Dianthus Therapeutics Announces Positive Data for Claseprubart (DNTH103) from the Phase 2 MaGic Trial in Generalized Myasthenia Gravis, Supporting Its Potential Best-In-Class Profile
Dianthus Therapeutics (NASDAQ:DNTH) reported positive Phase 2 MaGic trial results for claseprubart (DNTH103) in treating generalized Myasthenia Gravis (gMG). Both 300mg and 600mg doses administered every two weeks showed statistically significant improvements in key efficacy measures.
The trial demonstrated rapid and sustained effectiveness starting from Week 1, with significant improvements in MG-ADL and QMG scores through Week 13. The 300mg dose proved equally effective as 600mg, supporting a convenient single-dose administration via subcutaneous autoinjector every two weeks.
Importantly, claseprubart showed a favorable safety profile with no serious infections, autoimmune symptoms, or drug-related serious adverse events. The company plans to initiate a Phase 3 gMG trial in 2026.
Dianthus Therapeutics (NASDAQ:DNTH) ha reso noti i risultati positivi della fase 2 MaGic per claseprubart (DNTH103) nel trattamento della miastenia gravis generalizzata (gMG). Le dose di 300 mg e 600 mg, somministrate ogni due settimane, hanno mostrato miglioramenti statisticamente significativi nei principali parametri di efficacia.
Lo studio ha evidenziato un effetto rapido e duraturo gi脿 dalla prima settimana, con miglioramenti significativi nei punteggi MG-ADL e QMG fino alla settimana 13. La dose da 300 mg si 猫 dimostrata altrettanto efficace rispetto alla 600 mg, supportando una comoda somministrazione con un singolo dosatore autoiniettabile sottocutaneo ogni due settimane.
Di rilievo, claseprubart ha mostrato un profilo di sicurezza favorevole, senza infezioni gravi, sintomi autoimmuni o eventi avversi gravi correlati al farmaco. L'azienda prevede di avviare una fase 3 per gMG nel 2026.
Dianthus Therapeutics (NASDAQ:DNTH) inform贸 resultados positivos de la fase 2 MaGic para claseprubart (DNTH103) en el tratamiento de la miastenia gravis generalizada (gMG). Tanto las dosis de 300 mg como de 600 mg, administradas cada dos semanas, mostraron mejoras estad铆sticamente significativas en medidas clave de eficacia.
El ensayo demostr贸 una eficacia r谩pida y sostenida desde la semana 1, con mejoras significativas en las puntuaciones MG-ADL y QMG hasta la semana 13. La dosis de 300 mg result贸 igual de eficaz que la de 600 mg, respaldando una c贸moda administraci贸n con un autoinyector subcut谩neo de una sola dosis cada dos semanas.
Importante: claseprubart present贸 un perfil de seguridad favorable, sin infecciones graves, s铆ntomas autoinmunes ni eventos adversos graves relacionados con el f谩rmaco. La compa帽铆a planea iniciar una fase 3 de gMG en 2026.
Dianthus Therapeutics (NASDAQ:DNTH)電� 鞚茧皹頇� 欷戩攴茧霠レ(gMG) 旃橂毳� 鞙勴暅 claseprubart (DNTH103)鞚� 2靸� MaGic 鞛勳儊鞐愳劀 旮嶌爼鞝侅澑 瓴瓣臣毳� 氚滍憸頄堨姷雼堧嫟. 300mg 氚� 600mg 鞖╇焿鞚� 2欤茧雼� 韴棳頃� 甑� 氇憪 欤检殧 須姤 歆�響滌棎靹� 韱店硠鞝侅溂搿� 鞙犾潣頃� 臧滌劆鞚� 氤挫榾鞀惦媹雼�.
鞛勋儊鞚赌 1欤检皑攵�韯� 牍犽ゴ瓿� 歆�靻嶌爜鞚� 須臣毳� 鞛呾頄堨溂氅�, 13欤检皑旯岇 MG-ADL 氚� QMG 鞝愳垬鞐愳劀 鞙犾潣頃� 臧滌劆鞚� 頇曥澑霅橃棃鞀惦媹雼�. 300mg 鞖╇焿鞚� 600mg瓿� 霃欕摫頃� 須姤鞚� 氤挫棳 2欤茧雼� 頂柬晿 鞛愲彊欤检瀰旮半ゼ 韱淀暅 雼澕 韴棳搿滊弰 韼鸽Μ頃橁矊 靷毄頃� 靾� 鞛堨潓鞚� 霋冯皼旃暕雼堧嫟.
