Arthritis drug new rheumatoid
For people with inflammatory conditions who have tried other medications with little success, TNF-alpha inhibitors may provide some relief. Also known as biologic response modifiers, these new prescription drugs block the action of tumor necrosis factor-alpha (TNF-alpha), a protein that's present in larger quantities in the body with certain conditions, such as rheumatoid arthritis. But, like all medications, TNF-alpha inhibitors may cause side effects that a patient should consider when deciding to take these drugs. Balancing the side effects and financial cost with the potential improvements in the quality of life that could come from taking TNF-alpha inhibitors is something a patient needs to discuss with their rheumatologist. How TNF-alpha inhibitors work
TNF-alpha inhibitors block the action of TNF-alpha in the body. By preventing TNF-alpha from acting, these drugs reduce inflammation and other signs and symptoms a patient may have. Three TNF-alpha inhibitors are available by prescription. Adalimumab (Humira) is the newest TNF-alpha inhibitor. The doctor might prescribe it alone or in combination with other medications to treat rheumatoid arthritis. A patient injects adalimumab under the skin of the thighs or stomach every other week, or sometimes weekly. Adalimumab can be used alone, or may also be prescribed with other medications along with it, such as methotrexate. Research conducted since Food and Drug Administration approval of adalimumab (Humira) shows that in rare circumstances the medication has been associated with severe allergic reactions (anaphylaxis) as well as the blood disorder cytopenia. Discontinuation of the medication is suggested if a patient experiences an allergic reaction, such as difficulty breathing, hives and itching, or a weak or rapid pulse, or if they observe signs and symptoms of a blood disorder, such as a persistent fever, bruising, bleeding or paleness. Etanercept (Enbrel) can be used alone or in combination with other medications. Etanercept is injected once or twice a week in the thigh, stomach or upper arm. The doctor might recommend etanercept if the disease hasn't responded to other medications or if a patient has a more advanced stage of the disease. Research conducted since FDA approval of etanercept (Enbrel) shows that in rare circumstances the medication has been associated with severe — even fatal — blood disorders or the worsening of existing blood disorders. Infliximab (Remicade) differs from the other TNF-alpha inhibitors in that it's made from human and mouse proteins rather than human-like proteins. Infliximab is given as an intravenous (IV) infusion over two or three hours rather than a self injection. A patient may receive two or three IV infusions over several weeks or months. For rheumatoid arthritis, the usual dosage schedule is three infusions over the first six weeks, then once every eight weeks after that. The doctor will likely also prescribe methotrexate along with infliximab. Research conducted since FDA approval of infliximab (Remicade) shows an increased risk of lymphoma and abnormal cell growth with this medication. The three TNF-alpha inhibitors have never been tested against each other, so doctors don't know if one works better than the others for rheumatoid arthritis.
Common side effects of TNF-alpha inhibitors
• Redness TNF-alpha inhibitors may cause other side effects: • Runny nose More serious reactions to TNF-alpha inhibitors include: • Infections. TNF-alpha inhibitors decrease the action of the proteins that stimulate the white blood cells, limiting the body's ability to fight infections. A number of infections have been reported in people taking TNF-alpha inhibitors, ranging from upper respiratory infections to serious infections such as tuberculosis. For this reason, a physician will ask about any current or recurring infections a patient may have and might test for various infections. The doctor will also want to test for tuberculosis before prescribing a TNF-alpha inhibitor, as well as fungal infections such as histoplasmosis and coccidiomycosis (valley fever), since these infections may worsen and be more severe if a patient is being treated with a TNF-alpha inhibitor. The risk of serious infection increases if a person takes a TNF-alpha inhibitor along with the interleukin-1 antagonist anakinra. Anakinra should not be taken along with a TNF-alpha inhibitor. If a patient develops an infection while taking these medications, they may have to stop the treatment until the infection has been successfully treated. Antibiotics
Gene therapy
• Tacrolimus (Prograf). Tacrolimus is an immunosuppressant that blocks the action of T cells — certain white blood cells that play a role in activating other cells in the immune system. Tacrolimus is already approved for people who've had liver or kidney transplants to keep their bodies from attacking their new organs. Researchers hope tacrolimus can help people with rheumatoid arthritis by stopping T cells from causing inflammation. Abatacept and other costimulation modulators render T cells inactive by interfering with the process that turns T cells on. If they don't turn on, T cells can't activate the cells that cause the inflammation and joint damage of rheumatoid arthritis. Abatacept is the only costimulation modulator currently available to treat rheumatoid arthritis in the United States. People with moderate to severe rheumatoid arthritis who haven't adequately benefited from methotrexate or tumor necrosis factor-alpha (TNF-alpha) inhibitors, including adalimumab (Humira), etanercept (Enbrel) and infliximab (Remicade), can consider abatacept. Studies have found that abatacept can reduce the signs and symptoms of rheumatoid arthritis. It can also reverse some signs of joint damage. Abatacept is given as intravenous therapy. Each infusion takes about a half-hour. A patient receives abatacept infusions every two weeks for the first month, then every four weeks. Some people may continue to take methotrexate while on abatacept. People with chronic obstructive pulmonary disease (COPD) shouldn't take abatacept because it can worsen the signs and symptoms of COPD. Also people currently taking TNF-alpha inhibitors shouldn't take abatacept.
