Stopping osteoarthritis: Could recent heart research provide a clue? – Harvard Health Blog
Here is a recent title that I found confusing: Could the first drug that slows arthritis be here?
It’s confusing because it depends on which of the over 100 types of arthritis we’re talking about. We have had drugs that have been slowing rheumatoid arthritis for decades. In fact, more than a dozen drugs approved by the FDA can reduce or even stop joint damage in people with rheumatoid arthritis. We also have drugs that are effective in slowing or stopping gout, another common type of arthritis.
But the title refers to osteoarthritis, the most common type of arthritis. And currently, there is no drug that can safely and reliably slow the rate of this worsening joint disease. This is one of the reasons why many knee and hip replacements are performed: over 1.2 million each year in the United States alone.
A drug that can slow joint degeneration in osteoarthritis has long been the holy grail of arthritis treatments because it could
- relieve pain and reduce suffering for millions of people
- help prevent the loss of function that accompanies osteoarthritis
- reduce the need for surgery, as well as the risk, expense and time required for recovery.
And, it goes without saying that such a drug would generate huge profits for the drug company that first invented it.
Heart disease study could have identified a new treatment for osteoarthritis
According to a new study published in Annals of Internal Medicine, it is possible that such treatment exists and is already being used to treat other conditions. Researchers reanalyzed data on more than 10,000 people who were originally looking to determine whether the drug canakinumab was beneficial for people who had already had a heart attack – yes, heart attack, not arthritis.
Canakinumab inhibits interleukin-1, a substance closely involved in inflammation. And a growing body of evidence suggests that inflammation increases the risk of cardiovascular disease and may predict future cardiovascular problems. All of the study participants had previously had a heart attack. In addition, they had high levels of C reactive protein (CRP) in the blood, an indicator of inflammation in the body.
Every three months, each person was injected with one or more doses of canakinumab or a placebo. Canakinumab appears to work for heart disease: People receiving the 150 mg dose of canakinumab had significantly fewer cardiovascular complications (repeated heart attack, stroke, or cardiovascular death) over about four years. Unfortunately, the rate of fatal infections was also higher in subjects treated with canakinumab.
Another look at this canakinumab study
The reanalysis compares the rates of hip or knee replacements due to osteoarthritis in people receiving canakinumab with the rates in those who received placebo. The study authors believed that since canakinumab reduced inflammation, it might help inflammation in the joints of people with osteoarthritis while providing cardiovascular benefits.
Osteoarthritis has long been considered wear and tear, age-related and non-inflammatory form of joint disease. But over the past decade, research has shown that some degree of inflammation occurs in osteoarthritis. It is therefore no exaggeration to think that a drug like canakinumab could be effective against osteoarthritis. This drug is already approved for a number of inflammatory conditions, including some forms of pediatric arthritis.
The results of this new study surprised me: over about four years, people given canakinumab were at least 40% less likely to have hip or knee replacements than those given placebo.
Please note: these results are preliminary
Before declaring victory over osteoarthritis with canakinumab treatment, it is important to recognize that this trial does not prove that it actually works. It is because the trial
- was not a treatment trial for people with osteoarthritis. Over 80% of the participants had no history of osteoarthritis.
- did not compare x-rays or other imaging tests before and after treatment to confirm the diagnosis of osteoarthritis, or to show that treatment was slowing its progression
- did not assess whether joint pain was present before treatment or improved after treatment. It is possible that the reason there were fewer joint replacements in people taking canakinumab is that the medicine reduced the pain rather than slowing the joint damage. Maybe the medicine can delay the need for joint replacement by reducing symptoms without slowing the progression of joint damage.
- lasted about four years. The results might have been different if it had lasted longer.
- included only people with a history of heart attack and elevated CRP. The results may not apply to people who have no history of cardiovascular problems or normal CRP.
To find out if canakinumab can actually slow osteoarthritis, we need a suitable trial that recruits people with osteoarthritis and compares symptoms and x-rays after treatment with canakinumab or placebo.
Canakinumab is expensive, nearly $ 70,000 / year (although discounts, insurance coverage, and co-payments vary), and is only available by injection. It is not known how many people with osteoarthritis would accept such treatment. While it is found to be very effective in preventing the need for joint replacement surgery, its high cost may be easier to accept.
The bottom line
We need definitive information on the potential of canakinumab or related drugs to treat osteoarthritis and slow its progression. Until then, it is unlikely to become a common option.
If you have osteoarthritis of the knees or hips, talk to your doctor about your options, including maintaining a healthy weight, staying active, and taking pain relievers as needed. Some people get better with walking aids (like a cane) or knee pads (for arthritis of the knee). Joint replacement surgery may be considered as a last resort.
As for new treatments likely to slow the progression of osteoarthritis, we must remain hopeful. But we are not there yet.
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