LIVERPOOL, ENGLAND – There was no significant reduction in pain from knee osteoarthritis (OA) with the use of investigational cannabidiol (CBD) gel ZYN002 in a phase 2a trial presented at the World Congress on Osteoarthritis.
The mean reductions in baseline knee pain scores from study entry to a 12-week assessment were –2.4 for placebo and –2.6 (P = .5) and –2.8 (P = .25), respectively, for a 250-mg and a 500-mg formulation of the gel.
Sara Freeman/MDedge
Dr. David Hunter
While there was a trend for benefit, it was “neither statistically or clinically significant,” reported David Hunter, MBBS, PhD.
However, he observed that a significantly (P = .016) greater number of patients who received the 250-mg dose (52.7%) were “composite responders,” compared with patients who received placebo (34.1%). A composite response was defined as at least a 30% reduction in pain, and a 20% decrease in WOMAC physical function subscale score at the last observation.
Although the percentage of composite responders was also higher than placebo with the 500-mg dose, the difference wasn’t significant (45.1% vs. 34.1%; P = .0169).
Post-hoc analyses also suggested that perhaps some patients may benefit more than others, reported Dr. Hunter, professor of medicine at the University of Sydney and the Royal North Shore Hospital, Sydney.
For example, patients with baseline pain scores or 7 or more had greater mean reduction in pain at 12 weeks with both doses of the gel combined than placebo at week 4 (–2.2 vs. –1.6; P = .029), although the difference was not significant at week 8 (–3.0 vs. –2.2; P = .05) or 12 (–3.3 vs. –2.5; P = .086).