Serious side effects have occurred in people taking abatacept for rheumatoid arthritis. Carefully weigh the expected benefit from this drug against the possible side effects to decide whether abatacept is a good option. The most common side effects of abatacept include: • Back pain • Infections. Because abatacept interferes with T cells — an important component of the immune system — a patient may be more likely to develop infections while taking this drug. Most infections associated with abatacept are mild, with upper respiratory tract infections being most common. Other types of infections include sinus infections, urinary tract infections, the flu and bronchitis. Severe infections, such as pneumonia, are possible. Despite continued research, doctors still aren't sure exactly what causes rheumatoid arthritis. However, that hasn't stopped researchers from continuing to develop new drugs to treat rheumatoid arthritis. Abatacept has helped to prove that T cells play an important role in the disease. Researchers continue to look for new ways to slow or stop T cells from activating.
Just over half of the RA patients in a new study saw their symptoms improve when treated with Rituxan in combination with the disease-modifying antirheumatic drug (DMARD) methotrexate. Patients taking low doses of Rituxan responded as well as those given higher doses, and the addition of steroids during treatment did not appear to improve outcomes. All of the patients in the study had previously failed treatment with methotrexate or other DMARDs. About a third had been treated with biologic agents that work via a different pathway, such as the drugs Enbrel, Humira, and Remicade. An estimated 3 million adults in the U.S. have rheumatoid arthritis, a progressive autoimmune disease that involves inflammation of the joints and surrounding tissues. Over the years, RA can destroy joints, ligaments, tendons, and even bone. Biologic drugs that suppress inflammation-causing immune system cells, or cytokines, are new to the treatment of rheumatoid arthritis. While very expensive -- costing between $16,000 and $20,000 a year, according to one cost analysis -- they hold the promise of eliciting better outcomes than traditional RA treatments with fewer side effects. The study of Rituxan included 465 patients with moderate to severe RA treated with Rituxan or placebo plus methotrexate -- with and without steroids. The study is published in the May issue of the journal Arthritis and Rheumatism. It was funded by drug makers Genentech, Biogen, and Hoffmann-La Roche, which market the drug jointly. Genentech and Biogen are WebMD sponsors. There were nine different treatment groups, designed to better understand which doses of drugs were most effective and whether adding steroids improved outcomes. A total of 55 percent of the patients treated with the higher-dose Rituxan regimen showed a 20 percent or better improvement after six months, compared with 54 percent of patients on the low-dose regimen and 28 percent of patients taking a placebo. Steroids, whether given in the vein or by mouth, didn’t add any further improvement than Rituxan and methotrexate alone. But intravenous steroids given prior to Rituxan made the drug more tolerable. Another promising new drug is dnaJP1. The new drug, dnaJP1, is a peptide derived from a naturally occurring protein, dnaJ, which generates inflammation in RA patients, whose inflammatory-control mechanisms are impaired. The impairment causes the body's T cells -- which trigger inflammation to kill and clear foreign pathogens in the body -- to attack the body's own tissues. "In essence, we re-educated the immune system T cells to be tolerant of the dnaJP1 amino acid sequence, which would usually contribute to inflammation in rheumatoid arthritis patients," Dr Salvatore Albani of the University of California, San Diego, said.
It takes several years for drugs to move from a new idea, through research and development and, eventually, to approval. Some drugs that seemed promising in small studies won't pan out in larger clinical trials and may never receive approval. Though new developments may provide hope for the future, know that nothing is certain.
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