Accelerō® Bioanalytics - Good Laboratory Practice (GLP) Compliant


The Ligand Binding Assay

When pharmaceutical companies are developing new drugs, it has become a common practice to outsource the necessary bioanalytical work to Contract Research Organizations (CROs) that are Good Laboratory Practice (GLP) compliant, such as Accelerō® Bioanalytics. Ligand binding assay work represents one of the key quantitative methods in immunogenicity and biomarker studies for new microRNA therapies.

A ligand binding assay depends upon the binding of an analyte to an assay reagent, which facilitates the quantification of such macromolecules as proteins and olginucleotides in a given sample. While it is certainly possible for pharmacology firms to perform a ligand binding assay in-house, several factors make it more economical to outsource ligand binding assay work to an FDA Good Laboratory Practice (GLP) compliant CRO.

Outsourcing Ligand Binding Assay Work to a Good Laboratory Practice GLP Facility

Different levels of outsourcing are possible depending on the groundwork already done by the pharmaceutical concern. Ligand binding assay outsourcing may simply be a transfer of a firm’s pre-developed procedure that a Good Laboratory Practice (GLP) compliant contract lab adopts and carries out according to the ligand binding assay client’s specifications.

In other cases, the CRO may start with the pharmaceutical development company’s protocol and optimize the ligand binding assay method to fit a different species matrix. The Good Laboratory Practice (GLP) mandates may cause a CRO to modify a client’s ligand binding assay methodology to ensure compliance.

Another option for a drug development company that has built a working relationship with a Good Laboratory Practice (GLP) compliant contract research laboratory, such as Accelerō® Bioanalytics, is to entrust the entire ligand binding assay process to the expertise of lab personnel. Plenty of experience plus a track record of delivering accurate and well-documented ligand binding assay results, according to Good Laboratory Practice (GLP) standards, are two decisive factors in the client’s decision to outsource a ligand binding assay series.

Advantages of Ligand Binding Assay Outsourcing

CROs can provide an on-call personnel forces for pharmaceutical concerns that do not have the resources to employ ligand binding assay technicians full-time. A Good Laboratory Practice (GLP) compliant contract lab, like Accelerō® Bioanalytics, has already invested the extra time and cost to ensure that every ligand binding assay it does for a client yields accurate, reproducible results, thus saving clients the expense of creating their own Good Laboratory Practice (GLP) facility.

Another important advantage of outsourcing ligand binding assay development, analysis and validation is that, by entrusting the work to an experienced, Good Laboratory Practice (GLP) CRO, a drug development firm can focus on those aspects of the bioanalytical process that staff members are well qualified to do. The end result will be more efficient development of microRNA and other therapies within a shorter time frame, and within the specifications of Good Laboratory Practice( GLP).

By establishing a strong working relationship with a Good Laboratory Practice (GLP) lab such as Accelerō® Bioanalytics, a drug development company is cultivating an important resource that can step in to provide backup support for any in-house lab backlogs as well as deliver the Good Laboratory Practice (GLP) data critical to moving forward towards drug approval.


The Ligand Binding Assay

A ligand is a substance that binds with a target biomolecule. In the Good Laboratory Practice (GLP) facility, a ligand serves as a signal triggering molecule that binds to a protein, revealing specific test results. Various ligand binding assay applications may utilize ligands that are substrates, inhibitors, activators, or neurotransmitters. Their binding property, or the strength of the bond formed, is called its affinity.

A ligand binding assay, carried out under the strict standards of Good Laboratory Practice (GLP), can determine the binding affinity between a ligand and its receptor molecule. The strength of the affinity becomes relevant when the energy created by a high affinity ligand bond can be directed toward causing a change in reception conformation, which alters the behavior of an associated enzyme.

A ligand that behaves in this way, changing its receptor and triggering a behavioral response, is called an agonist. By helping researchers to determine the level of affinity between a ligand and its receptor, a Good Laboratory Practice (GLP) compliant ligand binding assay reveals the optimum concentration of the agonist for triggering the intended physiological response, thus providing data important to determining dosages of microRNA drugs.

