• Disease-modifying antirheumatic drugs (DMARDs) are approved to treat axial spondyloarthritis when nonsteroidal anti-inflammatory drugs (NSAIDs) are ineffective at managing symptoms.
• Conventional DMARDs suppress the immune system as a whole.
• Biologic DMARDs target specific aspects of the immune system involved in inflammation.

A range of conventional and biologic treatment options are available for axial spondyloarthritis, a type of inflammatory arthritis that affects the spine and can impact joints in other parts of the body. NSAIDs are recommended for initial first-line treatment. However, conventional and biologic DMARDs are often advised for active axial spondyloarthritis when symptoms persist despite the use of NSAIDS.

Sometimes called spondylitis or spondyloarthritis or axSpA, axial spondyloarthritis is an autoimmune condition in which the immune system is overactive and attacks healthy tissue. Types of axSpA include ankylosing spondylitis (also called AS or radiographic axSpA) and nonradiographic axSpA.

The condition is chronic and causes inflammation in joints and other organs. Symptoms of axSpA include debilitating back pain, pain in other joints, stiffness, and fatigue. Conventional and biologic DMARDs are approved to treat the underlying inflammation caused by disorders in the immune system.

What Are DMARDs?

DMARDs are medications approved to treat inflammatory arthritis. Conventional DMARDs — also known as conventional synthetic DMARDs — broadly suppress the entire immune system. Many conventional DMARDs are considered immunosuppressant drugs.

Biologic DMARDs target specific aspects of the immune system and block them from attacking healthy cells. Biologics are generally considered immunomodulators. However, methotrexate, which is a conventional DMARD, is sometimes considered an immunomodulator as well.

DMARDs are used to help reduce disease activity, slow disease progression. and prevent bone fusing and joint damage in people with spondylitis. Left untreated, axSpA can result in chronic pain and disability. Both conventional and biologic DMARDs can be highly effective in the treatment of axSpA and greatly improve quality of life for many people.

Conventional DMARDs

Methotrexate and sulfasalazine (sold as Azulfidine) are conventional DMARDS that may be recommended for the treatment of axSpA.

Methotrexate

Methotrexate may be prescribed alone or together with tumor necrosis factor (TNF) inhibitors — a type of biologic therapy. A doctor may prescribe this pairing when TNF therapy alone does not provide adequate relief and peripheral joints have persistent inflammation. Methotrexate can be self-injected or taken as a tablet orally.

Methotrexate causes cells to release adenosine, which helps reduce inflammation in people with various types of inflammatory arthritis, like axSpA, rheumatoid arthritis, and psoriatic arthritis. Common side effects include nausea, vomiting, mouth sores, and fatigue.

Sulfasalazine

Sulfasalazine may be prescribed for the treatment of spondylitis when peripheral joints — joints other than those connected to the spine — are affected. Sulfasalazine is sometimes recommended when TNF inhibitors — a type of biologic — are not appropriate for someone with axSpA.

Sulfasalazine is taken orally as a tablet. Common side effects include headache, nausea, indigestion, vomiting, and reversible male infertility. Sulfasalazine is a sulfa drug, a type of antibiotic to which some people are allergic.

Biological DMARDs

Biological DMARDs may be recommended for the treatment of axSpA when the disease remains active after conventional DMARD treatment has proven ineffective. Whereas most pharmaceuticals are made from chemical molecules, biologics are complex proteins made from living cells. Biologic drugs with names that end in “-mab” are monoclonal antibodies, which are derived from animal cells.

Biologic drugs are taken by subcutaneous injection (under the skin) or intravenous (IV) infusion because the large protein molecules cannot be absorbed well by the digestive system if taken orally.

Learn more about the differences between injections and infusions.

Types of Biologic DMARDs Used for Spondylitis

Each class of biologic drug is designed to interfere with a specific aspect of the immune system to prevent it from overreacting and causing inflammation and damage. Tumor necrosis factor is a target of several DMARDs. TNF is a signaling protein involved in chronic inflammation.

TNF-alpha inhibitors (also called TNF inhibitors or anti-TNF drugs) used in the treatment of axSpA include:

• Cimzia (certolizumab pegol)
• Enbrel (etanercept)
• Humira (adalimumab)
• Simponi (golimumab)
• Remicade (infliximab)

Interleukins (ILs) are another type of protein involved in inflammation, and they are also targets of some spondylitis treatments. IL inhibitors — designated by numbers — used to treat spondylitis include IL-17 inhibitors Cosentyx (secukinumab) and Taltz (ixekizumab), and Stelara (ustekinumab), an IL-12/23 inhibitor.

Side Effects from Biologic Drugs

Side effects and allergic reactions can occur with biologic drugs. People who take biologics have an increased risk of infection because these drugs suppress the immune system. Before you begin biologic treatment, you will receive blood tests to check for past exposure to hepatitis and tuberculosis infections. Blood work will also be monitored during treatment.

Common side effects include reactions at the injection site, such as redness, tenderness, itchiness, or rash. Allergic reactions can cause chills, shortness of breath, or itchy face.

Rare side effects can affect the nervous system and cause tingling or abnormalities with vision. Heart problems are another rare side effect. Any swelling of hands or ankles should be reported to your doctors immediately.

Your rheumatologist and health care providers will discuss side effects in detail with you. If you and your health care team determine that biologic treatment is appropriate for you, it is essential to let your doctors know about any side effects you experience.

Read more about what to expect when starting a biologic.

Talk With Others Who Understand

On MySpondylitisTeam, the social network for people with spondylitis and their loved ones, more than 76,000 members come together to ask questions, give advice, and share their stories with others who understand life with spondylitis.

Do you have questions about the differences between conventional DMARDs and biologic treatments? Share your experience in the comments below, or start a conversation by posting on your Activities page.