UCSF Research Paved Way for Spine Condition Drug

August 06, 2003
News Office: Wallace Ravven

A UCSF study has led to FDA approval of a drug to treat a painful and disabling spinal condition.

The FDA in July approved the immune-blocking drug etanercept for ankylosing spondylitis (AS), a chronic inflammatory arthritis characterized by joint stiffness, pain and extra bone growth that can result in partial or complete fusion of the spine. The drug is the first approved for this condition, which affects some 300,000 people in the US.

It was in May of 2002 when Dr. John Davis, a rheumatologist at UCSF Medical Center, and his colleagues first reported in the New England Journal of Medicine that 75 percent of patients taking etanercept found relief from their symptoms. The drug, already approved and used for rheumatoid arthritis, was the only drug to relieve intense pain from spinal inflammation in most patients in the UCSF study.

Recently, Davis, a UCSF assistant professor of medicine, led a larger, international study with 277 patients which confirmed the earlier promising findings. The results were reported in June at an international meeting on rheumatism and related conditions. A few weeks later, the FDA approved etanercept specifically for treatment of AS. A full report on the larger study will be published in the journal Arthritis & Rheumatismlater later this summer.

Etanercept is known by the trade-name Enbrel. It is a genetically engineered protein used for treatment of rheumatoid arthritis and other inflammatory ailments. It binds to the naturally occurring tumor necrosis factor (TNF) and inhibits its action in the body. TNF promotes inflammation and is found at elevated levels in patients with AS, Davis said.

The drug may reduce spinal inflammation and actually slow the progress of the disease.

In AS, the bones of the spine may grow together, causing the spine to become rigid and inflexible. Other joints such as the hips, shoulders, knees or ankles also may become involved.

"Until recently, it has really been disheartening to treat people in so much obvious pain, yet have so few therapeutic options to help them," said Davis at the time of the NEJM report. "Highly targeted biological agents such as etanercept offer a way to block the specific immune reaction that has gone awry and dramatically change the course of this disabling disease."

Co-author on the original study with Davis was Dr. Jennifer Gorman, fellow in rheumatology, and Dr. Kenneth E. Sack, a rheumatologist at UCSF Medical Center and a UCSF professor of clinical medicine.