The FDA has placed a rare clinical hold on a trial sponsored by Corautus Genetics after the company reported three severe adverse events in a 10-day period.

Corautus Genetics announced March 14 that it was voluntarily suspending its GENASIS trial of the VEGF-2 therapy, designed to treat cardiovascular (severe angina) and peripheral vascular disease. This action came a few weeks after encountering three cases in which enough fluid built up in the patients' pericardial sacs to put pressure on their hearts, a life-threatening event that required immediate intervention to drain away the excess fluid. An additional case had occurred in the summer of 2005, making a total of four cases out of the 295 enrolled subjects -- a 1.36 percent occurrence rate.

"We did not, and still do not, believe the events were related to the therapeutic; however, patient safety is a prime concern, so we immediately took action," President and CEO Richard Otto said in a press release.

Corautus reported the problem to the FDA, which imposed the clinical hold, while the company sent a group of its own employees and representatives of Boston Scientific, which developed the Stiletto brand catheters used to deliver the gene therapy, to investigate the problem. The company has now filed its official response to the clinical hold and developed a plan to handle such problems should they happen again. Otto said the company hopes to start a Phase III trial soon.