Anti-inflammatory Drug May Help Osteoarthritis Patients Avoid Joint Replacement

Osteoarthritis (OA) is the most common joint disorder in the United States. Although healthcare providers can prescribe drugs to relieve pain, there is currently no definitive treatment for OA. People with osteoarthritis typically need to undergo hip or knee replacement surgery—which can be both costly and painful.

However, a new study conducted by the CANTOS (Canakinumab Anti-inflammatory Thrombosis Outcomes Study) trial group suggests de facto OA joint replacements could soon become a thing of the past thanks to a drug called canakinumab. The drug is typically used to treat certain rare rheumatic conditions marked by widespread inflammation. But researchers found that the use of the canakinumab reduced the need for hip and knee replacements by over 40% in study participants, irrespective of dose.

In their paper, which was published in Annals of Internal Medicine on August 4, the researchers examined the impact of canakinumab on OA over a span of five years. But the study participants—all men—weren't recruited for an osteoarthritis study.

This research began with a 2017 study focused on the role of canakinumab in heart disease. Researchers noticed the drug reduced the risk of heart attack and stroke by lowering C-reactive protein levels. High levels of C-reactive protein are linked to osteoarthritis. And so, a second study began.

While the preliminary results are encouraging, more research is needed before the drug can be developed into an osteoarthritis treatment.

Potential Uses for Canakinumab

The preliminary CANTOS trial, published in 2017 in The New England Journal of Medicine, included 10,061 men who were given a 50 milligram (mg), 150 mg, or 300 mg injection of either canakinumab or a placebo control every three months for five years. The followup study tracked hospital trips for surgery among participants, including joint surgery. That's when the potential link to osteoarthritis became clear: the incidence rate for hip and knee replacements decreased by 40% and 47%, respectively, in patients who received canakinumab.

Despite these encouraging results, researchers say the study has its drawbacks. The CANTOS trial was conducted on an exclusively male and a predominantly diabetic group. Therefore, anti-arthritic benefits cannot automatically be extrapolated to women.

“Previous smaller trials have not shown benefits from anti-interleukin-1 therapy,” Philip Conaghan, MD, one of the lead researchers in the CANTOS trial, tells Verywell. Additional research is needed to find out why the CANTOS trial was different.

Conaghan says scientists have found new applications for canakinumab in other diseases as well.

“It’s also used to treat uncommon autoimmune diseases, such as Stills disease, and highly-resistant gout,” he says.

Can Doctors Start Prescribing Canakinumab For OA?

Conaghan says it’s still too early to recommend canakinumab as a treatment for osteoarthritis.

Canakinumab may lower the immune system's ability to fight off infection, something that's an especially big risk during a global pandemic.

“Even though canakinumab could prove to be beneficial, the risks are too high right now,” Giuseppe Aragona, MD, medical advisor at Prescription Doctor, tells Verywell. Aragona was not involved in the CANTOS study.