Abstract
BACKGROUND: Pertuzumab is a humanized monoclonal antibody for the treatment of breast cancer. HLX11 is a biosimilar of pertuzumab developed by Shanghai Henlius Biotech, Inc. We conducted a bioequivalence study for HLX11 and pertuzumab (United States [US]-, European Union [EU]-, and China [CN]-approved products). OBJECTIVES: This study compared the biosimilarity in pharmacokinetics (PK), safety, and immunogenicity between HLX11 and reference pertuzumab (approved in the US, the EU, and CN) in healthy Chinese male participants after a single infusion and further characterized the PK profile of HLX11. METHODS: Eligible individuals were randomized 1:1:1:1 to receive a single dose of 420 mg HLX11, US-, EU-, or CN-pertuzumab via intravenous infusion over 60 min. The primary endpoints were maximum serum drug concentration (C(max)), area under the serum concentration-time curve (AUC) from time 0 to time of the last quantifiable concentration (AUC(0-t)), and AUC from time 0 to infinity (AUC(0-∞)). PK bioequivalence was established if the 90% confidence intervals (CIs) of the geometric mean ratios of the primary endpoints were between 80.0 and 125.0%. Secondary endpoints included other PK parameters, safety, and immunogenicity. RESULTS: A total of 160 participants were enrolled and randomly assigned to each group (n = 40 per group). The 90% CIs of the geometric mean ratios of the primary endpoints were all within the prespecified equivalence margins (HLX11 vs. pertuzumab [US-, EU-, CN-approved products]: C(max) 97.03-115.06%, 91.39-109.80%, 94.53-110.65%; AUC(0-t) 87.65-99.68%, 87.07-100.79%, 86.29-101.09%; AUC(0-∞) 87.66-99.90%, 87.54-101.05%, 89.23-103.20%). The incidence of adverse drug reactions was comparable across the four groups. The presence of anti-drug antibodies or neutralizing antibodies had no obvious effect on PK. CONCLUSION: The PK, safety, and immunogenicity of HLX11 were highly similar to those of reference pertuzumab (US-, EU-, CN-approved products). The established bioequivalence supports further clinical trials of HLX11 in cancer treatment. TRIAL REGISTRATION: This study was registered with ClinicalTrials.gov (NCT04411550) and Chinadrugtrials.org.cn (CTR20200618).