Harbour BioMed (the "Company"; HKEX: 02142), a global biopharmaceutical company committed to the discovery, development, and commercialization of novel antibody therapeutics focusing on oncology and immunology, announces the positive topline results of its phase III clinical trial of batoclimab (HBM9161) for the treatment of generalized myasthenia gravis (gMG), which is also the first positive pivotal trial outcome for batoclimab worldwide. This marks a major milestone for Harbour BioMed as it is the Company's first product to complete phase III clinical trial and be poised for commercialization to benefit the gMG patients.

This pivotal clinical study aimed to confirm the efficacy and safety of batoclimab in patients with gMG in China. Data received from the phase III trial met primary endpoint as well as key secondary endpoints. Meanwhile, batoclimab treatment was overall safe and well-tolerated, no new safety signal was identified.

"Anti-FcRn treatment has received much attention in patients with gMG, and batoclimab is the first anti-FcRn treatment confirmed efficacious and safe in Chinese gMG population. Following the positive results of the phase II clinical study, the phase III clinical study of batoclimab by Harbour BioMed, through the joint efforts of the sponsor, investigators and patients, overcame all difficulties during the pandemic and completed enrollment of 132 subjects in 10 months, with the last subject out visit on January 14, 2023", said the principal investigator Chongbo Zhao, MD, Professor of Neurology at Huashan Hospital of Fudan University in Shanghai. "The pivotal clinical success sets a monumental milestone for the development of new drugs and further reinforces the position of FcRn antagonists in the treatment of MG through high-level evidence-based medicine. It also demonstrates the strong ability of Chinese clinical investigators to independently organize high-quality clinical studies of innovative therapeutics in rare diseases."

"This breakthrough therapy represents a significant advance in the treatment of multiple pathogenic-IgG mediated autoimmune diseases, where there remains a significant unmet medical need such as gMG indication," said Dr. Jingsong Wang, Founder, Chairman and CEO of Harbour BioMed. "Despite the challenges posed by the COVID-19 pandemic, our commitment to developing life-changing therapies remained steadfast. The successful completion of this clinical trial is a testament to the clinical development capabilities and innovative dedication of our entire team, demonstrating the Company's exceptional ever-increasing business potential as well. We are excited to bring this much-needed therapy to patients, and we look forward to continuing to advance our pipeline of next-generation therapeutics to improve the lives of patients worldwide."

Batoclimab received the "Breakthrough Therapy Certificate" from NMPA in early 2021, and subsequently received positive outcome of the proof-of-concept study for the treatment of Chinese gMG patients completed in August 2021. In October 2022, the Company entered into an agreement with NBP Pharma, a wholly owned subsidiary of the CSPC Group, to co-develop batoclimab in Great China. The Company was responsible for developing and operating the full clinical trial of batoclimab for gMG in China, and will receive tiered royalties based on annual net sales of batoclimab in Greater China according to the agreement.