Clinical trial to test FastOA criteria
The Arthritis Foundation, which funded the MOON trial along with the National Institutes of Health and The American Orthopaedic Society for Sports Medicine, launched the FastOA initiative, based on its findings.
FastOA is defined as “the rapid development of OA in those who have sustained a major joint injury.” One criterion for FastOA is older age. Eighteen- to 25-year-olds generally don’t have high risk for injury or OA. “It’s only when you get to your late 20s and 30s where your risk really starts to increase substantially, just like the risk of osteoarthritis does,” Dr. Felson said.
The other major risk factor for FastOA is pain. Pain after ACL reconstruction usually takes a long time to surface. Many people never experience pain. However, for a subgroup of people who get ACL reconstruction, their pain never goes away. “What the MOON data told us was that those are the people who continue to have pain later and who get osteoarthritis quicker,” he added.
The MOON results also informed researchers on the types of patients they should seek out for a future trial. “We wouldn’t just take everybody with ACL reconstructions. We’d take selected people who we knew based on the MOON data were at really high likelihood of developing FastOA,” Dr. Felson said .
Armed with these risk factors, Dr. Felson and colleagues plan to apply FastOA to a new clinical trial, Post-Injury Knee Arthritis Severity Outcomes (PIKASO), that will test the use of metformin, a well-known diabetes drug, in 500 patients at high risk of developing post-traumatic OA in the knee following ACL reconstruction.
Two groups will participate in the PIKASO trial, an initiative of the Arthritis Foundation’s Osteoarthritis Clinical Trials Network (OA-CTN).
“If you have pain at the time of ACL reconstruction, we are interested in you. And if even you don’t have pain, if you’re among older people who need ACL reconstruction, we’re also interested in you,” Dr. Felson said.
People aged 25-40 are eligible for the older category and those 18-40 are eligible for the pain group. It’s important to include younger people in the study, Dr. Felson said. One of his colleagues, a physical therapist, was disabled by a sports injury in her late teens. Now in her 30s, she’s disabled by OA and will have to wait up to 15 years to qualify for a knee replacement.
“It’s a good idea for us to focus in on the younger folks who develop osteoarthritis at a very early age where there’s nothing we can do for them in terms of surgical options for a few years,” he said.
Targeting specific groups means fewer patients will need to be followed over the period of the study, which will lower costs, Dr. Kim said.
Metformin, a popular diabetes drug with a good safety profile, is an ideal treatment for this trial, Dr. Felson said. It’s been tested in multiple animal models and has been shown to protect against OA in all those models.
Researchers will employ imaging and biomechanics measurements to assess changes in joint structure. Eight institutions will participate, including Mass General Brigham, the trial’s clinical coordinating center, and the Cleveland Clinic and University of North Carolina at Chapel Hill, which will coordinate the collection and analysis of MRI data and biomechanical and function assessments, respectively.
“Positive results from this trial would have the potential to enable surgeons to immediately prescribe the drug before a patient undergoes surgery to slow the disease progression, or even fully prevent” post-traumatic OA, according to a statement from the Arthritis Foundation.