WALTHAM — Repligen Corp. said yesterday that a midstage clinical trial showed one of its drug candidates was no more effective than a placebo in treating bipolar depression.
The results sent Repligen shares tumbling.
The company said the drug, RG2417, was not significantly better than a placebo. The study involved 175 patients who took the drug or the placebo for eight weeks, measuring their symptoms on a 10-item clinical diagnostic survey. Repligen said it will review data from the study and decide if it will continue developing the drug, which is also called uridine.
The company said patients who were enrolled in the study through academic medical centers did significantly better, but in patients who were enrolled through commercial clinical trial sites, there was no difference between RG2417 and placebo. There were 50 patients enrolled through academic sites and 125 through commercial sites. Repligen said it planned to look into those differences.
Repligen is also testing a pancreatic imaging agent and a treatment for Friedreich’s ataxia, a genetic disorder that leads to degeneration of the nerves controlling muscle movements in the arms and legs and the nerve tissue in the spinal cord.
Repligen shares fell $1.37 to $3.54 in Nasdaq trading.