Around 10 to 30 percent of people who have psoriasis, a disease characterized by red and scaly patches of skin, will also develop psoriatic arthritis. Psoriatic arthritis causes joint pain, swelling, and stiffness, and it can have long term effects if not caught and treated early. If you have psoriatic arthritis, don’t panic. Our understanding of the disease has come a long way in recent years, and as a result, many advances have been made in its treatment. Understanding Psoriatic Arthritis Your immune system is designed to protect you. Normally when your body senses something harmful, like a virus, it uses special proteins called cytokines to start the process of inflammation within your immune system. Inflammation increases blood flow and brings immune cells to the area of the “intruder” to try and get rid of it. Psoriasis and psoriatic arthritis are autoimmune diseases. This means your immune system becomes overactive and attacks its own healthy tissues by mistake. In psoriatic arthritis, this incorrect immune response leads to inflammation in your joints, causing the pain and swelling you feel. This knowledge has been pivotal in developing treatments for psoriatic arthritis. Slowing down the immune response decreases inflammation, thereby lessening the unpleasant symptoms. A class of medications known as disease modifying antirheumatic drugs (DMARDs) was the first used to treat psoriatic arthritis because of its action in suppressing the immune system. Some examples of DMARDs include cyclosporine (Sandimmune), methrotrexate (Trexall), sulfasalazine (Azulfidine, and leflunomide (Arava). Biologics: Advancing Psoriatic Arthritis Treatment to the Next Level The use of biologics, a type of drug made from living organisms, has revolutionized the treatment of psoriatic arthritis (and many other diseases too). They may be used for moderate to severe cases or if DMARDs aren’t effective in treating the disease. Researchers have been able to identify specific proteins that are involved in the inflammatory process causing psoriatic arthritis and develop biologic drugs that block those proteins. This can stop the inflammation that triggers arthritis symptoms. There are a few different classes of biologics that are currently approved, each blocking, or “inhibiting,” a specific protein or cell: Tumor necrosis factor alpha (TNF-alpha) inhibitors: These were the first biologics for psoriatic arthritis and have been widely used. This includes adalimumab (Humira), certolizumab (Cimzia), etanercept (Enbrel), golimumab (Simponi), and infliximab (Remicade). Interleukin 17 (IL-17) inhibitors: Secukinumab (Cosentyx) and the recently approved ixekizumab (Talz) are administered by injection. They have been shown to provide improvement in joint symptoms and mobility, as well as help clear the skin. Interleukins 12 and 23 (IL-12/23) inhibitors: The dosing schedule for Ustekinumab (Stelara) is convenient. After two initial injections, it only needs to be given every 3 months. T-cell inhibitor: Rather than block a specific protein, Abatacept (Orencia) blocks T-cells, a type of white blood cell involved in inflammation, from activating. It may be given as an injection or as an infusion into your vein. The most common side effects of biologics include upper respiratory infection, nausea, and diarrhea. Since they affect the immune system, there is an increased risk of serious infections, such as tuberculosis. Oral Psoriatic Arthritis Treatments Another way to treat psoriatic arthritis comes in the form of a pill. These oral medications target specific enzymes inside the immune cells. This slows down the inflammatory response and improves joint swelling and tenderness. Two types are currently available: Phosophodiesterase 4 (PDE4) inhibitor: Apremilast (Otezla) blocks an enzyme, PDE4, that plays a role in inflammation. Diarrhea, headache, and nausea were the most common side effects. Your doctor should monitor you for signs of depression or weight loss while taking this medication. Janus kinase (JAK) inhibitor: Tofacitinib (Xeljanz) is a new biologic that stops the action of the janus kinase enzyme. This pill may be taken once or twice daily. Side effects include headache, diarrhea, and upper respiratory infection. Most people with psoriatic arthritis will find their treatments need to be adjusted over time. You may learn that you cannot tolerate a particular drug or one treatment that used to work well suddenly loses its effectiveness. Luckily, your doctor now has a larger arsenal of drugs to choose from, so if you are still struggling with pain and stiffness, reach out to your doctor. There may be other treatments available to bring you the relief you seek.