Efficacy and Safety Evaluation of Telitacicept in Generalized Myasthenia Gravis: A Phase 3 Randomized, Double-Blind, Placebo-Controlled Study

The primary objective of this study is to evaluate the **efficacy** of telitacicept compared to placebo in patients with **generalized myasthenia gravis** (gMG). This is clinically relevant as it aims to determine the therapeutic potential of telitacicept in managing symptoms and improving the quality of life for individuals affected by this chronic autoimmune neuromuscular disorder.

Secondary objectives include:

• Further evaluation of the efficacy of telitacicept versus placebo in patients with gMG.
• Assessment of the safety and tolerability of telitacicept in patients with gMG.
• Evaluation of the immunogenicity of telitacicept in patients with gMG.

The clinical trial involves a total of **108 participants** diagnosed with **Generalized Myasthenia Gravis** (gMG). The study population includes both male and female subjects aged 18 years and older. Participants were selected based on a confirmed diagnosis of gMG, characterized by generalized muscle weakness and meeting the clinical criteria as defined by the Myasthenia Gravis Foundation of America (MGFA) clinical classification II-IV. The trial includes individuals with positive antibodies against AChR or MuSK and specific scores on the MG-ADL and QMG scales. The population is not restricted by gender, and both male and female subjects are included. The trial also considers vulnerable populations. Participants may be on up to two concomitant medications, provided they meet stability criteria prior to baseline. Lifestyle factors such as diet and physical activity are not specified as part of the selection criteria. Key inclusion criteria include the requirement for participants to provide informed consent and agree to use highly effective contraception during the study.

The clinical trial is a **Phase 3**, randomized, double-blind, placebo-controlled study designed to evaluate the efficacy and safety of **telitacicept** in patients with **generalized myasthenia gravis**. The trial includes an open-label extension period and aims to compare the effects of telitacicept against a placebo. The study is expected to commence recruitment on November 30, 2024, and conclude by May 14, 2027, with a maximum treatment period of 72 weeks for participants.

Participants will undergo a series of study visits, beginning with an inclusion (screening) visit to confirm eligibility based on criteria such as age, diagnosis, and antibody status. Following successful screening, participants will be randomized to receive either telitacicept or placebo, administered as a solution for injection in pre-filled syringes. The primary endpoint is the change from baseline in the Myasthenia Gravis Activities of Daily Living (MG-ADL) score at Week 24. Secondary endpoints include changes in the MG Quality of Life scale (MG-QOL15r) and Quantitative Myasthenia Gravis (QMG) score, as well as the proportion of patients achieving minimal symptomatic expression.

Study visits will occur at regular intervals to monitor efficacy and safety, with assessments conducted at baseline, Week 24, and additional follow-up visits as required. The end-of-study visit will mark the conclusion of the participant's involvement, unless early termination is warranted due to adverse events, non-compliance, or withdrawal of consent. Participants are expected to adhere to the study protocol, including the use of highly effective contraception if applicable, and may be withdrawn from the study if they fail to meet these requirements.

The clinical trial involves the administration of **Telitacicept**, an experimental medication, to evaluate its efficacy and safety in patients with generalized myasthenia gravis. Telitacicept is provided as a **solution for injection in a pre-filled syringe**. The active substance, telitacicept, is a protein of other origin, developed by REMEGEN CO. LTD. The pharmaceutical form is specifically designed for injection, although the exact route of administration is categorized as "other use." The dosing schedule and frequency of administration are not explicitly detailed in the provided data, but the maximum treatment period is specified as 72 weeks. The trial does not specify a maximum daily or total dose amount, indicating that dosing may be adjusted based on individual patient needs or study protocol.

The study also includes a **placebo** control, which is visually indistinguishable from the Telitacicept injection. The placebo contains only excipients and no active substances. It serves as a comparator treatment to assess the efficacy of Telitacicept in a double-blind manner. The placebo is administered in the same manner as the experimental medication to ensure blinding is maintained throughout the study. Participant compliance with the dosing schedule will be monitored, although specific methods for compliance monitoring are not detailed in the provided information.

The efficacy of Telitacicept in patients with **generalized myasthenia gravis** will be assessed through a Phase 3, randomized, double-blind, placebo-controlled study with an open-label extension period. The primary endpoint for evaluating efficacy is the change from baseline in the Myasthenia Gravis Activities of Daily Living (MG-ADL) score at Week 24. Secondary endpoints include the change from baseline in the MG Quality of Life scale (MG-QOL15r) at Week 24, the proportion of patients with a decrease of ≥2 points from baseline in the MG-ADL score at Week 24, the proportion of patients with a decrease of ≥3 points from baseline in the Quantitative Myasthenia Gravis (QMG) score at Week 24, the proportion of patients who achieved minimal symptomatic expression (MSE, defined as having an MG-ADL score of 0 or 1) at Week 24, and the change from baseline in the QMG score at Week 24.