A randomized phase 1 pharmacokinetic trial comparing the potential biosimilar PF-05280014 with trastuzumab in healthy volunteers (REFLECTIONS B327-01).

AIMS: The pharmacokinetic (PK) similarity between PF-05280014, a proposed trastuzumab biosimilar, trastuzumab sourced from European Union (trastuzumab-EU) or from United States (trastuzumab-US) was evaluated. Safety and immunogenicity were also assessed. METHODS: In this phase 1, double-blind trial (NCT01603264), 105 healthy male volunteers were randomized 1:1:1 to receive a single 6 mg kg(-1) intravenous dose of PF-05280014, trastuzumab-EU, or trastuzumab-US, and evaluated for 70 days. Drug concentration-time data were analyzed by non-compartmental methods. PK similarity for the comparisons of PF-05280014 to each of trastuzumab-EU and trastuzumab-US, and trastuzumab-EU to trastuzumab-US were determined using the standard 80.00% to 125.00% bioequivalence criteria. RESULTS: Baseline demographics for the 101 subjects evaluable for PK were similar across all arms. The three products exhibited similar PK profiles with target-mediated disposition. The 90% CIs for the ratios of Cmax , AUC (0 , t last) and AUC(0,∞) were within 80.00% to 125.00% for all three pairwise comparisons. Adverse events (AEs) were similar across all arms with treatment-related AEs reported by 71.4%, 68.6% and 65.7% subjects in the PF-05280014, trastuzumab-EU, and trastuzumab-US arms, respectively. The most common AEs were infusion-related reactions, headache, chills, pyrexia and nausea. The AE term 'pyrexia' was numerically greater in the PF-05280014 arm. All post-dose samples, except 1, tested negative for anti-drug antibodies (ADA). CONCLUSIONS: This study demonstrates PK similarity among PF-05280014, trastuzumab-EU and trastuzumab-US. The safety and immunogenicity profiles observed for the three products in this study are consistent with previous reports for trastuzumab.

Biosimilars for breast cancer: a review of HER2-targeted antibodies in the United States.

The utilization of trastuzumab biosimilar medications is of particular interest in HER2-positive breast cancer as these drugs have the potential for cost savings and increased utilization/access to HER2 targeted therapy in both early stage and metastatic HER2-positive breast cancers. Five trastuzumab biosimilars: MYL-1401O (Ogivri), CT-P6 (Herzuma), SB3 (Ontruzant), PF-05280014 (Trazimera), and ABP980 (Kanjinti), have now been approved by the US Food and Drug Administration (FDA) for use in HER2-positive breast cancers. This review provides an overview of these agents with special consideration of the development and approval process, including available clinical data results for these trastuzumab biosimilars. Adoption in the clinic will depend on the degree of comfort with the overall evidence.