Stelara for Psoriasis and Psoriatic Arthritis

Stelara (ustekinumab) is an injected biologic drug approved by the U.S. Food and Drug Administration (FDA) for the treatment of moderate to severe plaque psoriasis or psoriatic arthritis in adults. It works by tempering the autoimmune-induced inflammation that causes skin cells to rapidly multiply and form psoriatic plaques and, with time, can also affect the joints, causing pain, stiffness, and a loss of the range of motion.

In September 2016, Stelara was also approved for the treatment of Crohn's disease.

Plaque psoriasis and psoriatic arthritis are both autoimmune disorders in which the immune system inexplicably attacks cells in the upper layer of skin (epidermis). Antibodies are what activate the immune response unnecessarily and release inflammatory substances, called cytokines, into the bloodstream. This leads to long-term inflammation that can be damaging to cells.

Stelara is a monoclonal antibody—a type of drug manufactured in the lab that is identical to immune cells called antibodies, which work to counteract this response.

Stelara works by suppressing two specific cytokines, called interleukin 12 (IL-12) and interleukin 12 (IL-23). Both play a key role in inflammatory diseases like psoriasis and psoriatic arthritis.

Stelara is intended for adults 18 and over who are unable to achieve control of moderate to severe plaque psoriasis with topical or oral medications.

Stelara can also be used with or without methotrexate for people with psoriatic arthritis. In severe cases (such as a rare complication known as arthritis mutilans), Stelara may be used in first-line combination therapy.

Stelara is administered as a subcutaneous (under the skin) injection. It is available in 45-mg and 90-mg single-use, prefilled syringes. It is also offered in 45-mg and 90-mg single-use vials.

The dose varies based on body weight as follows:

• For adults 220 pounds (100 kilograms) or less, the recommended dose is 45 milligrams (mg) initially and four weeks later, followed a 45-mg injection every 12 weeks.
• For adults over 220 pounds, the recommended dose is 90 mg initially and four weeks later, followed a 90-mg injection every 12 weeks.

As with any other drug, there are side effects associated with Stelara use. Many are the result of immune suppression, in which ongoing use may leave you vulnerable to certain infections.

The most common side effects (affecting at least 1% of users) include:

• Colds
• Upper respiratory infections
• Headaches
• Fatigue
• Diarrhea
• Dizziness
• Back pain
• Itchiness
• Muscle aches

Less commonly, Stelara can cause the reactivation of tuberculosis (TB). Prior to treatment, people should be tested for TB and treated if an infection is identified.

Allergic reactions, including anaphylaxis and angioedema, were not reported in any of the premarket studies but have since been seen in isolated cases. If this occurs, stop Stelara and call your doctor immediately.

If left untreated, anaphylaxis can lead to shock, coma, respiratory or heart failure, and death.

Stelara should not be used in people with a known hypersensitivity to ustekinumab or any of the drug's inactive ingredients. Anyone with a previous reaction should not be rechallenged no matter how mild the reaction may have been.

Stelara should be used with caution with other immune-suppressive drugs. The accumulative effect may leave you vulnerable to a wider range of serious infections. The drugs are not outright contraindicated for use with Stelara (and may, in fact, be beneficial when prescribed correctly), but they should be prescribed and carefully managed by the rheumatologist overseeing your care.

Among the medications of special concern:

• Cyclosporine
• Decadron (dexamethasone)
• Imuran (azathioprine)
• Medrol (methylprednisolone)
• Methotrexate
• Prednisone
• Prograf (tacrolimus)
• Rapamune (sirolimus)

Because your immune system is actively suppressed by Stelara, you will need to avoid certain live attenuated vaccines. These are vaccines made with deactivated but still living viruses. If used, the vaccine may actually instigate the disease it was meant to prevent.

The vaccines you need to avoid without exception include:

• Adenovirus types 4 and 7, live (oral)
• Herpes zoster vaccine, live
• Influenza virus vaccine quadrivalent, live
• Influenza virus vaccine trivalent, live
• Measles (rubeola) vaccine
• Measles, mumps, and rubella (MMR) vaccine, live
• Poliovirus vaccine, live (oral)
• Rotavirus vaccine, live (oral)
• Rubella vaccine
• Smallpox vaccine, live
• Varicella-zoster vaccine, live
• Yellow fever vaccine

Moreover, people should not receive the Bacille Calmette-Guerin (BCG) vaccine, used to prevent TB, one year prior to treatment or for one year after Stelara has been stopped.

Stelara should not be used if you have an active infection of any sort, as it suppresses the immune response and makes it harder for the body to fight back. According to premarket research issued by the FDA, serious infections occurred in 0.9% of Stelara users as a result of the drug's immunosuppressive effects.

Stelara may also increase the risk of certain cancers, most especially squamous cell skin cancer. With that being said, it doesn't appear to "cause" cancer but rather promote the development of the disease in people with pre-existing risk factors. Anyone treated with Stelara should be monitored for non-melanoma skin malignancies.

There have yet to be any well-controlled studies investigating the use of Stelara during pregnancy. The drug is currently classified as Pregnancy Category B, meaning that animal studies have not shown any evidence of fetal harm.