Zai Lab's Efgartigimod Alfa Injection for CIDP Receives Priority Review in China

Zai Lab Limited has announced the acceptance of a supplemental Biologics License Application (sBLA) by the Center for Drug Evaluation (CDE) of the China National Medical Products Administration (NMPA) for efgartigimod alfa injection (subcutaneous injection) aimed at treating chronic inflammatory demyelinating polyneuropathy (CIDP). This acceptance, which includes a priority review designation granted on May 11, 2024, and a Breakthrough Therapy Designation on September 18, 2023, marks a significant milestone for the company's efforts in addressing serious autoimmune diseases in China.

Dr. Harald Reinhart, President and Head of Global Development, Neuroscience, Autoimmune & Infectious Diseases at Zai Lab, emphasized the importance of this step in providing a new treatment option for CIDP patients in China. With approximately 50,000 diagnosed individuals in the country, CIDP is a serious condition with limited treatment success using current standards like corticosteroids and intravenous immunoglobulin (IVIg). Dr. Reinhart highlighted the collaborative efforts with argenx in developing a robust pipeline that could improve care for many patients suffering from autoimmune diseases, including CIDP.

The sBLA submission is supported by data from the ADHERE trial, a multicenter, randomized, double-blind, placebo-controlled study evaluating the efficacy of efgartigimod SC in treating CIDP. Zai Lab's participation in the trial included enrolling patients from Greater China, with the treatment responses of these participants aligning with global study outcomes. A subgroup analysis indicated a 69% reduction in relapse rates among Chinese participants treated with efgartigimod SC compared to placebo. Furthermore, 78% of these participants showed clinical improvement in the study's open-label portion, reinforcing the role of IgG autoantibodies in CIDP's underlying biology. The weekly dosing of efgartigimod SC, extending up to a year, demonstrated favorable safety and tolerability in the Chinese cohort, consistent with global trial results.

In addition to the CIDP application, Zai Lab has recently introduced VYVGART® (efgartigimod alfa injection) for generalized myasthenia gravis (gMG) in mainland China, making it the first and only approved FcRn antagonist for gMG patients. In July 2023, the CDE also accepted the Biologics License Application (BLA) for efgartigimod SC for gMG in China.

CIDP, a condition affecting around 50,000 individuals in mainland China, is typically managed with corticosteroids and intravenous immunoglobulin (IVIg), with plasma exchange (PLEX) being an option for refractory cases. However, access to PLEX or IVIg remains limited in many parts of the world, including China. Given the chronic nature of CIDP and the need for long-term treatment, there is a substantial demand for alternative therapies that are effective, well-tolerated, and convenient.

The ADHERE trial, sponsored by argenx, enrolled 322 adult patients with CIDP who were either treatment-naïve or had been on immunoglobulin therapy or corticosteroids. Participants underwent a rigorous process to confirm CIDP diagnosis and demonstrate active disease before entering the double-blind, placebo-controlled phase of the trial. The primary endpoint was the hazard ratio for the time to first adjusted INCAT deterioration (relapse).

VYVGART Hytrulo, a subcutaneous combination of efgartigimod alfa and recombinant human hyaluronidase PH20 (rHuPH20), is the first-and-only approved FcRn blocker administered via subcutaneous injection. This product, which facilitates the delivery of biologics, reduces circulating IgG levels by binding to the neonatal Fc receptor (FcRn).

Zai Lab, through an exclusive license agreement with argenx, develops and commercializes efgartigimod in Greater China for various autoimmune indications with significant unmet patient needs. This collaboration underscores Zai Lab's commitment to bringing innovative treatments to patients in China and beyond.