NEW YORK, NY and WALTHAM, Mass. — Dianthus Therapeutics, Inc. (Nasdaq: DNTH), a clinical-stage biotechnology company dedicated to developing next-generation therapies to transform the treatment of severe autoimmune diseases, today announced initiation of the Phase 3 EMERGE trial of claseprubart in generalized Myasthenia Gravis (gMG).
“Given the impressive Phase 2 MG results, the medical team has been eagerly anticipating the initiation of this important study and the opportunity to implement important Phase 2 learnings,” said Simrat Randhawa, M.D., Executive Vice President and Head of R&D of Dianthus Therapeutics. “Our internal enthusiasm has been matched by site and principal investigator interest globally so far.”
EMERGE is a global, randomized, multicenter, placebo-controlled Phase 3 trial in approximately 195 participants with generalized Myasthenia Gravis who are acetylcholine receptor antibody positive (AChR+). Following an initial loading dose, claseprubart 300mg/2mL will be administered every two or four weeks (Q2W or Q4W) via subcutaneous (S.C.) injection. The primary endpoint of this trial is the change from baseline in the Myasthenia Gravis Activities of Daily Living Scale (MG-ADL) in the treatment arms vs. the placebo arm. A similar evaluation is used for secondary efficacy endpoints such as the Quantitative Myasthenia Gravis (QMG) scale, Minimal Symptom Expression (MSE), Myasthenia Gravis Composite (MGC) Score and the Myasthenia Gravis Quality of Life Scale (MG-QoL-15r). Top-line results from this trial are anticipated to be available in 2H’28.
Results from the MaGic trial, a global, randomized, double-blind, placebo-controlled Phase 2 trial in patients with gMG who are acetylcholine receptor (AChR) antibody positive, were reported in September 2025 and presented at the Myasthenia Gravis Foundation of America (MGFA) Scientific Session held during the 2025 American Association of Neuromuscular and Electrodiagnostic Medicine (AANEM) Annual Meeting. Claseprubart 300mg/2mL Q2W S.C. demonstrated rapid, sustained, statistically significant and clinically meaningful improvements over placebo as measured by both MG-ADL and QMG, including at Week 1 and at Week 13. The claseprubart 300mg/2mL Q2W dose was also statistically significant and clinically meaningful across other key efficacy endpoints, including MSE, MGC and MG-QoL-15r. Claseprubart was generally well tolerated with no drug-related Serious Adverse Events (SAEs) or discontinuations due to any related adverse event.
About Claseprubart (DNTH103)
Claseprubart is an investigational, clinical-stage, potent monoclonal antibody engineered to selectively target the classical pathway by inhibiting only the active form of the C1s protein, a clinically validated complement target. Claseprubart is enhanced with YTE half-life extension technology designed to enable a more convenient subcutaneous, infrequently dosed, self-administered injection. Additionally, selective inhibition of the classical complement pathway may lower patient risk of infection from encapsulated bacteria by preserving immune activity of the lectin and alternative pathways. As the classical pathway plays a significant role in disease pathology, claseprubart has the potential to be a best-in-disease pipeline-in-a-product across a range of autoimmune disorders with high unmet need. Claseprubart was granted Orphan Drug Designation by the FDA for the treatment of Myasthenia Gravis in May 2026.
Dianthus is building a neuromuscular franchise with claseprubart and expects to report top-line data from the Phase 2 MoMeNtum trial in Multifocal Motor Neuropathy in Q4’26, to provide an update on timing of top-line data from Part B of the Phase 3 CAPTIVATE trial in Chronic Inflammatory Demyelinating Polyneuropathy by YE’26, and to report top-line results from the Phase 3 EMERGE trial in generalized Myasthenia Gravis in 2H’28.
Claseprubart is an investigational agent that is not approved as a therapy in any indication in any jurisdiction worldwide.
About Generalized Myasthenia Gravis
Generalized Myasthenia Gravis (gMG) is a chronic autoimmune disorder driven by the classical pathway that causes progressive muscle weakness. Over 100,000 people in the U.S. are living with gMG and approximately 85% have AChR autoantibody-driven disease. Despite availability of current treatment options, a significant number of patients remain uncontrolled and are seeking better treatment options which may offer sustained efficacy, lower potential risk for infections, and convenient dosing and administration.
About Dianthus Therapeutics
Dianthus Therapeutics, Inc. is a clinical-stage biotechnology company dedicated to developing next-generation therapies to transform the treatment of severe autoimmune diseases. Based in New York City and Waltham, Mass., Dianthus is comprised of an experienced team of biotech and pharma executives who aim to deliver transformative medicines for people living with severe autoimmune and inflammatory diseases.
To learn more, please visit www.dianthustx.com and follow us on LinkedIn.
Contact
Jennifer Davis Ruff
Dianthus Therapeutics
[email protected]