAS.
MAS is a severe complication of rheumatic diseases, most frequently occurring in Still's disease including systemic juvenile idiopathic arthritis (sJIA). This rare systemic disorder presents with daily spiking fever, typical transient cutaneous rash, arthritis, lymphadenopathy, hepatosplenomegaly and serositis. MAS is characterized by fever, hepatosplenomegaly, liver dysfunction, cytopenias, coagulation abnormalities and hyperferritinaemia, and can progress to multiple organ failure and death.
VEXAS Syndrome Research Progress
The company also presented ongoing study data for pacritinib in VEXAS syndrome. Vonjo (pacritinib) is a kinase inhibitor currently indicated in the US for treating adults with intermediate or high-risk primary or secondary myelofibrosis with a platelet count below 50 × 10⁹/L. This indication was approved under accelerated approval based on spleen volume reduction.
VEXAS syndrome causes inflammatory and hematologic manifestations and is caused by mutations in the UBA1 gene of blood cells acquired later in life. The condition is not genetically inherited, making it a distinct target for therapeutic intervention.
The comprehensive data presentation at ACR 2025 demonstrates Sobi's commitment to developing treatments for rare inflammatory diseases. With approximately 1,900 employees across Europe, North America, the Middle East, Asia and Australia, and 2024 revenue of SEK 26 billion, Sobi continues to focus on unlocking breakthrough innovations for patients with rare diseases.
