How Do Biologics Work? A Behind-the-Scenes Look into Humira, Aimovig, and More

Biologic medications represent the cutting edge of scientific technology. They’re complicated medications that come from living sources, such as bacteria, animals, and even other people. Biologics are often made in large tanks called bioreactors, and they come in the form of vaccines, monoclonal antibodies (lab-made proteins), growth factors, and more.

Biologics treat health conditions ranging from Alzheimer's disease and migraines to ulcerative colitis and lung cancer. Some biologics also treat rare conditions that you may not have heard of, such as polymyalgia rheumatica. You may currently use a biologic or have seen news stories about them, such as with insulin glargine (Lantus, Basaglar, Toujeo).

Biologics are versatile. This is largely because they function in different ways. Let’s explore how biologics work in your body and answer a few questions you may have about starting a biologic.

How do biologics work?

A “biologic” refers to a few things. It’s a catchall or umbrella term. Many different biologics are available, and they work in a seemingly endless number of ways. The list of FDA-approved biologics grows every year.

For instance, you may be familiar with insulin. It’s a hormone that manages blood glucose (sugar) in the body. A lack of insulin — or a poor response to insulin — can lead to diabetes. Lab-made insulin is available as a biologic medication that you can inject to replace natural insulin.

Rheumatoid arthritis and ulcerative colitis are autoimmune conditions that prompt your immune system to mistakenly attack your joints and colon, respectively. Autoimmune biologics make a positive difference by reducing inflammation and calming immune system overactivity. 

EXPERT PICKS: WHAT TO READ NEXT

• Biologics vs. small molecules: Explore how biologics and small molecule drugs are different from each other.

• The world of biosimilars: Understand what biosimilars are and how they differ from reference (“brand name”) biologics.

• Biosimilar cost savings: Learn how biosimilars can help lower your medication costs.

Biologics have anticancer uses too. They help boost your immune system to help it fight certain types of cancer.

The list goes on. If you’re curious about how your specific prescription works, your pharmacist can break it down for you.

Examples of biologic uses

Biologics treat a wide variety of conditions. This includes, but isn’t limited to:

• Alzheimer’s disease

• Diabetes

• Rheumatoid arthritis

• Ulcerative colitis

• Crohn’s disease 

• Multiple sclerosis

• Hemophilia

• Migraine

• Lung cancer

• Lymphoma

• Colorectal cancer

Examples of biologic medications

Humira (adalimumab), Aimovig (erenumab), and Roctavian (valoctocogene roxaparvovec-rvox) are three examples of biologic medications.

Humira is a biologic medication that treats many autoimmune conditions, such as rheumatoid arthritis, uveitis, and psoriasis. It works by blocking tumor necrosis factor proteins to quell inflammation. You can self-administer Humira under the skin.

Aimovig is a medication that helps prevent migraines. It works by blocking the activity of a molecule called calcitonin gene-related peptide (CGRP). CGRP is associated with migraine pain and inflammation. Aimovig is also available as an injection that you administer under the skin.

Roctavian is a gene therapy medication that treats hemophilia A, a condition where blood doesn’t clot normally. It works by inserting a functioning copy of a gene into your body to restore normal blood clotting. You’ll receive Roctavian as a one-time infusion into your vein.

How do biologics differ from biosimilars?

Broadly speaking, biologic medications can be separated into two categories: reference products and biosimilars.

• Reference product: This is an original biologic that’s newly developed by a drug company. It’s comparable to a brand-name medication.

• Biosimilar: This is a biologic that’s highly similar in structure and function to a reference biologic. Some people casually refer to biosimilars as “generic” versions of a reference product.

There aren’t any meaningful safety or effectiveness differences between biosimilars and reference biologics.

However, some biosimilars are further categorized as interchangeable biosimilars. They’re not any “better” than standard biosimilars. But they do have extra supporting data to show people can switch back and forth between them and a reference product without having issues.

How are biologics manufactured?

Biologics are produced through an intricate manufacturing process. The end goal of making many biologics is to isolate antibodies so they can be transformed into your medication. The process can be broken down into three main steps.

