The Specialist: Biologics for Psoriatic Arthritis

Biologics are immune treatments that are given by injection or infusion. They contain proteins that target a specific cytokine or protein in the blood and immune system that is involved in inflammation.

Disease-modifying antirheumatic drugs or DMARDs, in short, are used to treat psoriatic arthritis and other conditions including:

• rheumatoid arthritis
• axial spondyloarthritis
• psoriasis
• inflammatory bowel disease

Biologic DMARDs come from an animal or human source.

Synthetic DMARDs can work in a similar way but are made in a lab.

For psoriatic arthritis (PsA), biologic treatments include:

• TNF inhibitors:
  • adalimumab (Humira)
  • certolizumab pegol (Cimzia)
  • etanercept (Enbrel)
  • golimumab (Simponi)
  • infliximab (Remicade)
• IL-17 inhibitors:
  • ixekizumab (Taltz)
  • secukinumab (Cosentyx)
• IL-23 inhibitors:
  • guselkumab (Tremfya)
  • risankizumab (Skyrizi)
• IL 12/23 inhibitors:
  • ustekinumab (Stelara)

These treatments have different delivery methods, including:

• Self-injectable pens. These allow you to inject the drug into your skin. They have an auto-injector that makes the process easier.
• Pre-filled syringes. They contain a prepared dose, but the needle is plunged into the body manually. These devices help avoid contamination risk and errors in dosing.
• Infusions. These are delivered intravenously in a hospital or clinic setting, or at home.

Some biologics are more immunosuppressive than others, depending on which cytokine they are targeting and blocking.

In general, because biologics suppress the immune system, they increase the risk of common infections such as:

• upper respiratory infections
• pneumonia
• urinary tract infections
• skin infections

Antibiotics and vaccines can help reduce the risk while taking biologics for some infections, like pneumonia.

Injection site reaction is a skin reaction at the location where the shot is injected and might include:

• redness
• itching
• swelling
• pain

This is not an allergy and should resolve on its own.

An infusion reaction can show as:

• redness at the infusion site
• flushing
• nausea
• rash
• shortness of breath
• chest tightness
• face swelling
• fever or chills
• high or low blood pressure

Patients are usually premedicated to prevent these complications and are monitored closely during their infusions.

TNF inhibitors can reactivate infections such as tuberculosis or hepatitis B. Patients are screened for these conditions before starting treatment.

They can also cause a rare lupus-like syndrome, can worsen congestive heart failure, and can cause liver problems with yellowing of the skin and eyes.

In some cases, TNF inhibitors can cause paradoxical psoriasis in people being treated for other conditions.

Biologics might slightly increase risks for certain cancers and progressive multifocal leukoencephalopathy and other demyelinating disorders.

The IL-17 inhibitors such as cosentyx have a risk of inducing inflammatory bowel disease such as Crohn’s Disease or ulcerative colitis.

Biologics are injected into the skin or infused into a vein. The specific dosage depends on the disease, so there are different regimens for the same drug.

For example, adalimumab (Humira) is prescribed as one injection every 2 weeks for PsA but requires a loading dose of weekly injection for psoriatic skin clearance. Humira is also used for inflammatory bowel disease.

Certolizumab pegol (Cimzia) is another TNF inhibitor that is injected as a loading dose every 2 weeks, three times in the first month, and then is followed by monthly maintenance doses.

Using the autopen

Each medication will have detailed instructions and videos on how to use. In brief, the steps are:

1. Take the autopen out of the fridge 30 to 90 minutes before you’ll use it. Leave it in the carton.
2. Lay out an alcohol swab, sharps container, and cotton ball or gauze with your autopen.
3. Pick a site for injection. The front of the thigh or stomach is good, but you shouldn’t go closer than 2 inches toward the belly button or too close to a previous injection site.
4. Wash your hands then clean the injection site with the alcohol swab.
5. Pull the cap off the autopen, looking to see that the medication is clear or yellow, which indicates it’s good to use. If it’s cloudy or has large flakes, you should not use it.
6. Squeeze the injection site with your fingers so it creates a raised platform. Holding the pen with your other hand, place it down firmly at a 90-degree angle on the skin.
7. Press the activation button to inject the medication and hold. You’ll hear a click when it starts to dispense and a second click after about 15 seconds when it’s complete. There may also be an indicator window that shows you it’s complete.
8. Pull the pen out of the skin and cover the injection site with a cotton ball or gauze.
9. Dispose of the pen in a safe container.

Using a pre-filled syringe

The steps for using a pre-filled syringe are largely similar to those for an autopen. Check the exact instructions for your medication online.

1. Take the syringe out of the fridge 15 to 30 minutes before you’ll use it. Leave on the needle cover.
2. Lay out an alcohol swab, sharps container, and cotton ball or gauze with your syringe.
3. Pick a site for injection. The front of the thigh or stomach is good, but you shouldn’t go closer than 2 inches toward the belly button or too close to a previous injection site.
4. Wash your hands then clean the injection site with the alcohol swab.
5. Hold the needle in one hand. Gently lift off the needle cover with the other hand. Don’t touch the needle!
6. Look to see that the medication is clear or yellow, which indicates it’s good to use. If it’s cloudy or has large flakes, you should not use it.
7. Hold the body of the syringe with your thumb and index fingers. Squeeze the injection site with your other hand to make a raised platform.
8. Dart the needle in at a 45-degree angle and push the plunger in until all the medication is dispensed.
9. Slowly remove the needle from the skin, keeping it at that 45-degree angle. Cover the injection site with a cotton ball or gauze.
10. Dispose of the syringe in a safe container.

You can take biologics in combination with synthetic DMARDs such as:

• methotrexate
• leflunomide
• otezla (a PDE4 inhibitor)

Certain biologics such as IL-23 and IL-17s can be used in combination with targeted small molecules such as Janus Kinase inhibitors while monitoring for immunosuppression. These biologics are not as immunosuppressive as TNF inhibitors and have a better safety profile.

NSAIDs and steroids can be used for symptom relief until the biologic is able to accumulate and be effective or during flares for symptom improvement.

Dr. Stella Bard is a board certified rheumatologist with over 13 years of experience in managing complex medical problems. She is a graduate of SUNY Downstate College of Medicine and completed her fellowship in UMDNJ Robert Wood Johnson. While there, she studied under world authorities in gout, Lyme disease, and scleroderma. She then set up a center dedicated to treating New York City residents living with rheumatologic conditions. As a long-time resident of the City, Dr. Bard is attuned to special health needs in its diverse communities. She serves as a medical advisor for Healthline.