Functional and Nonclinical Similarity of ABP 980, a Biosimilar of Trastuzumab

Real-world clinical scenarios during introduction of trastuzumab biosimilar for HER2-positive breast cancer in the European Union

Aim: Trastuzumab-anns is an intravenously administered biosimilar to trastuzumab approved by the EMA and US FDA for treatment of HER2+ early and metastatic breast cancer as well as metastatic gastric cancer. Lack of real-world characterization of biosimilar use has hindered uptake. Methods: This observational chart review characterizes 488 patients who received trastuzumab-anns in EU clinical practice settings. Results: Approximately 2/3rds of patients initiated trastuzumab-anns in adjuvant and neoadjuvant settings and most were naive new starters (70%). 30% were switchers from another trastuzumab, among whom 48% switched from trastuzumab iv. reference product. Common reasons for trastuzumab-anns discontinuation were a switch to another biosimilar product (34.8%, n = 85) or to trastuzumab reference product (15.6%, n = 38). Conclusion: Trastuzumab-anns was widely used in various treatment settings for HER2+ breast cancer.

Systematic Review on the Use of Biosimilars of Trastuzumab in HER2+ Breast Cancer

Trastuzumab is a monoclonal antibody used in the treatment of breast cancer in cases where the tumor overexpresses the HER2 receptor, a cell membrane receptor activated by the epidermal growth factor. Intravenous and subcutaneous administration of trastuzumab have comparable clinical and pharmacological characteristics, but trastuzumab biosimilars are currently only available in intravenous form. Trastuzumab biosimilars are ultimately preferred by a proportion of patients, especially in cases where co-administration of other chemotherapeutic agents, such as trastuzumab and tucatinib, a small molecule of tyrosine kinase inhibitor, is required in patients with HER-positive metastatic breast cancer. Oncologists should be well-aware of the advantages of intravenously administered trastuzumab biosimilars over subcutaneous administration, certainly also taking into account the patient’s preferences. Further cost-effectiveness analyses will be very important, along with expectations regarding successful concomitant subcutaneous administration of trastuzumab with other anticancer drugs, such as pertuzumab. This systematic review describes and analyzes the so-far published studies concerning the use of the available trastuzumab biosimilars in HER-positive early and metastatic breast cancer in terms of efficacy, safety, and cost–benefit ratio. An attempt was also made to draw some conclusions and to comment on future needs and perspectives.

Utility of SPR technology in biotherapeutic development: Qualification for intended use

Surface plasmon resonance (SPR) analysis provides important binding characteristic information for an antibody to its binding partner, such as binding specificity and affinity (K_D). In recent years, SPR has been increasingly used in biosimilar development as part of the comparative analytical similarity assessment. Although there is no systematic study describing how to qualify SPR assays, there are various SPR result types (outputs) that have been used for assay qualification in publicly available regulatory documents. The mixed usage of SPR output can cause confusion and can be misleading when comparing binding attributes among antibody molecules. In this report, using a recombinant huIgG1 (mAb 1) antibody as an example, we performed assay qualification strictly based on the nature of the biomolecular interaction. We recommend that K_D should be used as the output of assay qualification when the K_D can be measured accurately by SPR. When K_D cannot be accurately determined in a SPR setting, sensorgram comparison and Parallel Line Analysis (PLA) can be used to qualify the assay. We emphasize the importance of setting up appropriate SPR assay conditions for target and/or Fc receptor interactions to ensure the assay qualification parameters, such as accuracy and repeatability, to meet the criteria acceptable for regulatory filings. With increasing numbers of biotherapeutics being developed, the methods and guidelines provided here can help to align SPR application between the drug development industry and regulatory authorities which will benefit the scientific communities involved in biotherapeutic drug development.

