▎WuXi AppTec Content Team Report

Screenshot source: CDE official website

IgG4-RD is a chronic, systemic, immune-mediated fibroinflammatory disease that can affect multiple organs in the body.B cells play a central role in the pathogenesis of IgG4-RD.In IgG4-RD, B cells expressing CD19 (CD19+)Considered to drive inflammation and fibrosis processes, and interact with other immune cells involved in disease activity.

Inebilizumab is a CD19 B-cell depleting antibody.In 2019, Hansoh Pharma entered into a licensing agreement with Viela Bio to obtain the exclusive rights to develop and commercialize the product in mainland China, Hong Kong, and Macao (Viela Bio was acquired by Horizon Therapeutics in 2021, which was subsequently acquired by Amgen in 2023). Inebilizumab has previously been approved for marketing in the United States and China for the treatment ofAdult patients with neuromyelitis optica spectrum disorder (NMOSD) who are positive for aquaporin-4 (AQP4) antibodies。

In February this year, Hansoh Pharma announced that the injection of Inebilizumab for IgG4-RD new indications was officially included in the priority review by CDE. This is based on itsGlobal Pivotal Phase 3 Trial MITIGATEThe positive results were published in The New England Journal of Medicine in November 2024.NEJM). In August 2024, the FDA granted inebilizumab breakthrough therapy designation for IgG4-related disease based on the MITIGATE study data, and relevant regulatory procedures are currently being submitted.

The MITIGATE study was conducted at 80 clinical trial research centers across 22 countries, including China.Key findings of the study include:

• During the 52-week placebo-controlled period, compared with placebo,Subjects treated with inebilizumab had a significantly reduced risk of IgG4-RD relapse by 87%., which was clinically and statistically significant; 7 out of 68 subjects treated with inebilizumab experienced relapses, compared to 40 out of 67 subjects treated with placebo.

• During the placebo-controlled period, the annualized relapse rate was reduced in patients receiving treatment as determined by the adjudication committee;Subjects receiving inebilizumab had a rate of 0.10, while those receiving placebo had a rate of 0.71.

• 57.4% (39/68) of subjects treated with inebilizumab achieved complete remission without relapse and without the need for further treatment at Week 52., while the placebo group was 22.4% (15/67).

• 58.8% (40/68) of subjects treated with inebilizumab achieved complete remission without relapse and without the need for corticosteroids at week 52., while the placebo group was 22.4% (15/67).

• The studyThe unique mechanism of action of inebilizumab has been validated.Capable of rapidly and continuously depleting the number of peripheral B cells, thereby reducing the levels of disease biomarkers.。

Study data also showed that 89.7% (61/68) of subjects treated with inebilizumab did not require the use of glucocorticoids to control the disease during the placebo-controlled period, compared to 37.3% (25/67) in the placebo group.After Week 8, the total glucocorticoid dosage in the inebilizumab treatment group was 10 times less than that in the placebo group.The safety results of the placebo-controlled period were consistent with the known safety profile of inebilizumab.

References:

[1] Official website of the Center for Drug Evaluation, National Medical Products Administration of China. Retrieved Mar 4, 2025, from https://www.cde.org.cn/main/xxgk/listpage/4b5255eb0a84820cef4ca3e8b6bbe20c

[2] Hansoh Pharma's Xinyue® (Inebilizumab) New Indication Granted Priority Review for the Treatment of IgG4-Related Disease. Retrieved Feb 10， 2025, from https://mp.weixin.qq.com/s/nV6NjgUzmvWhDk-pYqXE_g