Researchers Report on Clinical Program for Proposed Trastuzumab Biosimilar, HLX02

During the European Society for Medical Oncology’s Asia 2018 annual meeting, held in Singapore from November 23 to November 25, a research team presented an update on the clinical program for HLX02, a proposed trastuzumab biosimilar referencing Herceptin. The proposed biosimilar is being developed by the Chinese firm Shanghai Henlius Biotech.

The researchers reported that, following the stepwise development approach for biosimilars, they enrolled 12 healthy male volunteers to evaluate the safety and tolerability of a single infusion of the biosimilar at 2, 4, 6, and 8 mg/kg. The different concentrations demonstrated acute and dose-dependent effects on serum concentration.

Subsequently, the researchers demonstrated safety and pharmacokinetic equivalence of the biosimilar and its reference in 109 healthy male volunteers who received single infusions of 6 mg/kg of either the biosimilar or US- or EU-licensed reference trastuzumab.

The geometric mean ratios of AUC_0-∞ for HLX02 versus EU trastuzumab, HLX02 versus US trastuzumab, and US trastuzumab versus EU trastuzumab were 0.914 (90% CI, 0.858-0.973), 0.950 (90% CI, 0.891-1.013), and 0.962 (90% CI, 0.902-1.025), respectively, all of which fell within the prespecified bioequivalence margin of 0.80 to 1.25. No deaths, serious adverse events, or antidrug antibodies were observed in any of the groups.

Finally, the researchers initiated a phase 3 study to investigate the efficacy and safety of the biosimilar plus docetaxel versus EU-licensed trastuzumab plus docetaxel in 653 female patients with HER2-positive breast cancer at 83 centers in China, Poland, Ukraine, and the Philippines. The phase 3 study is ongoing, say the authors, who note that HLX02 is the first China-manufactured trastuzumab biosimilar to be investigated in a global trial setting.

Reference

Zhang Q, Xu B, Zhang Q, et al. Global clinical trials validating bioequivalence with China-manufactured trastuzumab biosimilar. Presented at: European Society for Medical Oncology Asia 2018 Congress; November 23-25, 2018; Singapore. Abstract 44P. cslide.ctimeetingtech.com/asia2018/attendee/confcal/session/calendar?q=biosimilar.