What are the long-term risks of taking the biologic treatment Humira?

Q. Are there any concerns with taking Humira long-term? I know it can be linked to TB. I have been on it for two years for psoriatic arthritis.

A. As with any medication, there is some risk with long-term use of adalimumab (Humira). However, its safety profile is quite good.

Adalimumab is an injectable "biologic" treatment approved for a number of conditions, including moderate to severe rheumatoid arthritis, psoriatic arthritis, Crohn's disease, ulcerative colitis, and plaque psoriasis. It's called a biologic because it is produced by a living system such as a microorganism or animal cell. Other biologic agents that act in a similar way include certolizumab (Cimzia), etanercept (Enbrel), golimumab (Simponi), and infliximab (Remicade). These biologics are called anti-TNF drugs. (The TNF stands for "tumor necrosis factor.")

You are quite right about the link to tuberculosis (TB). However, that's a problem primarily in people who have been exposed to TB in the past. That's why doctors check for TB before starting a patient on these drugs. If a blood or skin test is positive for prior TB exposure, a chest x-ray and full examination are performed to look for active infection. No one with active TB should receive an anti-TNF drug. For those with a positive TB test but no active infection, antibiotic treatment is available to reduce the risk of TB while taking adalimumab.

Other possible side effects of adalimumab use include:

• allergic and immune reactions
• upper respiratory infections
• reactivation of hepatitis B among people who carry this virus
• nerve injury that may mimic multiple sclerosis
• low blood counts
• increased risk of certain cancers (primarily skin cancers and lymphoma, a cancer of the lymph nodes; the magnitude of this increased risk is under considerable debate)
• worsening of heart failure
• infections other than TB, including bacterial and fungal infections
• lupus-like disease, including joint pain, rash, and chest pain.

Despite the number of potentially serious side effects, their rate is quite low. And for many of them, there's no clear link with long-term use. For example, when TB complicates anti-TNF treatment, the infection usually occurs soon after starting the drug.

If you have concerns about any of the medications you take, talk to your doctor. Your risks may be higher or lower than average based on your overall health, the other medicines you take, and where you live.

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