Dov drug misses mark in back pain trial

According to Dov an unusually high placebo response rate was the single major contributory factor to the failure of the trial. The company also said that the severity of the disease in the patients tested may have had an effect on the final result, noting that placebo response decreased as desease severity worsened and relative effect of bicifadine increased

The mean placebo response, the change in pain score from baseline to end of treatment among all patients, was 25mm on the 0-100mm visual analog scale (VAS). This is a substantially higher placebo response than has previously been reported in chronic low back pain (CLBP) trials and thus made it difficult to see a beneficial effect of bicifadine.

Additional analyses identified two major subgroups of patients – in total, approximately 50% of the patients in the study – in which the effectiveness of bicifadine in pain control was substantial. These were patients with chronic low back pain along with pain radiating down the leg (sciatica) and patients with a moderate to severe level of functional disability at baseline.

“While we are surprised and disappointed by the trial failure, we are encouraged by the effect of bicifadine in the two major subgroups of study 020 patients,” said Dr Warren Stern, senior vice president of drug development at Dov, “as a next step, Dov is assessing how it can use this information to positively impact the likelihood of success in our ongoing phase III trial in this indication.”