DOV Pharmaceutical has announced the results of its Phase III trial of bicifadine in patients with chronic low back pain (CLBP).
In the trial, bicifadine did not achieve a statistically significant effect relative to placebo on the primary endpoint of the study (reduction in pain at the end of treatment) at any of the doses tested. DOV now has determined that an unusually high placebo response rate was the single major contributory factor to the failure of the trial.
In the trial, the mean placebo response -- the change in pain score from baseline to end of treatment among all patients -- was 25 mm on the 0-100 mm Visual Analog Scale (VAS). This is a substantially higher placebo response than has previously been reported in CLBP trials and thus made it difficult to see a beneficial effect of bicifadine.