Savient shares skyrocket on FDA's Krystexxa remarks

Shares of Savient Pharmaceuticals barreled ahead more than 50 percent this morning after analysts had a chance to digest FDA staff remarks on the gout drug Krystexxa, which is up for a panel review next Tuesday.

The agency staffers said they weren't disputing data on the efficacy of the drug, but did want to focus on cardiovascular safety after seven people died in the study. In many cases, a remark like that on safety would be the kiss of death for investors. But there was a caveat. Many of the patients in the pivotal study had underlying health risks, the FDA staff noted.

"There was uncertainty concerning whether the cardiovascular adverse events represent a genuine safety signal or whether they represent expected adverse events related to underlying risk factors," the FDA stated.

And analysts quickly championed the remarks, saying that the agency's efficacy and safety review is largely positive and bodes well for an approval."The tone was very positive in the documents," Collins Stewart analyst Salveen Kochnover told Dow Jones. "There is really nothing unexpected in the documents."

- read the report from Dow Jones