>A ligand binding assay can also determine ligand efficacy -- the biological effect and the magnitude of the effect when the ligand binds to its receptor. Efficacy is another critical factor in dosage determination. Only a Good Laboratory Practice (GLP) compliant CRO, such as Accelerō® Bioanalytics, is fully qualified to perform a ligand binding assay that provides the most accurate, reproducible, and meticulously tracked results.

By carrying out ligand binding assay support in an FDA certified, Good Laboratory Practice (GLP) environment, Accelerō® Bioanalytics produces indispensable, reproducible data for pharmacokinetic assessment purposes in the development of biomarkers and detection of immunogenicity, accelerating the progress of essential new drug therapies towards FDA approval.

Ligand Binding Assay Basics

Different types of the ligand binding assay performed in a Good Laboratory Practice (GLP) environment include the sandwich hybridization assay, ligation-based hybridization, and Real-Time RT-qPCR. With the exponential growth of nucleic acid therapies, many developers of pharmacokinetic and pharmacodynamic drugs order ligand binding assay work for microRNA and siRNA therapeutics.

Liquid phase ligand binding assay formats include Real-Time RT-qPCR and immunoprecipitation. Solid phase ligand binding assay formats include multiwall plate assays, on-column assays, on-bead assays, filter assays, and membrane assays. With several different formats that each are applicable to specific nucleic acid therapies, the importance of selecting a CRO experienced in all types of ligand binding assay formats, that is Good Laboratory Practice (GLP) compliant, become evident.

Recognizing the need for CROs compliant with Good Laboratory Practice (GLP) to carry out ligand binding assay procedures that focus on developing new nucleic acid drugs, Accelerō® Bioanalytics has devoted several years to developing this specialty. Accelerō® Bioanalytics provides the best possible Good Laboratory Practice (GLP) compliant ligand binding assay work for pharmaceutical research in this field of study.

In general, the CRO will perform the following steps in a ligand binding assay (2), although some Good Laboratory Practice (GLP) facilities, such as Accelerō® Bioanalytics, are able to customize a ligand binding assay to a client’s specifications:

• Reagent assemblage – an experienced Good Laboratory Practice (GLP) facilities can create custom reagents upon request

• Assay format selection

• Optimization of experimental design

• Establishment of ligand binding assay parameters

• Testing of known agonists

• Validation of results

During the pre-study validation phase of the ligand binding assay, a Good Laboratory Practice (GLP) contract research lab will select the appropriate assay format from a variety of commercially-available kits, or will customize the ligand binding assay according to client requirements. Such considerations as the correct selection of reagents with the right stability and specificity for the assay, and the appropriate selection of fluorescent ligand marker labels can be critical to the success of the ligand binding assay.

During the ligand binding assay, validation as required by Good Laboratory Practice (GLP) must be ongoing to ensure that the methods selected for the study remain effective throughout the process. Good Laboratory Practice (GLP) activities, such as monitoring control samples to check the performance of the ligand binding assay, help to ensure high quality results.

1. De Jong,L.A., et. al. Receptor-ligand Binding Assays: Technologies and Applications. December 2005.
Available online at: 2011.
2. Assay Guidance Manual Version 5.0, 2008, Eli Lilly and Company and NIH Chemical Genomics Center.
Available online at: 2008.


Applications for the Ligand Binding Assay

As a quantitative tool, the ligand binding assay centers around the binding of an analyte to an assay reagent. When it comes time to quantify macromolecules like oglinucleotides within a biological matrix, an organization will most likely turn over the ligand binding assay work to a Good Laboratory Practice (GLP) contract research lab such as Accelerō® Bioanalytics.

Before selecting the laboratory to carry out a ligand binding assay, a pharmaceutical development company should verify that, like Accelerō® Bioanalytics, the CRO is fully Good Laboratory Practices (GLP) compliant, ensuring the most accurate and verifiable ligand binding assay results. While many labs may offer the ligand binding assay in their portfolio of services, only a Good Laboratory Practices (GLP) facility complies with FDA standards to do such testing.

