USC Research Finds Cartilage Growth Regulator

A team led by University of Southern California (USC) scientist Denis Evseenko, M.D., Ph.D., an associate professor of orthopedic surgery at USC, hopes to delay or reduce the need for joint replacement operations with an injection. He and his team have been studying a new small molecule for arthritis called “Regulator A of Cartilage Growth and Differentiation,” or RCGD 423.

The molecule works on the body’s glycoprotein 130 receptor, which receives two types of signals. The signals either promote cartilage development or trigger chronic inflammation. RCGD 423, the researchers say, enhances the reception of the cartilage growth signals while blocking the inflammatory ones that lead to degeneration.

The researchers also found that during in vitro studies, the drug helped joint cartilage cells proliferate. When they injected RCGD 423 into mice, they observed improved healing of cartilage damage.

“The goal is to make an injectable therapy for an early to moderate level of arthritis,” said Evseenko. “It’s not going to cure arthritis, but it will delay the progression of arthritis to the damaging stages when patients need joint replacements, which account for a million surgeries a year in the U.S.”

Evseenko is especially concerned about young victims of osteoarthritis. Joint replacement is their only option and younger patients may end up with limited mobility or a need for further surgeries.

Evseenko is also looking at other alternatives to joint-replacement surgery, including using pluripotent stem cells to regenerate cartilage. As he sees it, the potential of RCGD 423 does not lie only in arthritis. He envisions a whole new class of anti-inflammatory drugs. He believes there may be applications for use of the molecule in rheumatoid arthritis, lupus, neurological and heart diseases.