TNF Inhibitors Effective for Treatment of Rheumatoid Arthritis
Two members of a new class of drugs have been found to reduce the joint damage associated with rheumatoid arthritis. Rheumatoid arthritis (RA) is an inflammatory disease that causes pain, swelling, stiffness, and progressive loss of function in the joints.
Two studies published in the New England Journal of Medicine evaluated the effectiveness of TNF inhibitors, drugs that neutralize the inflammatory protein known as tumor necrosis factor (TNF). TNF is overproduced in the joints of patients with rheumatoid arthritis and is believed to be responsible for much of the joint damage in RA.
In one study, conducted at the Johns Hopkins University, in Baltimore, etanercept (Enbrel) was compared to methotrexate in 632 patients with early stage rheumatoid arthritis. Etanercept acted more rapidly to decrease symptoms than methotrexate. In addition, etanercept was more effective at slowing the progress of joint erosion; the rate of joint damage, as measured by x-rays, was significantly reduced in the etanercept group compared to the methotrexate group. After one year of treatment, 72 percent of the etanercept patients had no progression in joint erosion compared to 60 percent of the methotrexate-treated patients.
The second study, conducted at the University of Texas Southwestern Medical Center in Dallas, followed 428 patients with chronic, active rheumatoid arthritis for 12 months. The researchers found that a combination of the TNF inhibitor infliximab (Remicade) and methotrexate significantly reduced the symptoms of RA and halted progression of joint damage compared to treatment with methotrexate alone. Nearly 52 percent of the patients taking the infliximab and methotrexate combination showed symptom reductions, compared with 17 percent of methotrexate-only patients. x-ray examination showed that joint damage came to a halt in patients given the drug combination. In addition, joint damage decreased in 40-55 percent of patients on the combination therapy, implying that some damage had been repaired. Meanwhile, joint damage progressed in the group given only methotrexate. The combination therapy, which was well tolerated, also significantly improved quality of life.
Methotrexate, the standard rheumatoid arthritis medication, was approved more than a decade ago for treating certain types of arthritis and skin conditions. However, it can cause serious side effects including liver damage. In contrast, both TNF inhibitors were well tolerated.
An estimated one percent of the adult U.S. population has rheumatoid arthritis, and it is about two to three times more common in women than men.
May 2001 Update
New Medication Approved to Treat Eczema
Atopic dermatitis is a chronic, hereditary skin condition that causes redness, itching, and oozing lesions. It mainly affects children but can persist into adulthood. Doctors often prescribe oral or topical corticosteroids for serious cases. But while steroids are very effective at quieting inflammation, they can have adverse side effects. Steroid creams may cause thinning of the skin and decreased collagen production, while oral corticosteroids can have more serious adverse effects.
Now, dermatologists have high hopes for a new ointment, tacrolimus (Protopic), which was recently approved by the FDA to treat moderate to severe eczema in patients who cannot tolerate or are not adequately helped by standard therapies. The FDA approved tacrolimus on the basis of three 12-week studies that found 90% improvement in about one-third of the patients who used the medication. Two additional one-year studies, also considered by the FDA, found that adults who used the drug intermittently over the course of the year had no adverse effects except temporary burning and stinging. Because tacrolimus can increase sensitivity to ultraviolet (UV) light, users should avoid sunlight, tanning beds, and treatment with UVA or UVB light.
March 2001 Update
Preventing Bone Loss from Steroid Therapy
Corticosteroids are very effective in reducing inflammation. These drugs may be taken in many forms: injected directly into a shoulder to treat tendonitis, inhaled into the lungs to calm the inflammation characteristic of asthma, or as creams to treat skin rashes. The pill form (typically prednisone and Prednisolone) may be used to treat conditions such as arthritis or lupus. One of the serious side effects of these drugs when taken for long periods is loss of bone mass essentially, osteoporosis.
Bisphosphonate drugs (used to treat osteoporosis) have been shown to prevent bone loss associated with corticosteroid therapy. A recent study confirmed that a newly developed bisphosphonate, risedronate, helped prevent bone loss associated with steroid use. While treatment with risedronate improved bone mineral density, it is too early to tell for certain if it can reduce the fracture rate for patients on steroids.