This is a randomised, double-blind, single-dose, parallel-controlled, four-arm phase 1 study aimed to compare the pharmacokinetics, safety and immunogenicity of HLX11 with US-, EU- and CN-sourced reference pertuzumab administrated intravenously in healthy Chinese male subjects. The primary objective of this study is to compare the pharmacokinetic profiles between HLX11 and the reference drugs sourced from three different regions head-to-head. The secondary objectives are to evaluate the safety, tolerability and immunogenicity of HLX11 and the reference drug and further describe their pharmacokinetic profiles.

HLX11 is a pertuzumab biosimilar developed by Henlius independently in line with Technical Guidelines for the Development and Evaluation of Biosimilars (Tentative), which can be potentially used in combination with trastuzumab and chemotherapy as neoadjuvant or adjuvant treatment for HER2 positive early breast cancer and in combination with trastuzumab and docetaxel in patients with HER2 positive metastatic or unresectable locally recurrent breast cancer patients. HLX11 can specifically bind with the subdomain II of HER2 extracellular domain and inhibit the heterodimerisation of HER2 and other HER family receptors, i.e. EGFR, HER3, and HER4. This will inhibit signal transduction of relevant pathways and lead to the stop of growth and apoptosis of tumour cells. In the meantime, HLX11 can also enhance the tumour-killing activity of immune cells via antibody-dependent cell cytotoxicity.

With the accumulated results and experience from extensive anti-HER2 research, Henlius has a well-established product pipeline in anti-HER2 treatment and built a solid foundation for discovering and developing anti-HER2 bispecific/multi-target antibodies and antibody-drug conjugates (ADC). Up to now, the company’s independently developed and manufactured trastuzumab biosimilar汉曲优® (Zercepac® in the EU) was approved in the EU and China, providing a new standard treatment option for Chinese and European HER2 positive breast and gastric cancer patients. Besides, HLX22，an anti-human epidermal growth factor receptor-2 (HER2) humanized monoclonal antibody injection in phase 2 clinical trial, also has the potential to further improve treatment outcomes for HER2 positive breast cancer and gastric cancer patients. In the future, HLX11 can also be combined with 汉曲优® or HLX22, which will strengthen Henlius’ strategy of Combo. The company will continue innovating and strive for breakthroughs to bring more affordable and quality biologics to patients around the globe.