Cofetuzumab is a humanized immunoglobulin G1 kappa (IgG1κ) monoclonal antibody engineered to target the cell surface protein tyrosine kinase 7 (PTK7). This protein belongs to the catalytically inactive receptor tyrosine kinase family and is involved in cellular processes such as signaling, adhesion, and migration. Structurally, the antibody component of Cofetuzumab has the classical Y-shaped configuration composed of two identical heavy chains and two identical light chains connected by disulfide bonds, with a molecular weight typical of full-length IgG1 antibodies (around 150 kilodaltons). It is produced in mammalian expression systems, such as Chinese Hamster Ovary (CHO) cells, to ensure correct folding and glycosylation patterns.
The antibody portion contains variable domains (VH and VL) with complementarity-determining regions (CDRs) that bind specifically to epitopes on PTK7. These binding sites direct the antibody to PTK7-expressing cell membranes, enabling molecular selectivity through non-covalent interactions including hydrogen bonding and hydrophobic contacts. Therapeutically, Cofetuzumab is designed as an antibody-drug conjugate (ADC), meaning it is covalently linked—via a specialized chemical linker—to a potent cytotoxic payload, in this case pelidotin, a microtubule-disrupting agent derived from auristatin analogs. The linker connecting pelidotin to the antibody is cleavable within the cellular environment, allowing targeted drug release upon internalization.
InnoCyto biosimilars are research-grade recombinant antibodies or proteins engineered to closely replicate the sequence, structure, and target-binding activity of approved or well-characterized therapeutic antibodies (e.g., checkpoint inhibitors, anti-cytokine biologics). They are intended for research use to study the mechanism of action, efficacy, and combination potential of these therapeutic classes without the cost or access restrictions of clinical-grade material.
How similar are these biosimilars to the original therapeutic antibody?
Each biosimilar is produced using the published or inferred variable region sequence of the reference therapeutic and is expressed recombinantly to match the parent antibody's target specificity, isotype, and general binding profile. While designed for high functional similarity, InnoCyto biosimilars are for research use only and are not clinically validated equivalents of the approved drug product.
Are these antibodies suitable for in vivo studies?
Yes. InnoCyto biosimilars are manufactured with the same low-endotoxin, azide-free, carrier-free standards used across our in vivo product lines, making them suitable for animal efficacy, combination, and mechanism-of-action studies. Product pages indicate whether a given biosimilar is validated for in vivo use, in vitro use, or both.
What is the difference between a biosimilar and a recombinant "research antibody" targeting the same protein?
A biosimilar is specifically designed to mimic a known, named therapeutic antibody (matching its clinical target epitope and mechanism), whereas a general recombinant research antibody may target the same protein but bind a different epitope or lack the same functional properties. Biosimilars are the right choice when your study is benchmarking against, or modeling the action of, an approved or clinically studied biologic.
What quality and purity standards do biosimilar antibodies meet?
All biosimilars undergo the same rigorous QC pipeline as our other antibody lines: ≥95% purity by SDS-PAGE/SEC-HPLC, low-endotoxin testing via LAL assay, and binding/functional validation against the intended target. Certificates of Analysis (CoA) are provided per lot with full specifications.
Which therapeutic targets and mechanisms are covered in the Biosimilar line?
The line spans major immuno-oncology and immunology targets, including immune checkpoint pathways (e.g., PD-1/PD-L1, CTLA-4), cytokine and cytokine-receptor blockers, and other clinically relevant mechanisms. See each product page for the specific reference therapeutic and mechanism of action represented.
Have a product or application question? Consult our FAQs or contact us.
