Reports From National Arthritis Meeting 2004
Perspectives of Interest On Arthritis Drugs & New Medications From
Scientists throughout the world are studying many promising areas of new treatment approaches for arthritis and rheumatic diseases. These areas include monoclonal antibody therapy that is directed against a special inflammation factor called the tumor necrosis factor (TNFalpha) (as described below regarding Remicade and Enbrel), and new TNF human antibodies (see Humira below). Also, new non-steroidal antiinflammatory drugs (NSAIDs), with mechanisms of action that are different from current drugs, are on the horizon. There was interesting discussion about the arthritis drug Vioxx that was removed from the market on September 30, 2004 because of risks of heart attack and stroke (see below).Genetic research and engineering are also likely to bring forth many new avenues of earlier diagnosis and treatment in the near future.
Below are perspectives on key research reports presented at the recent national meeting of the American College of Rheumatology:
Vioxx, a drug that has been used to quiet inflammation of arthritis and relieve pain, was withdrawn from the market by its maker, Merck, on September 30, 2004. The reason for the withdrawal was the occurrence of side effects noted in a study that Merck was conducting to see if Vioxx could prevent polyps of the colon and rectum. During this trial, it was noted that there was an increased risk for heart attack and stroke in patients continuing to take Vioxx longer than 18 months.
Dr. Shiel's Perspective: Vioxx is no longer available for use and those taking it should contact their physicians to consider alternative treatment. The risk of heart attack or stroke was small, but real. It is of note that there was no increased risk of stroke in patients taking Vioxx less than 18 months in the study. There has been no indication that any long term damage occurs once the drug is discontinued. The question of interest is a natural concern for inflammation medications of the same class as Vioxx. This class is referred to as Cox-2 inhibitors and includes Celebrex and Bextra NOTE: April 7, 2005, Pfizer agreed to suspend sales and marketing of Bextra in the U.S., pending further discussions with the with the FDA. For more information, please read the FDA press release. . At the national meeting, an FDA spokesperson commented that there is currently an ongoing trial of Celebrex in the prevention of colon polyps. The FDA asked that the 5 year study (now at 2 years) be opened to see if there were signs that Celebrex was increasing the risk of heart attacks or stroke in the study patients. The FDA has allowed the study to continue after reviewing the preliminary data. It therefore seems that not all Cox-2 antiinflammatory drugs are the same. The FDA spokesperson stated that there is no definitive evidence that Celebrex carries an increased risk for heart disease or stroke. It may be, in fact, that different Cox-2 drugs, having different powers of selective action on the Cox-2 enzyme, may have different potential for these blood vessel risks. More data will be forthcoming that will help to clarify risks of drugs used to treat inflammation. Interestingly, Merck has a drug now on the market outside of the U.S. that is used for pain and inflammation relief. The drug, etoricoxib (Arcoxia) was presented in 4 studies at the national meeting and shown to be safe and effective in treating gout, osteoarthritis, and ankylosing spondylitis. Etoricoxib (Arcoxia) is awaiting approval for use in the U.S. and while its maker notes that it has been shown to be safe, I believe it will undergo serious scrutiny of longer term studies prior to approval for the U.S. market.
Remicade (infliximab) is an antibody that blocks the effects of tumor necrosis factor alpha (TNF-alpha). TNF-alpha is a substance made by cells of the body that has an important role in promoting inflammation. TNF promotes the inflammation and its associated fever and signs (pain, tenderness, and swelling) in several inflammatory conditions, including rheumatoid arthritis. By blocking the action of TNF-alpha, infliximab reduces the signs and symptoms of inflammation and stops the progression of joint damage. Remicade is used to treat rheumatoid arthritis, Crohn's disease, and other serious forms of inflammation such as uveitis, psoriatic arthritis, and ankylosing spondylitis. Remicade is given by intravenous infusion over approximately 2 hours, usually every 4-8 weeks.