MRIs revealed the group that received the 100 microgram dose, either once or twice a year, had a slight gain in joint cartilage thickness even after two years. The group given the smaller dosage showed smaller gains. The placebo group lost cartilage during the same period.
None of the study participants experienced any significant improvement in their arthritis symptoms, however.
When the researchers went back and analyzed a small group of the participants — osteoarthritis patients with severe pain and narrow joint space in their knee who were at higher risk of disease progression — that received 100 micrograms of sprifermin every six months showed significant improvement in their symptoms 18 months after their last shot.
"These results support further investigation of sprifermin as a potential osteoarthritis treatment for both structure modification and symptom relief for higher-risk patient populations," said Marc Hochberg, lead investigator and a professor of medicine at UMSOM.
The study was published Tuesday in the Journal of the American Medical Association.