A novel preclinical study by Keck Medicine of USC researchers, published in Arthritis & Rheumatology, reveals that a new opioid medication may have the ability to slow the progression of osteoarthritis while being less addictive than commonly prescribed opioid drugs.

The results confirm that the medication activates the kappa opioid receptor, which binds to opioid-like compounds in the central and peripheral nervous systems to alleviate pain, while avoiding penetration of the blood-brain barrier. This results in targeted pain relief with a reduced risk of addiction.

The findings also suggest that the drug prevents the loss of cartilage, which slows the progression of osteoarthritis.

The study’s lead author Alexander Weber, MD, sports medicine physician and orthopaedic surgeon with Keck Medicine, and co-author Denis Evseenko, MD, PhD, vice chair for research and associate professor of orthopaedic surgery at the Keck School of Medicine of USC, tested the drug  by injecting it into arthritic mice knees.

“Arthritis affects nearly a quarter of adults in the United States, many of whom take addictive opioids to manage their pain,” Weber said. “The implications of this study may someday alter how we provide orthopaedic care to significantly reduce the number of patients experiencing long-term pain and addiction.”

More research is needed to advance toward human clinical trials, which are urgent as treatment and pain management options for osteoarthritis are currently limited.

“We hope that the findings of our study will lay the foundations for clinical research to further current understandings of the relationship between kappa opioids and osteoarthritis in humans to improve clinical care and quality of life,” Evseenko said.

 — Gabriella Robison

This study was supported by the National Institutes of Health under award numbers RO1-AR-071724 and RO1-AG-058624, and by the Department of Defense under award number W81XWH-13-1-0465.