Never known for its brevity, the FDA's cardio-renal division released a nearly 300-page briefing document (PDF file) ahead of an advisory panel meeting regarding Cardiome's (NASDAQ:CRME) lead drug. The hearing, scheduled for Tuesday, will weigh the approval of Vernakalant, a treatment for abnormal heart rhythms.

Cardiome and marketing partner Astellas Pharma first filed a New Drug Application for Vernakalant in March 2006, after two successful phase 3 trials, but the application was not accepted because of "deficiencies" in the filing. Cardiome eventually corrected these issues, and it now has a PDUFA action date of Jan. 19, 2008.

Investors wanting only to read the shortcut version of the briefing document and get an overview of the FDA's thoughts (a luxury I didn't have) can skip to page 265, where they'll find the secondary reviewer's opinion of all the other individual opinions in the previous sections.

Numerous FDA reviewers in the briefing document were positive on the drug's efficacy and safety, and raised only minor concerns about Vernakalant. For instance, the pharmacometrics staff found that "the NDA is acceptable," and the statistical reviewers found significant evidence of the drug's efficacy in controlling atrial fibrillation. The secondary reviewer described the Vernakalant data as a "persuasive demonstration of efficacy."

The mere fact that the FDA had to call an advisory committee meeting for opinions on Vernakalant suggests that its NDA is not a shoo-in for approval. (Or rejection, for that matter.) From 2002 to 2004, for example, only 31% of drugs subject to an advisory panel hearing were approved on the first go-round.

Nonetheless, numerous separate FDA reviewers in the briefing document wrote positively on the drug's efficacy and safety, raising only minor concerns about the drug. Unlike Genentech (NYSE:DNA) last week, the odds are extremely high that Vernakalant will get a positive recommendation from the advisory panel.

Thus, the advisory panel will more likely help to delineate Vernakalant's labeling, and determine how broadly the drug will be used in different patient groups. When the drug's PDUFA date rolls around on Jan. 19, investors can thus expect approval, or at worst, a short delay to finalize labeling.

More Foolishness on Cardiome:

Looking for more Foolish drug-stock coverage? Check out the Fool's Rule Breakers newsletter. Discover our full list of market-beating growth-stock recommendations with a 30-day free trial.

Fool contributor Brian Lawler does not own shares of any company mentioned in this article. The Fool has an A+ disclosure policy.