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ELISA Assay Kits for Therapeutic Antibodies

Pharmacokinetics (PK) is a branch of science dedicated to the quantitative analysis of absorption, distribution, metabolism and excretion of drug molecules within the body of a living organism. All pre-clinical and clinical studies include the measurement of serum drug concentration, both in animals and in patients, at different points after drug administration. The result is an important indicator of the drug’s pharmacokinetic properties, and is pertinently relevant to dosing recommendations.

The booming market of biologic drugs, driven by a flurry of success with monoclonal antibodies, brings the need for standard high throughput assays to evaluate the content of mAbs in serum samples. Traditionally, the analyses are conducted by indirect ELISA, or with the help of anti-drug antibodies (ADA), each with its own pros and cons. We have developed a series of assays based on the competitive ELISA method. The assay employs a biotinylated mAb against the same target as a tracer to compete with the unlabeled analyte, and uses the interaction between biotin and streptavidin for the eventual readout. This method does not rely on ADAs, and it also alleviates the background issue often occurred with the traditional assay format.

We have launched kits for the studies of CTLA-4, PD-1, and HER-2, respectively, in both humans, and common experimental animals.

Product List

Cat. No.	Product Description	Size
EPH-V1	ELISA Assay Kit for Anti-PD-1 h-mAb in Human Serum	96/480 tests
EHM-V1	ELISA Assay Kit for Anti-HER-2 h-mAb in Mouse Serum	480 tests

Coming Soon

ELISA Assay Kit for Adalim*mab in Serum ELISA Assay Kit for Bevaciz*mab in Serum ELISA Assay Kit for Ritux*mab in Serum ELISA Assay Kit for Cetux*mab in Serum

If you don’t find a easy to use kit, we can provide services for you!

Product Features

Low Background

The serum samples contain many factors that may potentially interfere with the indirect ELISA result. This is the major reason for the background issue (Fig. 1A). Therefore, a series of testing need to be performed to determine the minimum required dilution (MRD) before an experiment can be conducted. This can be time consuming and the results can vary. On the other hand, the competitive ELISA method we employed for our kit does not have a background issue. As shown in Fig 1B, dilutions up to 1:5 does not produce any background at all.

Fig. 1 Background comparison between indirect and competitive ELISA with samples of different dilutions. A: Indirect ELISA; B: Competitive ELISA. (Serum sample from Cancer Institute & Hospital. Chinese Academy of Medical Sciences GCP Centre).

Application

The assay kits can be used for studies of any mAbs share similar binding domain as our tracer biotinylated antibody.

For example, with our Anti-PD-1 mAb kit for human serum samples(Cat. No. EPH-V1), we have successfully measured five different anti-PD1 mAbs that are either on the market already or being tested in clinical trials.

Name	Pembrolizum*b	Nivol*mab	Therapeutic PD-1 Antibody J, Human IgG4	Therapeutic PD-1 Antibody X, Human IgG4	Therapeutic PD-1 Antibody H, Human IgG4
Detection Range (μg/ml)	0.03125-20	0.03125-20	0.03125-20	0.03125-20	0.03125-20
Sensitivity (μg/ml)	0.15625	0.15625	0.15625	0.15625	0.15625
%Recovery	88-113	92-114	86-114	96-112	87-106

Fig. 2 Determination of serum drug concentration for five PD-1 therapeutic antibodies using PD-1 ELISA Kit

High Batch-to-Batch Consistency

We install rigorous quality control program to ensure the lot-to-lot consistency of our products. Every batch of products are analyzed against our internal standards using various analytical methods. The product will be released only if all standards are met.

High Stability

All kits components are analyzed for their stability using accelerated testing method. Based on the results shown in Fig. 3, the products can be stored at -80 for 4-6 months. The assay components are also tested after one or two freeze-thaw cycles. No significant activity loss was observed under either conditions.

Fig. 3 ELISA using Anti-PD-1 h-mAb kit Human Serum (Cat. No. EPH-V1). The samples were incubated at 37℃ for 2 hours after reconstitution. No significant loss of activity was observed.

Fig. 4 ELISA using Anti-PD-1 h-mAb kit Human Serum (Cat. No. EPH-V1). The samples were subjected to zero, one, and two rounds of freeze-thawing cycles, respectively. No significant loss of activity was observed.

For more information

1. Quantitative Analysis of mAb in Serum

FAQ

What specific drug analytes and sample matrices do these therapeutic-antibody PK kits measure?

The ACROBiosystems therapeutic-antibody PK kits are engineered to quantify selected therapeutic monoclonal antibodies within biological fluids. Available options in the catalog include an anti-PD-1 PK kit optimized for human serum and an anti-HER2 PK kit optimized for mouse serum. Please verify the exact target and specified sample matrix before planning your assay.

How does the competitive assay generate a readout?

A biotinylated tracer antibody competes with unlabeled analyte, and streptavidin-based detection provides the readout.

Which therapeutic-antibody PK kits are available?

Options include an anti-PD-1 kit for human serum and an anti-HER2 kit for mouse serum.

Can the anti-PD-1 PK kit detect more than one antibody?

Five anti-PD-1 antibodies with binding domains similar to the tracer were tested. Confirm compatibility with your antibody.

Why use competitive ELISA for therapeutic-antibody PK measurements?

The format can reduce serum-related background compared with indirect ELISA. Validate background and dilution for the intended antibody and matrix.

What critical technical parameters must be verified before planning a PK study sampling workflow?

To secure flawless assay execution and guarantee valid pharmacokinetic profiling data, researchers must cross-verify the following parameters before final sample collection: target species compatibility, therapeutic-antibody binding domain alignments, the kit’s exact linear detection range, optimal sample dilution factors, and study-specific sample handling or storage guidelines.

What are the recommended storage conditions and shelf-life stability profiles for these kits?

ACROBiosystems PK assay kit should be stored at -25°C to -15°C. Once opened, the individual components must be stored strictly according to the provided components table, with an opened shelf life of 30 days from the date of opening. Always check the expiration date on the outside packaging and avoid using reagents past that date.

Introduction
Product List
Product Features
FAQ