韸鬼瀳 claseprubart電� 鞎堨爠靹� 頂勲韺岇澕鞚� 鞏戫樃頄堨溂氅�, 欷戩 臧愳椉, 鞛愱皜氅挫棴 歃濎儊 霕愲姅 鞎诫 甏�霠� 欷戨寑頃� 鞚挫儊氚橃潙鞚� 氤搓碃霅橃 鞎婌晿鞀惦媹雼�. 須岇偓電� 2026雲勳棎 gMG 3靸� 鞁滍棙鞚� 鞁滌瀾頃� 瓿勴殟鞛呺媹雼�.
Dianthus Therapeutics (NASDAQ:DNTH) a annonc茅 des r茅sultats positifs de l'essai de phase 2 MaGic portant sur le claseprubart (DNTH103) pour le traitement de la myasth茅nie grave g茅n茅ralis茅e (gMG). Les dosages de 300 mg et 600 mg, administr茅s toutes les deux semaines, ont montr茅 des am茅liorations statistiquement significatives sur les principaux crit猫res d'efficacit茅.
L'茅tude a d茅montr茅 une efficacit茅 rapide et soutenue d猫s la semaine 1, avec des am茅liorations significatives des scores MG-ADL et QMG jusqu'脿 la semaine 13. La dose de 300 mg s'est av茅r茅e aussi efficace que la 600 mg, ce qui soutient une administration pratique par autoinjecteur sous-cutan茅 en dose unique toutes les deux semaines.
Fait notable, le claseprubart a pr茅sent茅 un profil de s茅curit茅 favorable, sans infections graves, sympt么mes auto-immuns ni 茅v茅nements ind茅sirables graves li茅s au m茅dicament. La soci茅t茅 pr茅voit de lancer un essai de phase 3 en gMG en 2026.
Dianthus Therapeutics (NASDAQ:DNTH) meldete positive Ergebnisse der Phase-2-MaGic-Studie zu claseprubart (DNTH103) in der Behandlung der generalisierten Myasthenia gravis (gMG). Sowohl 300 mg- als auch 600 mg-Dosen, verabreicht alle zwei Wochen, zeigten statistisch signifikante Verbesserungen in den wichtigsten Wirksamkeitsparametern.
Die Studie zeigte eine schnelle und anhaltende Wirkung ab Woche 1, mit signifikanten Verbesserungen der MG-ADL- und QMG-Werte bis Woche 13. Die 300 mg-Dosis erwies sich als ebenso wirksam wie die 600 mg-Dosis, was eine komfortable Einzeldosisgabe mittels subkutanem Autoinjektor alle zwei Wochen unterst眉tzt.
Wichtig: claseprubart wies ein g眉nstiges Sicherheitsprofil auf, ohne schwere Infektionen, autoimmune Symptome oder schwerwiegende arzneimittelbezogene Nebenwirkungen. Das Unternehmen plant den Start einer Phase-3-gMG-Studie im Jahr 2026.
- Both 300mg and 600mg doses achieved statistically significant improvements in multiple efficacy measures
- Rapid onset of action with improvements visible from Week 1
- 300mg dose proved as effective as 600mg, enabling convenient lower-dose administration
- Favorable safety profile with no serious adverse events or infections
- Potential for administration without Boxed Warning or REMS requirements
- Phase 3 trial not starting until 2026, indicating lengthy timeline to potential approval
Insights
Dianthus' claseprubart shows compelling Phase 2 efficacy and safety in generalized Myasthenia Gravis, positioning it as a potential best-in-class therapy.
The Phase 2 MaGic trial results for claseprubart represent a significant clinical advancement in the treatment of generalized Myasthenia Gravis (gMG). Both tested doses (300mg and 600mg Q2W) demonstrated statistically significant improvements in the primary efficacy measures 鈥� MG-ADL and QMG scores at Week 13. Particularly impressive is the rapid onset of action, with significant improvements observed as early as Week 1.
The 300mg dose performed comparably to the 600mg dose across key efficacy endpoints, which is clinically meaningful as it supports the development of a lower-dose option with potentially fewer side effects. The data showing improvements in Minimal Symptom Expression (MSE), MGC scores, and quality of life measures (MG-QoL-15r) indicates comprehensive symptom control that addresses multiple aspects of this debilitating autoimmune condition.
From a safety perspective, the absence of serious infections, emergent autoimmune disease, or drug-related serious adverse events is particularly noteworthy for a complement inhibitor. This favorable safety profile suggests claseprubart may avoid the Boxed Warning or REMS requirements for meningococcal infections that have limited other complement-targeting therapies.
