AbClon announced on the 26th that HLX22 shall be an innovative new drug with higher efficacy than existing standard treatments and also being developed as a treatment for breast cancer with high HER2 expression.

According to Henlius's business report published recently, HLX22 belongs to a key pipeline that shows higher efficacy than existing standard treatments. It is an antibody therapy based on AC101, which AbClon licensed out in 2016, and AbClon is eligible to receive milestones upon clinical trial stages and royalties upon commercialization.

HLX22 is an antibody that targets a specific part of the HER2 protein on cancer cells. Unlike existing antibody treatments, it affects cancer cells more appropriately and efficiently by differentiating the antigen-binding site of HER2. When it binds to HER2 along with trastuzumab (HLX02), it has shown to more effectively remove HER2 protein from the cancer cell surface, inhibiting cancer cell growth signals.

The combination therapy of HLX22 and trastuzumab showed superior efficacy in gastric cancer treatment compared to the existing combination therapy of trastuzumab and pertuzumab, and showed therapeutic effects regardless of PD-L1 expression levels. In particular, severe diarrhea, which is reported as a frequent adverse event in existing first-line HER2-positive gastric cancer treatments, was not observed with HLX22, indicating positive evaluations in terms of safety.

Currently, the standard therapy for metastatic gastric cancer and gastroesophageal junction cancer is the combination therapy of trastuzumab and anticancer chemotherapy, approved in 2010. This therapy showed a progression-free survival of 6.7 months, an overall survival of 13.8 months, and a response duration of 6.9 months. In contrast, the HLX22 combination therapy demonstrated outstanding clinical efficacy, with unreached progression-free survival, overall survival, and response duration as of the 20.3-month median follow-up period.

Meanwhile, HLX22 is also being developed as a treatment for breast cancer with high HER2 expression rates, which is expected to further expand its application range. HER2-positive breast cancer accounts for approximately 15-20% of all breast cancers, with 2.3 million new cases occurred annually, and be a key market for HER2-targeted therapies along with gastric cancer. Based on such diverse treatment potential, HLX22 is expected to become a new standard in solid tumor treatment.

An AbClon official said, "Following the outstanding efficacy of HLX22 in gastric cancer treatment, HLX22 is showing potential for application in other solid tumor treatments such as breast cancer, and expected to play a crucial role in targeting HER2-positive cancers. We expect HLX22 to provide an important treatment option in more cancer treatment markets in the future."

They further emphasized, "HLX22 is innovative approach, which precisely blocks cancer cell growth signals, and has a high potential to change the paradigm of cancer treatment in the future. It can bring hope to cancer patients who do not respond to existing treatments."