Comparative nonclinical assessments of the biosimilar PF-06410293 and originator adalimumab.

Adalimumab, a recombinant fully human monoclonal antibody targeting tumor necrosis factor (TNF), is approved in the United States and Europe to treat various inflammatory and autoimmune indications. Biosimilars are approved biologics highly similar, but not identical, to approved biotherapeutics. To support clinical development of PF-06410293, an adalimumab biosimilar, nonclinical studies evaluated the structural, functional, toxicologic, and toxicokinetic similarity to originator adalimumab sourced from the United States (adalimumab-US) and European Union (adalimumab-EU). Structural similarity was assessed by peptide mapping. Biologic activity was measured via inhibition of TNF-induced apoptosis and Fc-based functionality assessments. In vivo nonclinical similarity was evaluated in a toxicity study in cynomolgus monkeys administered subcutaneous PF-06410293 or adalimumab-EU (0 or 157 mg/kg/week). Peptide mapping demonstrated PF-06410293, adalimumab-US, and adalimumab-EU had identical amino acid sequences. Comparative functional and binding assessments were similar. Effects of PF-06410293 and adalimumab-EU were similar and limited to pharmacologically mediated decreased cellularity of lymphoid follicles and germinal centers in spleen. Toxicokinetics were similar; maximum plasma concentration and area-under-the-concentration-time curve ratio of PF-06410293:adalimumab-EU ranged from 1.0 to 1.2. These studies supported PF-06410293 entry into clinical development. Many regulatory agencies now only request nonclinical in vivo testing if there is residual uncertainty regarding biosimilarity after in vitro analytical studies.

Nonclinical Evaluation of PF-06438179: A Potential Biosimilar to Remicade® (Infliximab).

INTRODUCTION: PF-06438179, a potential biosimilar to Remicade® (infliximab, Janssen Biotech, Inc.), is a chimeric mouse-human monoclonal antibody targeting human tumor necrosis factor alpha (TNF). METHODS: Analytical (small subset reported here) and nonclinical studies compared the structural, functional, and in vivo nonclinical similarity of PF-06438179 with Remicade sourced from the United States (infliximab-US) and/or European Union (infliximab-EU). RESULTS: The peptide map profiles were superimposable, and peptide masses were the same, indicating identical amino acid sequences. Data on post-translational modifications, biochemical properties, and biological function provided strong support for analytical similarity. Administration of a single intravenous (IV) dose (10 or 50 mg/kg) of PF-06438179 or infliximab-EU to male rats was well tolerated. There were no test article-related clinical signs or effects on body weight or food consumption. Systemic exposures [maximum drug concentration (C max) and area under the concentration-time curve (AUC)] in rats administered PF-06438179 or infliximab-EU were similar, with mean exposure ratio of PF-06438179 relative to infliximab-EU ranging from 0.88 to 1.16. No rats developed anti-drug antibodies. A 2-week IV toxicity study was conducted with once-weekly administration of 10 or 50 mg/kg of PF-06438179 to male and female rats. PF-06438179-related hyperplasia of sinusoidal cells occurred in the liver in rats administered 50 mg/kg, but was not adverse based on its minimal to mild severity. The no-observed adverse-effect level for PF-06438179 was 50 mg/kg. At this dose, C max was 1360 µg/mL and AUC at 168 h was 115,000 µg h/mL on day 8. CONCLUSIONS: The analytical and nonclinical studies have supported advancement of PF-06438179 into global comparative clinical trials. FUNDING: Pfizer Inc.

Comparative nonclinical assessments of the proposed biosimilar PF-05280014 and trastuzumab (Herceptin(®)).

BACKGROUND AND OBJECTIVES: Trastuzumab (Herceptin(®)) is a humanized monoclonal antibody (mAb) that binds to the HER2 protein. PF-05280014 is being developed as a potential biosimilar to trastuzumab products marketed in the United States (trastuzumab-US) and European Union (trastuzumab-EU). Nonclinical studies were designed to evaluate the similarity of PF-05280014 to trastuzumab-US and trastuzumab-EU using in vitro structural and functional analyses, and in vivo pharmacokinetic and immunogenicity assessments. METHODS: Peptide mapping was utilized to determine structural similarity. Functional similarity was assessed via an in vitro tumor cell growth inhibition assay. CD-1 male mice were administered a single-dose (0, 1, 10, or 100 mg/kg) of PF-05280014, trastuzumab-US, or trastuzumab-EU. Mice were monitored for clinical signs and body weight changes over a 4-month period. At approximately 720, 1,080, 1,440, 2,160, and 2,880 h post-dose, terminal blood samples were collected and assayed for PF-05280014, trastuzumab-US, or trastuzumab-EU concentrations and anti-drug antibodies (ADA). Values for C max, area under the concentration time curve (AUC), clearance (CL), volume of distribution (V ss), half-life (t ½), and the presence of ADA were determined. RESULTS: In this report, peptide mapping of PF-05280014, trastuzumab-US, and trastuzumab-EU showed similar chromatographic profiles in a side-by-side analysis. The tumor cell growth inhibition of PF-05280014 was similar to trastuzumab-US and trastuzumab-EU. C max and AUC0-∞ values in mice were similar and dose-dependent across the mAbs at all doses, and CL and V ss values were similar and dose-independent. The CL values across doses ranged from 0.193 to 0.350 mL/h/kg (PF-05280014), from 0.200 to 0.346 mL/h/kg (trastuzumab-US), and from 0.193 to 0.335 mL/h/kg (trastuzumab-EU). V ss values across doses ranged from 84.9 to 120 mL/kg (PF-05280014), 86.7 to 130 mL/kg (trastuzumab-US), and 85.4 to 116 mL/kg (trastuzumab-EU). The incidence of ADA was low (~10%) and also similar across all dose levels and the three mAbs. The lower exposure generally observed in ADA-positive animals did not impact the overall PK interpretation. All animals survived to their scheduled terminal blood collection with no mAb-related differences in body weight gain or clinical signs. CONCLUSIONS: PF-05280014, trastuzumab-US, and trastuzumab-EU were well tolerated during the 4-month observation period following a single dose of up to 100 mg/kg. PF-05280014, trastuzumab-US, and trastuzumab-EU showed similar structural properties, tumor cell growth inhibition properties, and PK profiles. The incidence of ADA was low and similar across the three mAbs. The results of these studies support the development of PF-05280014 as a proposed biosimilar to Herceptin.