The planned convenient administration as a subcutaneous autoinjector dosed every two weeks represents a significant quality-of-life improvement over more frequent or intravenous therapies. With Phase 3 trials anticipated to begin in 2026, including evaluation of an even more convenient quarterly dosing option, claseprubart appears well-positioned to potentially capture significant market share in the gMG treatment landscape if approved.
Claseprubart 300mg and 600mg Q2W doses both achieved statistically significant and clinically meaningful improvements in Myasthenia Gravis Activities of Daily Living (MG-ADL) and Quantitative Myasthenia Gravis (QMG) scores at Week 13
Claseprubart demonstrated a rapid and sustained onset of action, with both doses achieving statistically significant improvements in MG-ADL and QMG scores at Week 1
Claseprubart 300mg Q2W dose was also statistically significant and clinically meaningful across other key efficacy endpoints, including Minimal Symptom Expression (MSE), Myasthenia Gravis Composite (MGC) Score and the Myasthenia Gravis Quality of Life Scale (MG-QoL-15r)
Both 300mg and 600mg doses of claseprubart were comparable across key efficacy endpoints, supporting its target product profile of a single, convenient 300mg/2mL self-administered, subcutaneous autoinjector dosed once every two weeks
Claseprubart had a favorable safety profile with no related serious infections, clinical symptoms of emergent autoimmune disease, or drug-related serious adverse events or discontinuations, supporting its target product profile of no Boxed Warning or REMS for meningococcal infections
Phase 3 gMG trial evaluating 300mg/2mL Q2W and Q4W vs. placebo anticipated to initiate in 2026
Investor conference call and webcast to be held today, September 8, 2025 at 8:00 a.m. ET听
NEW YORK and WALTHAM, Mass., Sept. 08, 2025 (GLOBE NEWSWIRE) -- Dianthus Therapeutics, Inc. (Nasdaq: DNTH), a clinical-stage biotechnology company dedicated to advancing the next generation of antibody complement therapeutics to treat severe autoimmune diseases, today announced positive top-line data from the Phase 2 MaGic trial evaluating the safety and efficacy of claseprubart (DNTH103) in adults with acetylcholine receptor antibody positive (AChR+) generalized Myasthenia Gravis (gMG).
鈥淭he results from MaGic mark a significant milestone for Dianthus and are an important step forward for people living with gMG. These results are also a reflection of the commitment and talent of the entire Dianthus team, and I want to thank them for their outstanding execution of this clinical trial,鈥� said Marino Garcia, President and Chief Executive Officer of Dianthus Therapeutics. 鈥淭he concordance of the efficacy and safety data from the MaGic trial strongly support our best-in-class target product profile for claseprubart 300mg/2mL Q2W in gMG and bolsters our confidence in our execution of the CIDP and MMN clinical programs.鈥�
About the
The MaGic trial is a global, randomized, double-blind, placebo-controlled Phase 2 trial that enrolled 65 AChR+ participants with gMG. Following an initial loading dose, claseprubart was administered every two weeks (Q2W) via subcutaneous (S.C.) injection at a dose of 300mg/2mL or 600mg/4mL. The initial randomized treatment duration was 13 weeks, followed by a 52-week open-label extension. The primary endpoint of the study was safety and tolerability. Secondary and exploratory efficacy endpoints included Myasthenia Gravis Activities of Daily Living Scale听(MG-ADL) and Quantitative Myasthenia Gravis (QMG) score assessments, as well as Minimal Symptom Expression (MSE), Myasthenia Gravis Composite (MGC) score and the Myasthenia Gravis Quality of Life Scale (MG-QOL-15r).听
Summary Results from the
Claseprubart 300mg and 600mg demonstrated rapid, 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 Q2W dose was also statistically significant and clinically meaningful across other key efficacy endpoints, including Minimal Symptom Expression (MSE), Myasthenia Gravis Composite (MGC) Score and the Myasthenia Gravis Quality of Life Scale (MG-QoL-15r).
Claseprubart was generally well tolerated with no drug-related Serious Adverse Events (SAEs) or discontinuations due to any related adverse event. Claseprubart had a favorable clinical safety profile comparable to placebo with no treatment-related serious bacterial infections and no clinical symptoms of emergent autoimmune disorders observed.
