Biologics for Ankylosing Spondylitis: Are They Right for You?

The biologics approved by the U.S. Food and Drug Administration for AS include eight original, or reference, drugs as well as biosimilars, which are medications that closely resemble the originals but are typically less expensive.

TNF-Alpha Inhibitors

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

IL-17 Inhibitors

• bimekizumab-bkzx (Bimzelx)
• ixekizumab (Taltz)
• secukinumab (Cosentyx)

Biologics for AS aren’t available in pill form. They must be administered either through an intravenous (IV) infusion at a medical office or clinic or as an injection you can give yourself at home.

“Biologics are a special class of medications that are made using live cultures that generate large proteins with the ability to suppress the immune system — called antibodies. Our gut cannot absorb the antibody as a whole and would break it apart. This is why we need to inject it into the lower tummy or the upper thigh to bypass the gastrointestinal tract,” says Ayad Alkhatib, MD, a rheumatologist and senior staff physician at Henry Ford Health in Michigan.

“Most biologics are administered using auto-injectors,” adds Jonathan Kay, MD, the Timothy S. and Elaine L. Peterson Chair in Rheumatology at the UMass Chan Medical School in Worcester, Massachusetts. “They use very small-gauge needles, which hardly hurt and don’t cause significant discomfort.”

How often you’ll need to take a biologic varies. “Drugs such as adalimumab are typically administered every other week, etanercept is administered weekly, golimumab is administered monthly, certolizumab pegol is administered every other week, and ixekizumab and secukinumab are administered monthly,” says Dr. Kay.

Your symptoms may begin to improve within a few weeks after starting a biologic, or it may take a couple months to notice a difference. Your symptoms may continue to improve for months afterward.

By reducing inflammation in your body, biologics may help reduce your risk of developing health conditions related to AS, such as uveitis (eye inflammation), inflammatory bowel disease, and cardiovascular disease.

You may notice that a biologic works less well after you’ve taken it for months or years. This may be because your immune system can develop antibodies that bind to the particular medication, reducing its effectiveness. If this happens, your AS symptoms may start to come back. If a biologic no longer works for you, switching to a different one might do the trick.

As with any medication, biologics come with potential risks and side effects. The most common are pain and swelling at the injection site. Skin reactions are generally mild and go away on their own, but if you experience symptoms such as shortness of breath, dizziness, or fever, call your doctor or seek emergency care, since these could be signs of an allergic reaction to the medication.

Because biologics suppress your immune system, they also increase your risk of bacterial and fungal infections. What’s more, they may activate latent (inactive) infections, including tuberculosis and viral hepatitis (like hepatitis B), so you will need to be tested for these before starting a biologic. If you develop an infection while taking a biologic, it’s important to tell your doctor immediately so you can be treated.

The eight original biologics can be expensive, costing tens of thousands of dollars per year or even more. Biosimilars tend to be much cheaper but are still pricey for many people. Most insurance companies will cover at least part of this cost, but how much and what you’ll need to pay out of pocket depends on your insurance plan.

How you take the drug may also affect whether insurance covers it. “Medicare covers hospital-administered intravenous medications,” says Kay. “So someone who’s on Medicare who needs a TNF inhibitor might benefit from, say, infliximab infusions, since they’re covered by insurance in a way that is different from outpatient-administered, self-administered injectables.”

If you’re concerned about paying for your medication, talk to your doctor, who can work with you to determine the best biologic for your insurance coverage and treatment needs. Your healthcare team can also discuss financial assistance — state programs, pharmacy discount programs, and prescription assistance programs through the drug manufacturers — that can help you get your medication for less money or even no cost.