Results from a pivotal Phase 3 clinical trial evaluating Telitacicept in patients with generalized myasthenia gravis (gMG) were presented at the American Academy of Neurology Annual Meeting in San Diego on April 8, 2025, revealing exceptional efficacy data that could position the drug as a leading treatment option for this debilitating autoimmune condition.
The trial (NCT05737160), conducted in China and led by Professor Jian Yin of Beijing Hospital, demonstrated that 98.1% of patients receiving Telitacicept 240 mg achieved a clinically meaningful reduction of ≥3 points in the Myasthenia Gravis Activities of Daily Living (MG-ADL) score at 24 weeks, compared to just 12.0% in the placebo group.
Unprecedented Efficacy in Key Clinical Measures
Telitacicept, a novel fusion protein independently designed and developed by RemeGen Co., Ltd., uniquely targets both B-lymphocyte stimulator (BLyS) and a proliferation-inducing ligand (APRIL). This dual-targeting mechanism appears to provide comprehensive inhibition of abnormal B cells and plasma cells, effectively reducing pathogenic antibodies that drive myasthenia gravis.
The multicenter, randomized, double-blind, placebo-controlled study enrolled 114 gMG patients with baseline MG-ADL scores ≥6 and QMG scores ≥8. Participants were equally divided between the Telitacicept 240 mg and placebo groups.
Key efficacy findings at Week 24 included:
- Mean change in MG-ADL score: -5.74 for Telitacicept vs. -0.91 for placebo
- Patients achieving ≥3-point reduction in MG-ADL: 98.1% for Telitacicept vs. 12.0% for placebo
- Mean change in Quantitative Myasthenia Gravis (QMG) score: -8.66 for Telitacicept vs. -2.27 for placebo
- Patients achieving ≥5-point reduction in QMG: 87.0% for Telitacicept vs. 16.0% for placebo
Notably, improvements in both MG-ADL and QMG scores were observed as early as 4 weeks after treatment initiation and continued to improve throughout the 24-week treatment period, suggesting potential for long-term disease modification.
Favorable Safety Profile
Telitacicept demonstrated a reassuring safety profile, with overall adverse event (AE) incidence comparable to placebo. Interestingly, infection-related AEs were actually lower in the Telitacicept group compared to placebo (45.6% vs. 59.6%), a finding that contrasts with some immunosuppressive therapies.
Professor Jian Yin, the principal investigator, emphasized the clinical significance of these results: "Telitacicept demonstrated rapid and significant clinical improvement in the phase 3 trial, and was well tolerated. Its dual-targeting mechanism not only inhibits abnormal B cells and plasma cells thoroughly and reduces the level of pathogenic antibodies, but also effectively slows down disease progression in the long term, and reduces steroid dosage as symptoms improve, providing a more precise, efficient, persistent, and safer option for gMG treatment."
Addressing a Significant Unmet Need
Generalized myasthenia gravis represents a substantial global health burden, affecting approximately 1.2 million patients worldwide, including about 220,000 in China. The autoimmune disease causes neuromuscular junction transmission disorders, leading to muscle weakness, fatigue, and potentially life-threatening complications.
Current treatment options often provide inadequate symptom control or carry significant side effects, creating a substantial unmet medical need. More than 85% of myasthenia gravis patients progress to the generalized form within 24 months of disease onset.
Dr. Jianmin Fang, CEO of RemeGen, highlighted the significance of these findings: "The phase 3 data of Telitacicept for MG is clinically meaningful. There is a large unmet medical need in MG because the disease presents significant threat to patients' health and life-span. This breakthrough means that we have a new, effective treatment for MG as Telitacicept can significantly improve patients' symptoms and bring long term benefits to MG patients."
Regulatory and Global Development Strategy
The Biologics License Application (BLA) for Telitacicept in gMG has already been accepted by China's Center for Drug Evaluation (CDE), with approval anticipated in the second quarter of 2025.
Simultaneously, RemeGen is advancing a global multicenter Phase 3 trial of Telitacicept for gMG, with enrollment expected to complete by late 2025 or early 2026. The company has prioritized this indication by sidelining two other global Phase 3 trials with the molecule, underscoring the strategic importance of this therapeutic area.
If approved, Telitacicept would represent a significant advancement in neuroimmunology and potentially establish a new standard of care for patients with generalized myasthenia gravis worldwide.