鈥淚 would like to thank the MaGic investigators and site staff who made the seamless execution of this study possible,鈥� said Simrat Randhawa, MD, Chief Medical Officer of Dianthus Therapeutics. 鈥淭he consistent and meaningful treatment effect seen in both treatment arms across multiple standard MG efficacy metrics in this Phase 2 trial gives me and my team great confidence in our ability to execute a successful Phase 3 trial.鈥�
鈥済MG is a chronic condition that can be treated with complement and FcRn inhibitors. The ideal drug should provide continuous symptom control and have low infection risks, infrequent side effects, convenient dosing schedule, and minimal administration burden,鈥� said Dr. Tuan Vu, a Professor of Neurology at the University of South Florida Morsani College of Medicine. 鈥淚f these impressive results were replicated in a Phase 3 trial, claseprubart may be a differentiated treatment option for patients with gMG.鈥�
Efficacy Results
MG-ADL
- Claseprubart dosed at 300mg S.C. Q2W achieved a statistically significant and clinically meaningful mean improvement from baseline of 4.6 points in MG-ADL score at Week 13 (placebo-adjusted improvement: 1.8 points; P=0.0113). A statistically significant improvement in the MG-ADL was also seen as early as Week 1 with 300mg.
- Claseprubart dosed at 600mg S.C. Q2W achieved a statistically significant and clinically meaningful mean improvement from baseline of 5.4 points in MG-ADL score at Week 13 (placebo-adjusted improvement: 2.6 points; P=0.0006). A statistically significant improvement in the MG-ADL was also seen as early as Week 1 with 600mg.
- As expected, there was no statistically significant difference between the claseprubart 300mg and 600mg arms in MG-ADL score at any time point.
QMG
- Claseprubart dosed at 300mg S.C. Q2W achieved a statistically significant and clinically meaningful mean improvement from baseline of 4.4 points in QMG score at Week 13 (placebo-adjusted improvement: 2.4; P=0.0144). A statistically significant improvement in QMG was also seen as early as Week 1 with 300mg.
- Claseprubart dosed at 600mg S.C. Q2W achieved a statistically significant and clinically meaningful mean improvement from baseline of 4.5 points in QMG score at Week 13 (placebo-adjusted improvement: 2.5; P=0.0111). A statistically significant improvement in QMG was also seen as early as Week 1 with 600mg.
- As expected, there was no statistically significant difference between the claseprubart 300mg and 600mg arms in QMG score at any time point.
Efficacy Summary at Week 13
| 听 | Placebo N=22 | Claseprubart 300mg Q2W N=21 | Claseprubart 600mg Q2W N=22 | |||||
| 听 | 听 | Absolute | Placebo-Adjusted | Absolute | Placebo-Adjusted | |||
| MG-ADL mean change from baseline | -2.8 | 听 | -4.6 | 听 | -1.8 (P=0.0113)* | -5.4 | 听 | -2.6 (P=0.0006)* |
| QMG mean change from baseline | -2.0 | 听 | -4.4 | 听 | -2.4 (P=0.0144)* | -4.5 | 听 | -2.5 (P=0.0111)* |
| MSE | 听 | 听 | (P=0.0550)* | 听 | (P=0.1031) | |||
| MGC mean change from baseline | -3.1 | 听 | -8.7 | 听 | -5.6 (P=0.0008)* | -8.6 | 听 | -5.5 (P=0.0008)* |
| MG-QoL-15r mean change from baseline | -3.9 | 听 | -6.1 | 听 | -2.2 (P=0.0414)* | -5.4 | 听 | -1.5 (P=0.1122) |
*One-sided p-values are presented for comparisons of claseprubart vs placebo, with any p-value below 0.1 considered nominally statistically significant.
Safety and Tolerability Results
- Claseprubart was generally well tolerated and demonstrated a clinical safety profile in both treatment arms comparable to placebo.
- No infection signal was observed, including no related serious bacterial infections in the treatment arms;听the only related serious adverse event (SAE) of infection occurred in the placebo arm.
- There were no symptoms indicative of autoimmune activation.
- Injection site reactions (ISRs) were infrequent and generally mild, and there were no claseprubart discontinuations from RCT due to related AEs.
Next Steps
鈥淏ased on the comparable efficacy data demonstrated in MaGic by the 300mg and 600mg Q2W doses, as well as encouraging early data from the open-label extension,听we are planning for an end-of-Phase 2 meeting with the FDA to align on the proposed design of听a听Phase 3 trial for claseprubart in Myasthenia Gravis that investigates听both 300mg Q2W and 300mg Q4W doses vs. placebo,鈥� said Marino Garcia, President and Chief Executive Officer of Dianthus Therapeutics. 鈥�2026 will be a catalyst-rich year, with the initiation of the Phase 3 gMG trial followed by results from the interim responder analysis of the Phase 3 CAPTIVATE trial in Chronic Inflammatory Demyelinating Polyneuropathy (CIDP) and top-line results from the Phase 2 MoMeNtum trial in Multifocal Motor Neuropathy (MMN), both in 2H鈥�26.鈥�
Investor Conference Call & Webcast to be Held at 8:00 a.m. ET Today
Dianthus Therapeutics will host an investor call and webcast to discuss the Phase 2 MaGic results today, September 8, 2025 at 8:00 a.m. ET. Please click to register for this event.