The ligand binding assay is often used to quantify specific biomarkers for pharmacodynamic or toxicokinetic purposes. A ligand binding assay may be used to study biomarkers for experimental therapies. Any data resulting from the study must be recorded in compliance with Good Laboratory Practice (GLP) guidelines to meet the highest standards for accuracy and reproducibility.

Macromolecule therapies designed to act against specific target proteins, or receptors, can be combined with one or more other drugs to present a united front against such multifaceted diseases as cancer. A ligand binding assay can measure the efficacy of protein-targeting therapies. The resulting data, subject to the meticulous record-keeping controls of the Good Laboratory Practice (GLP) compliant CRO, such as Accelerō® Bioanalytics, will help pharmaceutical developers evaluate the specificity and selectivity of an experimental nucleic acid therapy.

Good Laboratory Practice (GLP) compliant labs, such as Accelerō® Bioanalytics, are uniquely qualified to perform ligand binding assay studies, both from a Good Laboratory Practice (GLP) standpoint and also by virtue of their experienced staff of immunochemistry experts.

Radioactive and Non-radioactive Ligand Binding Assay

The receptor ligand binding assay determines the nature of receptor-ligand interactions in biological systems and provides valuable quantitative data, gleaned and recorded according to Good Laboratory Practice (GLP) standards, that can be crucial to pharmaceutical progress. The two basic receptor ligand binding assay formats available are radioactive and non-radioactive assays.

By nature, the radioactive ligand binding assay format can be hazardous, posing a danger to the health of the technicians in the laboratory as well as producing radioactive waste. While a lab may be Good Laboratory Practice (GLP) compliant, it does not necessarily possess the facilities to deal with the extra expense of a radioactive ligand binding assay format.

That is why, despite the accurate, reproducible results a radioactive ligand binding assay can produce, Good Laboratory Practice (GLP) CROs often utilize the safer, non-radioactive ligand binding assay format to deliver similarly reliable data.

The non-radioactive ligand binding assay involves the use of fluorescent polarization or fluorescence resonance energy transfer technology that optimizes the ability for the ligand binding assay technician to quantify results. A ligand binding assay that utilizes fluorescent markers is applicable to receptor ligand binding assay formats for the biological screening and quantification of pharmaceuticals (1).

The Importance of Good Laboratory Practice GLP

In a contract research facility, Good Laboratory Practice (GLP) outlines the standards for designing and implementing a ligand binding assay as well as reporting ligand binding assay results. Good Laboratory Practice (GLP) standards are not only applicable to a single study, such as a ligand binding assay, but help shape the infrastructure of the laboratory itself, informing all activities within the lab.

One reason Good Laboratory Practice (GLP) compliance is so important for reputable CROs, such as Accelerō® Bioanalytics, is that pharmaceutical clients can rely upon these standards to assure correct results that can be exactly reproduced in a duplicate ligand binding assay or other Good Laboratory Practice (GLP) study.

CROs like Accelerō® Bioanalytics, which are Good Laboratory Practice (GLP) compliant in all of the work they perform, adhere to the highest industry standards. Clients seeking the most professionally run CRO for the highest caliber of ligand binding assay and other testing results acknowledge the importance of Good Laboratory Practice (GLP) certification.

Elements of Good Laboratory Practice (GLP) Guidelines

Some of the standards set by Good Laboratory Practice (GLP) include:

• Establishment of written Standard Operating Procedures (SOP) within the facility

• Meticulous record keeping that stands the test of time

• Space and management divisions that ensure the integrity of each ligand binding assay or other study, eliminating the chance of cross-contamination

• High-quality instruments that are calibrated and well maintained

• Data retention standards that protect the integrity of test results

• Archive procedural guidelines

History of Good Laboratory Practice GLP

Prior to the mid-1970s, before the creation of Good Laboratory Practice (GLP) guidelines, the U.S. Food and Drug Administration relied on the sponsor – manufacturer – of a drug submitted for FDA approval to verify and present accurate, verifiable data as needed for the approval process. When whistle blowers called the test data of several labs into question, FDA laboratory inspections revealed falsification of results and defects in the design and reporting of studies meant to substantiate claims of candidate drug efficacy and safety.

