On August 5, 2024, RemeGen Co., Ltd. (“RemeGen”) (688331.SH/09995.HK) announced that it had successfully achieved the milestone of First Patient In (FPI) in US for its global multicenter Phase III clinical trial on its innovative drug Telitacicept (RC18, trade name: Tai'ai®) for the treatment of generalized myasthenia gravis (gMG). Telitacicept is a BLyS/APRIL dual-target fusion protein independently developed by RemeGen.

This milestone marks an important step forward in this global clinical trial on Telitacicept and will bring new hope to patients with myasthenia gravis (MG) worldwide. Telitacicept has been granted orphan drug and fast track designations by the U.S. Food and Drug Administration (FDA) and breakthrough therapy designation by the National Medical Products Administration (NMPA) of China for its indication of MG. Results of a Phase III clinical trial on MG will be read out soon.

This global multicenter Phase III clinical trial is a randomized, double-blind, placebo-controlled study designed to evaluate the efficacy and safety of Telitacicept in treating patients with generalized myasthenia gravis (gMG). It is planned to enroll 180 patients from different countries and regions worldwide.

MG is a rare, chronic autoimmune disorder characterized by defective transmission at the neuromuscular junction. It can lead to varying degrees of impairment in eye movement, swallowing, speech, physical activity, and respiration. According to a report by Frost & Sullivan, as of 2025, approximately 1.146 million individuals worldwide are predicted to be affected by MG, with 69,500 in the US and 216,700 in China.

Treatment options available now for MG include cholinesterase inhibitors, glucocorticoids, and immunosuppressants. The lack of effective and precise targeted therapies, together with other factors such as poor efficacy, drug tolerance, or contraindications of the prevailing regimens, makes it hard for a proportion of patients to effectively control their conditions, leaving a huge unmet clinical need.

In recent years, B-cell targeted therapies have emerged as a promising treatment option with significant therapeutic potential in MG. Studies have shown that these therapies can significantly lower the relapse rate and the drug discontinuation rate among MG patients, compared to conventional immunotherapy regimens. As a novel dual-target fusion protein directed at B cells, Telitacicept simultaneously targets B-lymphocyte stimulator (BLyS) and a proliferation-inducing ligand (APRIL). This mechanism can effectively inhibit the excessive activation of B cells and plasma cells, thereby reducing the production of pathogenic antibodies associated with MG and offering significant therapeutic benefits. A clinical trial conducted in China showed that Telitacicept could continuously and effectively reduce clinical symptoms of patients with gMG.

In March 2021, Telitacicept was granted its first approval by NMPA of China. Since then, this innovative agent has benefited over 40,000 patients, demonstrating a favorable efficacy and safety profile. To date, two indications, namely systemic lupus erythematosus and rheumatoid arthritis, have been approved in China, and RemeGen is poised to submit biologics license applications to NMPA for additional indications including myasthenia gravis, Sjogren's syndrome, IgA nephritis, and neuromyelitis optica starting this year.