“Biologic agents have been used to treat rheumatoid arthritis since the late 1990s,” says Jonathan Kay, MD, a rheumatologist, endowed chair in rheumatology, and director of clinical research in the division of rheumatology at UMass Memorial Medical Center and the University of Massachusetts Medical School in Worcester. Today, biologics are used to treat ankylosing spondylitis as well. Most biologics for ankylosing spondylitis work by blocking or inhibiting TNF, a protein that plays an important role in triggering the inflammation that can cause your joints to be swollen and painful. Block the protein, and you stop the inflammatory process, Dr. Kay says. Five TNF inhibitors have been approved to treat ankylosing spondylitis:
AdalimumabCertolizumabEtanerceptInfliximabGolimumab
In addition, two biologics designed to block a different inflammation trigger called IL-17 have been approved:
IxekizumabSecukinumab
These drugs work by binding to IL-17, a protein that activates inflammation as part of your body’s normal immune response. People with ankylosing spondylitis may have higher-than-normal levels of IL-17, which can lead to excessive inflammation. “There’s some published evidence that in some people with ankylosing spondylitis, biologics can potentially slow the progression of structural change caused by the disease,” Kay says. The theory is that the biologics interfere with the underlying inflammatory process that causes structural damage and new bone formation, he says. “If NSAIDs are ineffective, treatment with a biologic is the appropriate next step,” Kay says. Biologics are useful for alleviating the back pain and stiffness of ankylosing spondylitis. They are believed to help reduce inflammatory back pain and improve physical function and reduce fatigue, allowing people with ankylosing spondylitis to have better quality of life. However, if the joints in your arms and legs are also affected by ankylosing spondylitis, a traditional DMARD, such as sulfasalazine or methotrexate, may be prescribed. “Different individuals respond slightly differently to each type of biologic,” Kay says. “If you don’t have success with one, you might with another.” You and your doctor should work together to find the one that’s best for you. Biologics for ankylosing spondylitis are given either by injection or intravenous infusion at a medical facility. “Some people prefer to sit in a facility while the medication is infused, whereas others prefer an injection because they can administer it themselves at their convenience,” Kay says. How frequently you’ll receive treatment depends on the specific biologic you’re taking.
Cautions About Biologics
As with any medication, biologics come with their own set of risks and side effects. The most common side effects include pain and irritation at the injection site. Because biologics affect your immune system, taking them puts you at increased risk for infections as well as for reactivation of tuberculosis (TB), Kay says. That’s why it’s important to be tested for TB before starting treatment with biologics. You should also take steps to reduce your risk of infections while taking biologics, such as staying up-to-date on vaccinations, washing your hands frequently, and avoiding people who are sick. Biologics can also be expensive. “The cost of these medications can be a barrier to their use for some people,” Kay says. “It can limit their ability to choose this treatment option for ankylosing spondylitis.” However, a number of the manufacturers of biologics have patient-assistance programs that provide help with costs and copayments. If cost is an issue for you, consider exploring these and other patient-assistance programs, as well as drug discount cards. If you’re not satisfied with your current ankylosing spondylitis treatment plan, talk with your doctor about making changes and whether biologic medication might be right for you.