Antigen improves binding of IgGs to FcγRs in SPR analysis

FcγR binding characterization is one of the critical attributes during the development of therapeutic antibodies. Here, we report a novel assay format to characterize IgG-FcγR interaction in the presence of antigen using Surface plasmon resonance (SPR). The new assay format was developed by creating stable antigen/antibody immunocomplexes on a sensor chip surface before injection of FcγRs. In this assay format, binding activity of both huIgG1 (including IgG1 Fc fusion Protein) and huIgG2 increased significantly to most activating human FcγRs, especially to FcγRI, FcγRIIa-131H and FcγRIIIa-158F. To our knowledge, this study provides the first set of evidence using a biophysical method to demonstrate antigen binding facilitating IgG-FcγR interaction, especially for huIgG2 where previous studies did not indicate its binding to human FcγRI or FcγRIIIa-158F. Although further studies are needed to investigate the correlation of the binding data with effector function data in vivo, our results suggest that it may be useful to evaluate the IgG-FcγR interaction in the presence of antigen to help design safer and more effective biotherapeutics.

Spacer length and serum protein adsorption affect active targeting of trastuzumab-modified nanoparticles

Receptor-mediated active targeting of nanocarriers is a widely investigated approach to specifically address cancerous cells and tissues in the human body. The idea is to use these formulations as drug carriers with enhanced specificity and therefore reduced systemic side effects. Until today a big obstacle to reach this goal remains the adsorption of serum proteins to the nanocarrier's surface after contact with biological fluids. In this context different nanoparticle characteristics could be beneficial for effective active targeting after formation of a protein corona which need to be identified. In this study trastuzumab was used as an active targeting ligand which was covalently attached to human serum albumin nanoparticles. For coupling reaction different molecular weight spacers were used and resulting physicochemical nanoparticle characteristics were evaluated. The in vitro cell association of the different nanoparticle formulations was tested in cell culture experiments with or without fetal bovine serum. For specific receptor-mediated cell interaction SK-BR-3 breast cancer cells with human epidermal growth factor receptor 2 (HER2) overexpression were used. MCF-7 breast cancer cells with normal HER2 expression served as control. Furthermore, serum protein adsorption on respective nanoparticles was characterized. The qualitative and quantitative composition of the protein corona was analyzed by SDS-PAGE and LC-MS/MS and the influence of protein adsorption on active targeting capability was determined.

Totality of Evidence Supporting the Use of ABP 980, a Trastuzumab Biosimilar: Practical Considerations

ABP 980 (KANJINTI™, Amgen, Thousand Oaks, CA, USA; Amgen Europe B.V., The Netherlands) is a biosimilar to trastuzumab (Herceptin^®), a monoclonal antibody that selectively binds human epidermal growth factor receptor-2 (HER2). Here we provide a brief overview of the totality of evidence (including analytical [structural and functional] characterization, nonclinical evaluation, and human pharmacokinetic [PK], pharmacodynamic, and clinical assessment comparing ABP 980 with trastuzumab reference product [RP]) that supported the approval of ABP 980, along with practical considerations on the reconstitution and use of the lyophilized product to ensure safe and effective administration. ABP 980 has been shown to be highly similar to the RP, with similar mechanism of action, binding, and potency. Key PK parameters, geometric means ratio (GMR [90% CI]) of C_max and AUC_inf, are comparable and within the equivalence margin of 0.80 to 1.25 (ABP 980: 1.04 [0.99–1.08] versus trastuzumab US: 1.06 [1.00–1.12]; ABP 980: 0.99 [0.95–1.03] versus trastuzumab EU: 1.00 [0.95–1.06]). No clinically meaningful differences were found between ABP 980 and RP in a comparative clinical trial in patients with HER2-positive early breast cancer. Pathological complete response—ABP 980: 48% versus RP: 41% (risk difference [RD], 90% CI: 7.3%, 1.2–13.4; relative risk [RR], 90% CI: 1.188, 1.033–1.366). Sensitivity analyses per central pathology review—ABP 980: 48%; RP: 42% (RD: 5.8%, −0.5 to 12.0; RR: 1.142, 0.993–1.312), with RD and RR falling within predefined equivalence margins. Similar to trastuzumab RP, KANJINTI™ is supplied as a sterile, lyophilized cake to be reconstituted with bacteriostatic water for injection (BWFI) for multiple-dose injection or sterile WFI for single use. Stability data support storage of reconstituted solution at 2–8°C (36–46°F), up to 28 days. Reconstituted solution can be diluted in infusion bags containing 0.9% saline and stored for up to 24 h prior to intravenous administration.

