“What biologics are everyone on? What works for you? How long did it take to work?” — a question from a myHSteam member.

If you have moderate to severe hidradenitis suppurativa (HS), your dermatologist may recommend trying biologics — injected medications — especially if other treatments, like antibiotics, topicals, or retinoids haven’t worked.

Biologic drugs are made from living organisms. These drugs treat HS by targeting specific parts of the immune system, which helps control inflammation.

In this article, we’ll discuss the use of biologics for treating HS.

What Is Hidradenitis Suppurativa?

HS, also known as acne inversa, is an inflammatory skin disease that causes painful bumps under the skin. These often form in areas where skin rubs together, such as the groin, armpits, breasts, and buttocks. People with HS can develop pus-filled abscesses, sinus tracts (tunnels under the skin), and scarring.

While the exact cause of HS is unknown, it is thought to be caused by blocked hair follicles and chronic (long-term) inflammation. Many people with HS have higher levels of inflammatory markers known as cytokines, which biologics can help control.

How Do Biologics Work?

To understand how biologics are used to treat HS, it is important to know more about the immune system, inflammation, and a class of biologics known as monoclonal antibodies.

Antibodies are proteins that are vital to the immune system. They are produced by specialized immune cells, known as B cells, to fight bacterial or viral infections. The human body can make almost 100 billion different types of antibodies. Each B cell produces only one type of antibody. Each antibody is a protein that recognizes and interacts with a specific target, known as an antigen.

Scientists can modify B cells in a lab to create monoclonal antibodies — specific antibodies that attach to a target protein — custom-made antibodies that target specific proteins linked to disease (like HS).

Because these antibodies come from a single B cell, all copies are identical. Researchers have designed monoclonal antibodies to target harmful proteins involved in the immune response, cancer, and other diseases.

Biologics for Hidradenitis Suppurativa

There are currently three biologics approved by the U.S. Food and Drug Administration (FDA) to treat HS. They are:

• Adalimumab (Humira) — Blocks tumor necrosis factor-alpha (TNF-alpha), a protein involved in inflammation
• Secukinumab (Cosentyx) — Blocks interleukin (IL)-17A, a chemical messenger involved in inflammation in many chronic diseases
• Bimekizumab-bkzx (Bimzelx) — The newest FDA-approved biologic for HS, which targets both interleukin (IL)-17A and interleukin (IL)-17F

Other biologics may sometimes be prescribed off-label to treat HS.

When Is the Right Time To Consider Biologic Treatment?

Biologics are usually recommended for moderate to severe HS or when other treatments haven’t worked. Your dermatologist will discuss your treatment options and help you decide if biologics are right for you.

What Are Biosimilars?

In some cases, you may be prescribed a “biosimilar” rather than a biologic. Biosimilars are drugs that are nearly identical to, but not exact copies of, original brand-name biologic medicines. For example, there are many biosimilars available for adalimumab.

Biosimilars undergo strict testing to make sure they work just as safely and effectively as the original biologic drug. Biosimilars are also usually cheaper than biologics.

What Is Being Researched?

Several clinical trials are studying both new and existing biologics for treating HS. This important research brings hope for the development of new treatments or the repurposing of already-existing drugs used for treating other health conditions.

This work means that additional HS treatments may become available in the future to people living with HS.

What To Expect When Starting Biologics

All biologics are given as injections or infusions. These may be given under the skin (subcutaneous), into muscle (intramuscular), or as intravenous (into a vein) infusions. Biologics cannot be taken by mouth because the digestive system would break them down, preventing them from being properly absorbed into the bloodstream.

The idea of injecting biologics can be overwhelming for some people. Many people find it gets easier with time, and your healthcare team can provide helpful tips to make the process more comfortable. It’s also important to know that, to remain effective, most biologics require special storage conditions when traveling.

Before starting biologic therapy, your doctor will likely perform some screening tests to make sure you are not at risk from any underlying conditions. These tests typically check for tuberculosis and hepatitis B. You may be monitored for these or other conditions during treatment to make sure you’re not at risk of developing complications.

Side Effects of Biologics

Most people find that the benefits of biologic treatment outweigh the possible side effects. The overall goal of treatment is to help you feel better and improve your quality of life. If you notice side effects, talk to your doctor about how to manage them effectively and whether they may fade over time.

Common side effects associated with biologic drugs include:

• Discoloration, pain, swelling, and itching at the injection site
• Increased risk for infections (because the drugs work by suppressing the immune system)
• Injection or infusion reactions, similar to allergic reactions (such as rash, chills, and flushing)

Always listen to your body. If you experience any of these new symptoms after using biologic drugs, contact your doctor right away:

• Painful rash or sores
• Chills
• Chest pain
• Numbness or tingling
• Shortness of breath
• Swelling
• Joint pain
• Vision problems

The symptoms listed above could signal an infection or a more serious condition. If you experience any of these symptoms, contact your healthcare provider immediately.

Talk With Others Who Understand

On myHSteam, more than 56,000 members come together to ask questions, offer support and advice, and share their stories with others who understand life with hidradenitis suppurativa.

Are you taking any biologic medications to treat your HS? Share your experience in the comments below, or start a conversation by posting on your Activities page.