The FDA established Good Laboratory Practice (GLP) regulations in 1976 as a result of these revelations. Several years later, the U.S. Environmental Protection agency adopted the Good Laboratory Practice (GLP) regulations to govern testing procedures for industrial and agricultural chemicals.

Enforcement of Good Laboratory Practice GLP

Once a CRO like Accelerō® Bioanalytics earns the Good Laboratory Practice (GLP) designation, it must maintain the stringent practices that the guidelines proscribe. The FDA routinely carries out bi-annual facility inspections to verify continued Good Laboratory Practice (GLP) compliance in each designated laboratory.

The FDA inspector identifies, notes and discusses deviations, if any, from Good Laboratory Practice (GLP) standards with laboratory personnel. The CRO must then design a corrective action plan. The FDA must approve this plan in order for the CRO to retain its Good Laboratory Practice (GLP) designation. This inspection procedure ensures uniform quality and compliance with FDA guidelines, assuring clients that the testing, such as a ligand binding assay, performed in a Good Laboratory Practice (GLP) facility, will be done under the highest possible standards.

Why Every CRO is Not a Good Laboratory Practice GLP Facility

Because a contract research organization, such as Accelerō® Bioanalytics, gains stature and a reputation for reliability when it is Good Laboratory Practice (GLP) compliant, pharmaceutical firms that need ligand binding assay work and other essential laboratory studies will actively seek it out. Therefore, it makes sense that all CROs would strive for the Good Laboratory Practice (GLP) designation.

The truth, however, is that earning a Good Laboratory Practice (GLP) certification is a time-consuming, meticulous process that puts a CRO to greater expense than a non-Good Laboratory Practice (GLP) compliant facility. More highly specialized training and divisions of responsibility among the staff in a Good Laboratory Practice (GLP) means more expense. Safeguarding against cross-contamination, according to Good Laboratory Practice (GLP), when performing more than one ligand binding assay simultaneously means additional laboratory space is necessary, requiring a more expensive facility.

When a contract lab, such as Accelerō® Bioanalytics, is willing to invest the time and money it takes to comply with Good Laboratory Practice (GLP) guidelines, that means that the staff values those ideals set forth by the FDA to ensure that they provide only the most accurate and reproducible data from a ligand binding assay or other microRNA study to pharmaceutical development firms. While the difficulties presented by Good Laboratory Practice (GLP) compliance may prove too exhaustive for some CROs to overcome, Accelerō® Bioanalytics goes the extra mile on a daily basis to comply with Good Laboratory Practice (GLP) protocols.


Putting the Pieces Together:
Good Laboratory Practice GLP and the Ligand Binding Assay

The laboratory analysis of a ligand binding assay is only one aspect of the bioanalytical process governed by Good Laboratory Practice (GLP). The pre-assay collection of the biological sample to be used in the procedure, as well as the post-assay documentation that supports the ligand binding assay are equally important.

While sample collection and processing is often done in off-site facilities, making it impossible for the Good Laboratory Practice (GLP) contract research organization to ensure uniformity of ligand binding assay materials, adherence to Good Laboratory Practice (GLP) procedures by other entities carrying out the processing ensures the uniformity of the result.

Good Laboratory Practice (GLP) standard guide the labeling, documentation, and storage of samples once they reach the CRO. Good Laboratory Practice (GLP) also proscribes the detailed record keeping that tracks and catalogs all ligand binding assay materials, eliminating the possibility of mix-ups and safeguarding the integrity of the supplies.

Each area of the Good Laboratory Practice (GLP) facility will have an SOP that informs receipt and handling of test items and equipment. Guidelines for laboratory operations for the ligand binding assay procedure as well as regulations for documentation ensure that, from receiving the supplies to recording the results, technicians complete all aspects of the ligand binding assay according to Good Laboratory Practice (GLP) standards.

Accelerō® Bioanalytics is a Good Laboratory Practice (GLP) facility with the experience and standards to undertake any type of ligand binding assay on a contract basis, providing the high quality, reproducible results critical to the drug approval process.


Accelerō® is a registered trademark of Accelero Bioanalytics, Berlin.

More details on bioanalytical ligand binding assays in drug development are kindly presented in our ligand binding assay album.