The live webcast may be accessed via the Investors section of the Dianthus Therapeutics website at . A replay of the webcast will be available following the call.
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-class pipeline-in-a-product across a range of autoimmune disorders with high unmet need. Dianthus is building a neuromuscular franchise with claseprubart and expects to initiate a Phase 3 trial in gMG in 2026, the interim responder analysis of the Phase 3 CAPTIVATE trial in Chronic Inflammatory Demyelinating Polyneuropathy in 2H鈥�26, and top-line data from the Phase 2 MoMeNtum trial in Multifocal Motor Neuropathy in 2H鈥�26.
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
About Dianthus Therapeutics
Dianthus Therapeutics is a clinical-stage biotechnology company dedicated to designing and delivering novel, best-in-class monoclonal antibodies with improved selectivity and potency. Based in New York City and Waltham, Mass., Dianthus is comprised of an experienced team of biotech and pharma executives who are leading the development of next-generation antibody complement therapeutics, aiming to deliver transformative medicines for people living with severe autoimmune and inflammatory diseases.
To learn more, please visit and follow us on .听
Cautionary Statement Regarding Forward-Looking Statements
Certain statements in this press release, other than purely historical information, may constitute 鈥渇orward-looking statements鈥� within the meaning of the federal securities laws, including for purposes of the safe harbor provisions under the United States Private Securities Litigation Reform Act of 1995, express or implied statements regarding future plans and prospects, including statements regarding the expectations or plans for discovery, preclinical studies, clinical trials and research and development programs, in particular with respect to claseprubart, and any developments or results in connection therewith, including the target product profile and administration of claseprubart; the anticipated timing of the initiation and results from those studies and trials; expectations regarding the clinical trial design for the Phase 3 trial for claseprubart in gMG; expectations regarding the time period over which the Company鈥檚 capital resources are expected to be sufficient to fund its anticipated operations; and expectations regarding market size, patient population size, and potential opportunities for complement therapies, in particular with respect to claseprubart. Claseprubart is an investigational agent that is not approved as a therapy in any indication in any jurisdiction worldwide. The words 鈥渙pportunity,鈥� 鈥減otential,鈥� 鈥渕ilestones,鈥� 鈥渞unway,鈥� 鈥渨ill,鈥� 鈥渁nticipate,鈥� 鈥渁chieve,鈥� 鈥渘ear-term,鈥� 鈥渃atalysts,鈥� 鈥減ursue,鈥� 鈥減ipeline,鈥� 鈥渂elieve,鈥� 鈥渃ontinue,鈥� 鈥渃ould,鈥� 鈥渆stimate,鈥� 鈥渆xpect,鈥� 鈥渋ntend,鈥� 鈥渕ay,鈥� 鈥渕ight,鈥� 鈥減lan,鈥� 鈥減ossible,鈥� 鈥減redict,鈥� 鈥減roject,鈥� 鈥渟hould,鈥� 鈥渟trive,鈥� 鈥渨ould,鈥� 鈥渁im,鈥� 鈥渢arget,鈥� 鈥渃ommit,鈥� and similar expressions (including the negatives of these terms or variations of them) generally identify forward-looking statements, but the absence of these words does not mean that statement is not forward looking.
Actual results could differ materially from those included in the forward-looking statements due to various factors, risks and uncertainties, including, but not limited to, that preclinical testing of claseprubart and data from clinical trials may not be predictive of the results or success of ongoing or later clinical trials, that the development of claseprubart or the Company's other compounds may take longer and/or cost more than planned, that the Company may be unable to successfully complete the clinical development of the Company鈥檚 compounds, that the Company may be delayed in initiating, enrolling or completing its planned clinical trials, and that the Company's compounds may not receive regulatory approval or become commercially successful products. These and other risks and uncertainties are identified under the heading "Risk Factors" included in the Company鈥檚 Annual Report on Form 10-K for the period ended December 31, 2024, and other filings that the Company has made and may make with the SEC in the future. Nothing in this press release should be regarded as a representation by any person that the forward-looking statements set forth herein will be achieved or that any of the contemplated results of such forward-looking statements will be achieved.
The forward-looking statements in this press release speak only as of the date they are made and are qualified in their entirety by reference to the cautionary statements herein. Dianthus undertakes no obligation to publicly update or revise any forward-looking statement, whether as a result of new information, future events or otherwise, except as required by law.
Contact
Jennifer Davis Ruff
Dianthus Therapeutics
FAQ
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