Abbott Laboratories announced that the U.S. Food and Drug Administration (FDA) approved the biologic drug Humira (generic name adalimumab) for reducing signs and symptoms of active arthritis in patients with psoriatic arthritis. Humira is also approved to treat rheumatoid arthritis. The National Psoriasis Foundation welcomes the news as another treatment option for psoriasis and psoriatic arthritis patients.
How will people use it?Patients take Humira at home by giving themselves an injection of 40 milligrams (mg) every other week, similar to diabetes patients who give themselves insulin injections. Humira is designed to be taken continuously to maintain improvement. The medication can be used alone or in combination with methotrexate or other DMARDs (disease-modifying antirheumatic drugs) under a doctor's supervision.
How effective is it?In a double-blind, placebo-controlled study of 313 patients with active psoriatic arthritis, researchers monitored joint symptoms and the skin.
Improvements in both skin and joint symptoms were seen as early as two weeks and continued to improve over time.
Determining arthritis measurement scores in those using 40 mg of Humira every other week:
At week 12, nearly 60 percent achieved 20 percent improvement
At week 24, nearly one quarter achieved 70 percent improvement
Nearly 70 patients in the trial had skin lesions involving greater than 3 percent body surface area and were treated with Humira. In measurements of psoriasis severity by week 24:
75 percent achieved 50 percent improvement
Nearly 60 percent achieved 75 percent improvement
More than 40 percent achieved 90 percent improvement Humira is not approved by the FDA for the treatment of psoriasis, but studies of its effectiveness in treating this disease are being conducted.
How does it work?Humira 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.
Humira 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.
What are the side effects?Common side effects in psoriatic arthritis patients included upper respiratory tract infections, injection site reactions and high blood pressure.
According to the product label information, in studies of rheumatoid arthritis patients, the most common side effects included:
upper respiratory infections
abdominal pain
headache
rash
injection site reactions
urinary tract infection
These side effects were generally mild and did not cause most patients to stop taking Humira. These events happened most often after the first dose of Humira and may decrease after additional doses.
Humira treatment should not be started in someone with an active infection, and it may not be recommended for someone with a history of recurring infections. People taking Humira should be monitored for signs of infection, and if a serious infection develops, the medication should be stopped.
Tuberculosis, invasive fungal infections and other serious infections have been reported in Humira patients; some of the infections have been fatal. The infections often occurred in patients who were also using other medications that affect the immune system, such as methotrexate.
People should be evaluated for latent TB infections by getting a TB skin test prior to treatment with Humira. Patients with evidence of TB exposure might require additional testing and treatment before starting Humira.
There have been rare reports of central nervous system disorders in association with the use of Humira. Doctors are advised to use caution in considering the use of Humira in patients with pre-existing or the recent onset of central nervous system disorders, including multiple sclerosis. About 12 percent of patients develop antibodies to the medication, and these people are more likely to have an allergic-type reaction to the treatment.
The FDA has reviewed the association between TNF-alpha medications such as Humira 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. Humira's safety and side effects continue to be monitored by Abbott Laboratories and the FDA.
