Enbrel
What is Enbrel?
Enbrel (also known by its generic name etanercept) is a biologic medication approved in April 2004 by the U.S. Food and Drug Administration (FDA) for the treatment of moderate to severe plaque psoriasis and in January 2002 for the treatment of psoriatic arthritis. It is also approved for treating rheumatoid arthritis, juvenile rheumatoid arthritis and ankylosing spondylitis (arthritis affecting the spine). For more information about biologics as a class of treatment, please see the biologics section.
Key features
- FDA-approved for treating psoriasis and psoriatic arthritis
- Patients give themselves an injection under the skin once or twice per week
- Taken continuously to maintain results
- May reduce the progression of joint damage
- Long-term side effects still being evaluated
How does it work?
Enbrel blocks tumor necrosis factor-alpha (TNF-alpha), a chemical "messenger" in the immune system that signals other cells to cause inflammation. There is too much TNF-alpha in the skin of people with psoriasis and the joints of people with certain types of arthritis.
TNF-alpha can also lead to increased immune system activity through the activation of T cells. T cells are a type of white blood cell in the body; in psoriasis, once T cells are mistakenly activated, they can trigger inflammation and other immune responses and fuel the development of psoriasis lesions.
Enbrel helps lower the amount of TNF-alpha, thus interrupting the inflammatory cycle of psoriasis and psoriatic arthritis and leading to improvement in symptoms for many people who take it.
Who is a candidate?
Enbrel is prescribed for adults with moderate to severe plaque psoriasis who are candidates for phototherapy or other systemic (oral or injected) treatments. It is also prescribed for people with active psoriatic arthritis; it can help stop or slow the damage to joints caused by the disease.
Although Enbrel is approved for use in children as young as 4 for juvenile rheumatoid arthritis, it is not approved for treating psoriasis or psoriatic arthritis in children. Amgen, Enbrel's manufacturer, has filed for FDA approval for treating psoriasis in children.
Who should not take Enbrel?
- People with active serious infections or a history of recurrent infections
- People with a history of heart failure
- People with multiple sclerosis or other types of demyelinating neurologic diseases
Caution is advised for the elderly, due to the already increased risk of infection for this age group.
The impact of Enbrel on pregnant women or developing fetuses is not known, nor is it known if
the medication passes into breast milk in nursing women. Enbrel should only be given to pregnant or nursing women if there is a clear medical need, and if this decision is reached by a patient and doctor together. Pregnant women using Enbrel should talk to their doctor about enrolling in a pregnancy registry.
How is it used?
Patients take Enbrel at home by giving themselves an injection under the skin, similar to diabetes patients who give themselves insulin injections. The recommended dose for patients with plaque psoriasis is 50 mg twice weekly for three months, followed by a maintenance dose of 50 mg once weekly thereafter. The recommended dose for adult patients with psoriatic arthritis is 50 mg per week.
For psoriatic arthritis, the medication can be prescribed by itself or as a combination treatment with methotrexate, a systemic medication. In clinical studies, people taking Enbrel in combination with methotrexate for rheumatoid arthritis experienced more disease improvement than patients taking Enbrel or methotrexate alone. It is also safe to take Enbrel with pain relievers, such as nonsteroidal anti-inflammatory drugs (NSAIDs), that are often taken for arthritis.
Enbrel is designed to be taken continuously to maintain improvement. Arthritis symptoms generally return within a month after the medication is stopped. In the psoriasis studies, the symptoms generally returned within two months after Enbrel treatment was stopped.
What are the side effects?
Enbrel has been on the market since 1998 and has been used by hundreds of thousands of patients.
Therefore, more is generally known about its safety and its short- and long-term side effects than is known about some of the newer biologic medications. It should be noted that the majority of this knowledge is based on studies in patients with rheumatoid arthritis.
In the psoriasis and the arthritis studies, the most common side effects reported were:
- dizziness
- sore throat
- cough
- stomach pain
- injection site reactions (redness, itching, pain, swelling)
- upper respiratory infections
- headache
- rhinitis (irritation of the nose)
These side effects were generally mild and did not cause most patients to stop taking Enbrel. These events happened most often after the first dose of Enbrel and may decrease after additional doses.
Injection site reactions occurred in more than one out of three patients in the studies testing Enbrel for arthritis, but they were less frequent in the psoriasis studies (in less than one out of five patients). It is not known why. The reactions generally happened less frequently after the first month of treatment for all patients.
Serious infections, including some fatalities, have been reported with the use of Enbrel. The infections often occurred in patients using other medications that suppress the immune system. Serious infections are rare in patients taking Enbrel alone. Also, rare cases of tuberculosis have been observed in patients taking Enbrel.
Patients should be evaluated for latent (hidden) tuberculosis (TB) infections by getting a TB skin test prior to treatment with Enbrel. Doctors may also order a chest X-ray before starting treatment. Hidden TB must be treated first, before people can begin taking Enbrel.
The medication should not be started in someone with an active infection, and it may not be
recommended for someone with a history of recurring infections. If a serious infection develops, a doctor will most likely stop Enbrel treatment.
Rare cases of multiple sclerosis and other central nervous system disorders have been observed in association with Enbrel and medications that target TNF-alpha, although the connection between the disorders and the medications remains unclear. Due to rare reports of blood disorders, people taking Enbrel are advised to contact their doctor if they experience persistent fever, bruising, bleeding or paleness.
There have been reports of the worsening of congestive heart failure in a small number of patients taking Enbrel, as well as rare reports of new cases of congestive heart failure. Doctors are advised to use caution in prescribing Enbrel for patients with heart failure and to monitor them carefully.
The FDA has reviewed the association between TNF-alpha medications such as Enbrel and an increased risk of developing lymphoma, a type of cancer. The FDA concluded there is not enough data to know if these medications contributed to higher risk.
Enbrel's safety and side effects continue to be monitored by Amgen, Enbrel's manufacturer, and
the FDA.
For detailed information on side effects and safety, talk to your doctor.
How do I get Enbrel?
Enbrel is available by prescription, primarily from rheumatologists and dermatologists. Once a person makes the decision with his or her doctor that Enbrel is an appropriate treatment, a determination of insurance coverage will need to be made, and preauthorization from the insurance company will likely be needed.
Amgen has a special program where patients and doctors can get help with insurance questions
and other issues. For more information, call 888.4ENBREL (888.436.2735) or visit www.enbrel.com.
How much does it cost?
In general, biologics tend to be expensive; the cost of each drug can vary between $10,000 and $25,000 per year (or more), based on the dosage and treatment regimen prescribed by your doctor. Most insurance companies cover this medication for its approved indications: psoriasis, psoriatic arthritis, rheumatoid arthritis, juvenile rheumatoid arthritis and ankylosing spondylitis. If a person's health insurance will cover Enbrel, the exact amount will vary. Some patients will be fully covered for Enbrel; others may be partially covered or, in some cases, may have to pay a percentage of the total cost out of pocket.
Amgen has a patient assistance program to help provide discounted medications to people who
qualify, based on income levels and other factors. This program can be reached by calling 888.4ENBREL (888.436.2735).
Updated February 2008
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