Defining The Necessary Steps in Antibody Development

Antibodies may have made headlines during the pandemic, but they’ve long played an indispensable role in medical research and its applications. Today, therapeutic antibodies—specifically, monoclonal antibodies—are the

Monoclonal antibody development renders these medications and the clinical research behind them possible. It refers to the process in which antibodies are produced and characterised. 

This is performed by injecting an antigen (such as an allergen or bacteria) into a host animal to induce an immune response, which creates multiple antibodies that are screened and selected for use.

Therapeutic antibody development has huge implications. Not only does monoclonal antibody production shape pharmaceutical treatments for an extensive range of conditions (including autoimmune disorders,and cancer), but it also greatly influences our understanding of disease and diagnostics.

Put simply,of armour against pathogens and toxins. They’re characterised as “protective proteins” generated in the immune system in response to an antigen or anything it registers as foreign (such as a virus or toxin). Produced specifically by a B cell, theyto neutralise and eradicate them.

Human antibodies are broken down into five isotypes according to their location. In the realm of research, however, scientists frequently focus on two broader types of antibodies:

• Polyclonal antibodies, which are produced by multiple immune cells and bind to several different epitopes of a single antigen 

• Monoclonal antibodies,produced in a laboratory via tissue-culture techniques, and recognise a single epitope of an antigen

While both have value, monoclonal antibodies are noted for their precision and ability to target specific disease-causing antigens. They’re widely used in the treatment of certain conditions, including:

• Cardiovascular disease

• Lupus

• Cancer

• Rheumatoid arthritis

may vary by organisation, but it typically entails the following.

The type of antigen chosen to generate antibodies hinges on the type of disease or condition being targeted. Generally speaking, the most ideal antigen is one that most closely mimics the target molecule of antibody fragments that will be leveraged in the final treatment or application.

After selection, the antigen sample is prepared for safe injection into the host animal (or for ex vivo processes) by purifying or synthesising the antigen and conjugating it with a carrier protein.

The method used for immunisation depends on the characteristics of the antigen and the aim of the discovery project or treatment. 

A few of the most common include:

• Conventional immunisation, such as subcutaneous injections or intravenous injections

• In vitro immunisation, which is deemed one of the leading methods for finding fully human antibodies

• Transcutaneous immunisation is a novel technique in which the antigen is applied topically(or substances that intensify the immune response)

This step uses various technologies, including hybridoma creation—or the manufacturing of hybrid cells that will produce the antibodies.

As mentioned, the immune response is generated by B cells in the immune system. Successful antibody development relies on activating these cells' capacity to bind to the antigen.

Screening and selecting antibody candidates is a vital aspect of the process. At this stage, assays such as ELISA (or Enzyme-Linked Immunosorbent Assay) are employed to examine monoclonal cell lines and determine which are generating the desired antibodies.

for their:

• Antigen-binding abilities and developability, with high-affinity antibodies binding more quickly to antigens 

• Efficacy (particularly in terms of affinity maturation and effector function improvement)

• Safety and manufacturability

has evolved substantially since the technology to develop monoclonal antibodies was invented in the 1970s. Now, a host of advanced technologies are used to simplify and enrich the process, including:

• Hybridoma technology produces hybrid cells and bispecific antibodies that can bind to two antigens.

• Phage display is a technology commonly used in vitro selection to discover humanized antibodies (and to enhance antibody properties).

• Recombinant DNA technology facilitates the production of recombinant monoclonal antibodies that bear a stronger resemblance to those generated in humans.

Next-generation sequencing and high-throughput screening methods are also utilised in antibody development.

For the creation ofthe antibodies selected in the discovery process are then put through rigorous testing via

• Phase I (or monoclonal antibody pharmacokinetics) assesses the potential treatment’s safety, efficiency, and dose range in 10-20 healthy participants 

• Phase II examines the medication’s efficacy on a specific condition or disease in a larger pool of volunteers (usually 100-300)

• Phase III evaluates the drug’s safety and efficacy on hundreds (or even thousands) of patients (and, in some cases, over the course of several years)

If a medication passes the Phase III trial and exhibits the potential to receive regulatory approval, it will need to be produced at scale. This calls for optimising:

• Cell culture conditions

• Purification strategies

• Equipment

must also be implemented to ensure the product is consistent, effective, and meets the standards of Good Manufacturing Practices (GMP).

A therapeutic antibody drug must then receive regulatory approval, such as from the US Food and Drug Administration (FDA) or, in the UK, the Medicines and Healthcare Products Regulatory Agency (MHRA).

It’s important to note that antibody development and clinical development may require several years. Further, onlyof pharmaceutical drugs are approved, which enables them to enter Phase IV (a stage that provides additional insights into the drug’s long-term safety and value). However, those that do can be taken to market and potentially make a tremendous impact on the quality of life of many.

Roche has been at the forefront of antibody development since its start in the 1970s. Today, our renowned pharmaceutical company continues its legacy of leveragingfor the treatment of an array of conditions, including inflammatory diseases and cancer. 

Discover more about human monoclonal antibodies, antibody development, and how Roche is leading the way in healthcare innovation.