Good to know: In contrast to biologics, small molecule drugs are much simpler to make. They are typically made using chemicals, not living cells or organisms. They don’t require bioreactors, either.

1. Cell selection

Scientists must carefully choose cells to use in the biologic manufacturing process. These are often animal or plant cells. The right cells need to be able to produce the proteins in your medication. At the same time, scientists need to avoid cells that can cause unintended side effects.

Scientists “engineer” these cells to produce the proteins that are found in your biologic medication.

2. Cell growth

A few cells aren’t enough to get the job done. Scientists take their chosen cells and multiply them several times over to make a much larger batch in bioreactor tanks. It’s a sensitive process that requires monitoring and adjusting temperature, acidity, and more. This process is done in order to produce doses in bulk for people all over the world.

You can compare this process to baking a double batch of cookies. You want just the correct amount of sugar, salt, and dough in the right conditions (heat and consistency) for your cookies to come out just right.

3. Purification

At this point, the bioreactor tanks now contain an ample quantity of a biologic. But there’s one step to go. The tanks still contain extra materials that you don’t want in your medication. Scientists remove unwanted proteins, cells, and other impurities in a process called purification. 

A biologic is ready to use once it’s purified and packaged into its intended dosage form.

Is it possible to make an oral biologic?

Maybe in the future. Currently, though, no oral biologics are available for use. 

This is because biologics are sensitive. They can’t survive in harsh environments, like your gut. The digestive system is designed to break down proteins into smaller parts called peptides and amino acids. This disassembly renders biologics ineffective.

That being said, medication manufacturers are actively exploring how to make oral biologics. They’re looking for ways to stabilize them so they can survive in your digestive system. One possibility is by using nanotechnology.

Biologic side effects and risks

Biologic side effects vary from one medication to the next. This is because they don’t all work the same way. However, some side effects happen because of how you’ll receive your biologic. Biologics are typically injected under-the-skin or infused into a vein (IV). 

If you’re prescribed an under-the-skin (subcutaneous) biologic, you may experience injection site reactions where the medication is administered. These local side effects include:

• Pain

• Redness

• Itching

• Bruising

• Swelling

• Minor bleeding

What’s more, you may experience infusion-related reactions if you’re receiving an IV biologic. Possible symptoms include:

• Rash

• Itching

• Flushing

• Fever 

• Low blood pressure

Some biologics carry a larger risk for infusion-related reactions than others. A healthcare professional may give you medications shortly before your infusion to lessen the severity of side effects that may appear. This includes medications such as Tylenol (acetaminophen), Benadryl (diphenhydramine), and steroids like prednisone.

Do biologics suppress the immune system?

Not always. This is typically only the case with biologics that treat health conditions related to excess inflammation.

The main example of this is with biologics that treat autoimmune conditions. They aim to calm down parts of your immune system to lessen inflammation. In turn, however, they can suppress your immune system as an unintended side effect.

Many biologics are an exception to this. Insulin and Hemlibra (emicizumab) are two biologics that don’t suppress your immune system. Insulin helps your body use and absorb glucose. Hemlibra works by helping your blood clot normally. Neither of these medications affect your immune system.

There’s another layer, too. Some biologics can actually have beneficial effects on your immune system. Keytruda (pembrolizumab) and other cancer biologics help optimize your immune system so it can fight cancer more effectively.

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Written by:

Mandeep Sohal, PharmD

Mandeep Sohal, PharmD, has more than 7 years of experience in the pharmaceutical industry and is licensed in California. In his career, he’s had experience with specialty pharmacy, community pharmacy, pharmacy benefit management, and pharmaceutical manufacturers.

Edited by:

Joshua Murdock, PharmD, BCBBS

Joshua Murdock, PharmD, BCBBS, is a licensed pharmacist in Arizona, Colorado, and Rhode Island. He has worked in the pharmacy industry for more than 10 years and currently serves as a pharmacy editor for GoodRx.

Reviewed by:

Stacia Woodcock, PharmD

Stacia Woodcock, PharmD, is a pharmacy editor for GoodRx. She earned her Doctor of Pharmacy degree from the University of Kentucky and is licensed in New York and Massachusetts.

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