Research Gets Closer to Development of a Drug to Treat Osteoarthritis

Dr. Loeser

CHICAGO—Many therapies are being investigated to find new interventions for osteoarthritis (OA) that would curb disease progression and joint replacements in an aging population, said Richard F. Loeser Jr., MD, MACR, Joseph P. Archie Jr. Eminent Professor in the Division of Rheumatology, Allergy and Immunology and director of the Thurston Arthritis Research Center at the University of North Carolina at Chapel Hill. Dr. Loeser presented the Oscar Gluck Memorial Lecture at ACR Convergence 2025.

Aging and obesity are two major risk factors of OA, a common form of arthritis that affects more than 500 million people worldwide, noted Dr. Loeser. The number of people living with OA is growing, driven by the aging of baby boomers and increased rates of obesity among adults. In addition, knee and hip replacement surgeries are on the rise because of a lack of disease-modifying drugs to treat pain from an injury, he noted.

“Our goal is to be able to find some new interventions that would slow or stop the progression of OA, so we can reduce the number of joint replacement surgeries,” Dr. Loeser said.

Current Treatment Approaches

Dr. Loeser discussed current approaches to treating patients with OA that include nonpharmacological recommendations, such as exercise, weight loss and self-management programs. Non-steroidal anti-inflammatory drugs (NSAIDs) continue to be the main drugs used to treat joint pain, he said. “When we turn to pharmacological measures, NSAIDs, of course, are still commonly used because we don’t have other great ways of controlling pain pharmacologically.”

Such supplements as glucosamine and chondroitin sulfate lack proven efficacy, Dr. Loeser noted. In addition, the ACR recommends against use of growth factors, cell-based injections and platelet-rich plasma as part of standard care for OA, although they have been studied in clinical trials.

A U.S. Food & Drug Administration decision to name OA as a serious disease should be helpful in future drug discovery efforts, noted Dr. Loeser. The designation provides a regulatory mechanism for approval of a disease-modifying drug faster than what was available in the past. “This is of a lot of benefit to companies that want to get into disease modification,” he said.

Dr. Loeser’s lecture included a discussion of a clinical trial that studied the use of anabolic growth factor called human fibroblast growth factor 18 (FGF18) for cartilage and other joint tissues. The primary outcome measure in a two-year trial was articular cartilage thickness.¹ “There was a significant improvement compared with placebo in the cartilage thickness, but unfortunately, there was no improvement in pain,” he said, “and for disease modification, we really want drugs that improve pain, as well as structure.”