Adalimumab (Humira) is a human immunoglobulin G1 (IgG1) monoclonal antibody manufactured by AbbVie Inc. It is indicated (approved for use) for reducing signs and symptoms of RA, inducing major clinical response, inhibiting the progression of structural damage, and improving physical function in adult patients with moderately to severely active RA. It is also indicated for other autoimmune diseases, including juvenile idiopathic arthritis, psoriatic arthritis, ankylosing spondylitis, Crohn’s disease, ulcerative colitis, and plaque psoriasis.1
How does Humira work?
Humira is one of several monoclonal antibodies used to treat RA. Remember that our bodies naturally produce antibodies against bacteria, viruses, and other foreign organisms that invade and pose a threat to our health. Following the example of our bodies, drug makers have engineered different antibodies designed to target the mechanisms that cause a variety of diseases, including RA. Humira binds to human tumor necrosis factor alpha (TNF-α) receptors and, as a consequence, it inhibits TNF-α from carrying out its function in the immune process. It also causes cells that express TNF-α on their surface to rupture and die.1
How is Humira taken?
Humira is usually administered by subcutaneous (under the skin) injection once every 2 weeks. The recommended dose of Humira is 40 mg. In patients who are not taking methotrexate at the same time as Humira, there may be some benefit to increasing the frequency of Humira dosing to once every week. Your doctor will decide how often you should take Humira.1
Make sure you have been instructed about how to give an injection of Humira before you do it yourself. If you have any questions about how to prepare and administer Humira, call your doctor or the Humira patient support number 1-800-448-6472.1
If you forget to take a dose of Humira, inject the next dose as soon as you remember. Then administer your next dose of Humira at the regularly scheduled time. This will get you back on schedule. If you ever have questions about when you should take Humira, call your doctor or pharmacist. If you take Humira more often than you were told, call your doctor.
Are there people who should not take Humira?
There is an increased risk for serious infections and malignancy with Humira. This is because Humira can decrease the ability of the immune system to fight infections. If you are taking Humira and develop any symptoms of an infection contact your doctor immediately. Types of serious infections seen with Humira include tuberculosis, invasive fungal infections (fungal infections that occur inside the body), and bacterial, viral, and other opportunistic infections.1
Humira can cause a worsening of congestive heart failure, demyelinating disease (such as MS), a Lupus-like autoimmune disorder, or cytopenia (a deficiency of cells that make up blood, with symptoms including bruising, bleeding, or persistent fever). If you experience any of these, contact your doctor immediately.1
Humira is a pregnancy category B drug. Results from animal studies indicated no harm to the fetus when Humira was taken during pregnancy. However, because there have been no well-controlled studies in pregnant women, Humira should be used during pregnancy only if it is clearly needed.1
It is not known whether Humira is excreted into human milk. Because of the risk of adverse effects, women who are taking Humira should either not breastfeed or discontinue the drug while breastfeeding.1
What is the evidence that Humira works in RA?
The effectiveness of Humira in RA has been evaluated in five randomized, controlled studies in patients with RA, three of which evaluated Humira in combination with methotrexate, two of which evaluated Humira alone, and one of which evaluated Humira with disease-modifying anti-rheumatic drugs (DMARDs) other than methotrexate.
Disease control and clinical response. Humira alone and in combination with methotrexate resulted in significantly greater percentages of patients achieving disease control (ACR20, 50, and 70) compared with placebo and placebo combined with methotrexate. In one study conducted in 544 patients who had failed previous DMARDs, rates of ACR20 response for Humira 40 mg every other week and weekly at 6 months were 46% and 53%, respectively, compared with 19% for placebo. In another study conducted in 619 patients who had had an inadequate response to methotrexate, the combination of Humira (40 mg every other week) and methotrexate resulted in a rate of ACR20 response at 6 months of 63% compared with 30% for placebo combined with methotrexate. ACR responses with Humira were maintained long-term, with improvements in all components of the ACR score (components include several individual measures, such as number of tender joints, patients global assessment, and disability assessment) maintained over the two years of the study. Furthermore, 20% of patients who received Humira 40 mg every other week experienced a major clinical response (ACR70 over 6 month period).1
Disease control (ACR responses) in two Humira clinical trials1
Study of Humira as monotherapy
Study of Humira plus methotrexate (MTX)
|Response||Humira 40 mg every other week (N=133)||Humira 40 mg weekly (N=103) )||Placebo (N=110)||Humira 40 mg every other week + MTX (N=207) )||Placebo + MTX (N=200)|
|*Statistical significant difference: P<0.01 versus placebo.|
Radiographic response. Patients who received the combination of Humira and methotrexate in the study discussed above also had significantly less radiographic progression, as defined as the change in Total Sharp Score (TSS) at 12 months from baseline (the start of the study), compared with those who received placebo + methotrexate. In fact, there was little change from baseline in the Humira + methotrexate group in TSS and its component scores for joint erosion and joint narrowing.1
Radiographic changes over 1 year: Humira + methotexate (MTX) versus placebo + MTX
|Humira 40 mg every other week + MTX||Placebo + MTX||P-value (significant Humira + MTX vs placebo + MTX)|
|Total Sharp Score||0.1||2.7||<0.001|
|Joint space narrowing score||0.1||1.0||0.002|
Is there a generic form of Humira?
There is no generic equivalent to Humira.