71 percent of the subjects completed the treatment protocol. Radiographs were obtained from 85 percent of all subjects at 30 months. After 16 months of treatment, the mean loss of joint space width in the diseased knee in the doxycycline group was 40 percent less than in the placebo group. After 30 months, it was 33 percent less. Yet, despite significantly slowing disease progression, doxycycline did not reduce the severity of joint pain. However, mean pain scores at baseline were low in both treatment groups, leaving only limited opportunity to demonstrate improvement in joint pain. On the other hand, the drug significantly reduced the frequency with which subjects reported increases in knee pain 20 percent or greater than the level of pain they had at their previous semi-annual visit.
Notably, doxycycline seemed to have no effect on joint space narrowing or pain in the relatively disease-free knee. In both knees in both treatment groups, the rate of joint space narrowing was more than twice as rapid in subjects who reported frequent increases in pain than in those with a stable pain score. "Joint pain may serve as an indicator of synovitis that leads to cartilage destruction," observes the study's leading author, Kenneth D. Brandt, M.D.
Throughout the trial, fewer than 5 percent of all subjects reported side effects. In general, doxycycline seemed to be well tolerated. Subjects in the active treatment group experienced the unexpected side benefits of fewer urinary tract and upper respiratory tract infections than their placebo counterparts.
In conclusion, in this study, doxcycyline showed benefits in slowing the rate of joint space narrowing in knees with established OA. Whether this drug has any value in the early treatment and sympto
'"/>
Contact: Amy Molnar
amolnar@wiley.com
John Wiley & Sons, Inc.
28-Jun-2005