New arthritis treatment has no negative side effects
Three million Canadians suffer from osteoarthritis. It’s the common wear-and-tear type of arthritis that presents a challenge for patients day after day. Some people have had to give up a favourite sport, daily walk or gardening. Others find it increasingly difficult to navigate stairs, carry out household chores or keep up with their grandchildren. Now there’s a new drug that can be applied directly to the arthritic joint to help ease the pain. It’s been a long time coming.
Today, with an aging population, there’s a huge need for a safe and effective remedy, and a Canadian company has achieved this historic first. Dimethaid Research has developed Pennsaid, a non-oral NSAID (non-steroidal anti-inflammatory drug) to treat osteoarthritis. And since it’s applied to the skin, it dramatically reduces the risk of stomach complications associated with oral NSAIDs.
Dr. Peter Tugwell, professor of medicine at the University of Ottawa, recently presented his findings on Pennsaid to the European Congress of Rheumatology in Lisbon, Portugal. His study was conducted on 622 Canadian patients suffering from osteoarthritis of the knee. Its purpose was to compare Pennsaid with the maxim daily dose of the oral form of diclofenac, a NSAID. Researchers found Pennsaid was as effective as the oral NSAID in relieving the pain and physical impairment of arthritis.
For years, the standard treatment of arthritis has been the use of oral NSAIDs. They have helped millions of patients in North America. But treating the disease with them has always been a risky affair. Every year, 1,900 Canadians die from the complications of these drugs. That’s a huge price to pay for pain relief.
A study in the United Kingdom used an optical instrument to examine the stomachs of patients using the older NSAIDs. The results were shocking. Doctors reported that after two months of use, one in five patients had a stomach ulcer without symptoms, one in 70 a painful ulcer and one in 150 a bleeding ulcer; one in 1,200 died from a gastric hemorrhage. The situation is worse in the U.S., where 107,000 people are hospitalized every year due to the intestinal side effects of NSAIDs, and 16,500 die.
In a Danish study, researchers tracked 207,000 people for 19 years who had been on NSAIDs to determine the extent of intestinal bleeding. It showed that NSAIDs increased the risk of bleeding five times. For those over 75 years of age, the risk was 27 times greater.
But in addition to life-threatening complications, many patients using oral NSAIDs complain of abdominal pain, indigestion, nausea and diarrhea. And there may be abnormalities in liver function tests. The gastrointestinal problems occurred because the early NSAIDs destroyed an enzyme called COX-1 that normally protects the stomach’s lining from inflammation.
So researchers did the obvious thing. They designed new NSAIDs called COX-2 inhibitors to preserve COX-1 and protect the stomach. Studies show these NSAIDs are an improvement, but they have not eliminated serious complications.
There is another aspect of NSAID medication that is rarely explained to patients suffering from arthritis. Frequently, I see patients who swallow NSAIDs as if they were M&M candies. They have never been informed that NSAIDs are powerful drugs that can have adverse effects on liver, kidneys or heart, especially in older patients. Other doctors I talked to are pleased this isn’t likely to happen with Pennsaid since it’s not taken by mouth but is delivered directly to the pain site with little absorption into the bloodstream.
The availability of a stomach-friendly NSAID fills a big void in therapy. Pennsaid solution is applied to the affected knee four times daily. The most common side effect involves a minor skin reaction, with dryness and irritation at the site of application in a few patients.
Although Pennsaid is only approved for treating arthritis of the knee, good sense indicates it should also help other joints, such as those in the hand.
Pennsaid will undoubtedly save lives and be a godsend for those suffering from painful arthritis. But it will also help to save millions of dollars spent treating the complications of orally administered NSAID medication.