On August 13, 2024, RemeGen Co., Ltd (“RemeGen”) (688331.SH/09995.HK) announced that a Phase III clinical trial on its innovative drug Telitacicept (RC18, trade name: Tai'ai®) in treatment of generalized myasthenia gravis (gMG) had achieved its primary endpoint and the company is planning to file BLA submission to the Center for Drug Evaluation (CDE) of China’s National Medical Products Administration (NMPA). Telitacicept is a BLyS/APRIL dual-target fusion protein independently developed by RemeGen.

The Phase III clinical trial was a multicenter, randomized, double-blind, placebo-controlled study designed to evaluate the efficacy and safety of Telitacicept in treatment of gMG. It was conducted in China with a Beijing hospital as the leading site. Eligible patients were randomized to the Telitacicept 240 mg group or the placebo group in a 1:1 ratio. The results demonstrated that Telitacicept had favorable efficacy and safety profiles, evidenced by the continuous reduction of clinical symptoms among gMG patients in the treatment group.

Myasthenia gravis (MG) is a rare, chronic autoimmune disorder caused by autoantibodies against acetylcholine receptors (AChR) on the postsynaptic membrane, muscle-specific kinase, or other AChR-related proteins. This condition can lead to varying degrees of impairment in eye movement, swallowing, speech, physical activity, and respiration. Approximately 85% of individuals with MG progress to gMG wherein weakness spreads from extraocular muscles to other muscle groups. Aware of its impact, China includes MG in its First Batch of Rare Disease Catalog. According to a report by Frost & Sullivan, as of 2025, approximately 1.146 million individuals worldwide are predicted to be affected by MG, with 216,700 in China.

Currently, there is no definitive treatment available for MG. However, targeted biological therapies have emerged as an area of special interest by virtue of their effectiveness, precision and safety. Among these, B cell targeted therapies stand out for their promising therapeutic potential. Researches 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.

Recently, inspiring news keeps pouring in for Telitacicept in treatment of MG. On August 5, 2024, RemeGen announced that it had achieved the milestone of First Patient In in the US for its global multi-center Phase III clinical trial on MG.  Notably, Telitacicept has received breakthrough therapy designation from China’s NMPA, as well as orphan drug designation and fast track designation from the US FDA.