Repligen imaging agent misses main study goal

Associated Press

WALTHAM -- Repligen Corp. said today that its pancreas imaging agent RG1068 did not meet its main goal in a late-stage clinical study.

Shares plunged 81 cents, or 17.4 percent, to $3.86 in morning trading. The stock has ranged from $3.55 to $5.85 over the past year.

Repligen is testing RG1068 to determine if it can make magnetic resonance imaging scans more effective in helping physicians find structural abnormalities in the pancreas without losing specificity. In the study, RG1068 was given to patients with a history of pancreatitis, or inflammations of the pancreas.

Three radiologists worked on the study and Repligen said it would have been a success if at least two of them reported a significant improvement in sensitivity. The company said one radiologist reported such an improvement, and while another reported improvement, the difference was not statistically significant. It said all three reported a minimal loss in specificity.

In the trial, 258 patients had an MRI with or without RG1068. The results were confirmed with an endoscopy, a more invasive procedure in which a tube containing a very small camera is inserted into the body.

Repligen said the combined data from the study showed a statistically significant improvement in sensitivity. The company said the study met other goals, including improved image quality, ability to see all segments of the patients' pancreatic duct, and greater physician confidence in ability to find abnormalities in duct compared to MRI alone.

The company said it will discuss the study results with the Food and Drug Administration in early 2010.

Repligen said there were no serious side effects from RG1068. The most common side effect of endoscopy was acute pancreatitis requiring hospitalization.