Clinical and treatment characteristics of patients treated with the first therapeutic oncology biosimilars bevacizumab-awwb and trastuzumab-anns in the US

Background:

In July 2019, bevacizumab-awwb and trastuzumab-anns were marketed in the USA as the first therapeutic oncology biosimilars. We aimed to investigate the initial real-world use of bevacizumab-awwb and trastuzumab-anns for cancer management in US oncology practices.

Methods:

A retrospective, observational analysis of data from US cancer patients (⩾18 years of age) was carried out to describe the use of bevacizumab-awwb and trastuzumab-anns during the first 12 months following their market entry, using structured data from the Flatiron Health electronic health record-derived database.

Results:

A total of 2952 and 2997 patients with recorded use of bevacizumab-awwb and trastuzumab-anns, respectively, were included in the analysis. The first use of bevacizumab-awwb and trastuzumab-anns was in a patient with metastatic colorectal cancer (mCRC) within 10 days of market availability and in a patient with early stage breast cancer (eBC) within 4 days, respectively. The use of these biosimilars was observed across all approved cancer indications; 68% of bevacizumab-awwb users were those diagnosed with mCRC and 72% of trastuzumab-anns users were those diagnosed with eBC. Approximately half the patients were previously exposed to reference product (RP) prior to initiation of bevacizumab-awwb or trastuzumab-anns. Among pre-exposed patients, the majority received the biosimilars [bevacizumab-awwb (63–85%) or trastuzumab-anns (75–81%)] within 28 days of the last infusion of the RP. For both biosimilars, no major differences were observed in patient characteristics between RP-naïve and pre-exposed patients.

Conclusion:

Initial evidence from the first 12 months following market entry suggests rapid clinical adoption of bevacizumab-awwb and trastuzumab-anns across all approved tumor types. Usage of these two biosimilars was observed in both RP-naïve patients and patients who were previously treated with RP, with no distinctive differences in patient characteristics between the two groups.

A video abstract is available for this article as part of the Kanjintionline supplemental material.

Totality of Scientific Evidence in the Development of ABP 980, a Biosimilar to Trastuzumab

ABP 980 was developed as a biosimilar to trastuzumab, a monoclonal antibody targeting human epidermal growth factor receptor 2 (HER2), that is indicated for the treatment of HER2-positive metastatic breast cancer, early breast cancer (EBC), and metastatic gastric cancer. ABP 980 is approved in the United States, European Union, and Japan for all the indications of trastuzumab, based on the totality of evidence (TOE) gathered by the systematic step-wise accumulation of comparative analytical, preclinical, and clinical (pharmacokinetics [PK], efficacy, safety and immunogenicity) data for ABP 980 and trastuzumab reference product (RP). As a key first step of the ABP 980 biosimilar program, comprehensive analytical characterization of critical quality attributes established that ABP 980 is structurally and functionally similar to trastuzumab RP. Complementing these data, results of non-clinical pharmacology, toxicology, and toxicokinetic studies supported similarity between ABP 980 and trastuzumab RP. A randomized study in healthy subjects demonstrated clinical PK equivalence of ABP 980 relative to trastuzumab RP in these subjects. In the final clinical evaluation step, a randomized comparative study (LILAC) confirmed the lack of clinically meaningful differences between ABP 980 and trastuzumab RP in efficacy, safety, and immunogenicity in women with HER2-positive EBC in the neoadjuvant–adjuvant setting. Neoadjuvant EBC represented a sensitive homogenous population for biosimilar demonstrations, and the primary endpoint of pathologic complete response served as a sensitive surrogate endpoint. An important aspect of the LILAC study design is that it is the only study that evaluated the effect of switching from the trastuzumab RP to a trastuzumab biosimilar during the adjuvant phase. No new or unexpected safety signals emerged in the clinical evaluations, with the safety profile of ABP 980 consistent with that previously described for trastuzumab. Overall, the TOE data generated for ABP 980 support the conclusion that it is highly similar to trastuzumab RP, thus providing the scientific justification for extrapolation to all the approved indications of trastuzumab.