What's the biggest sign that the Food and Drug Administration is all set to approve Regeneron Pharmaceuticals' (Nasdaq: REGN) Eylea? The briefing documents for the advisory committee contained a proposed version of the label.

A drug's label is one of the last things the FDA works on; it would be a waste of time to put one together if the drug wasn't going to be approved. In fact, I've never heard of one being worked on early enough to be included in an advisory panel meeting.

The FDA reviewers' positive opinion of the drug shouldn't come as much of a surprise. After two positive phase 3 trials, Eylea, formerly known as VEGF Trap-Eye, seemed destined for approval as a treatment for macular degeneration. The drug performed as well as Roche's Lucentis, but required fewer applications. Considering the drug is injected directly into the eye, less-frequent dosing is a substantial plus.

Even with positive data, though, there's always a chance the FDA will find a reason to reject the drug. However, the clean bill of health in the briefing documents certainly justifies the 5% jump in Regeneron's stock yesterday.

The panel of outside experts will make its recommendation Friday, but I wouldn't expect a similar jump, even if the vote is unanimous. With a $5.2 billion market cap, a positive recommendation and FDA approval are already baked into the stock; as far as I can see, there's more downside risk than upside potential. Of course, that was true of Vertex Pharmaceuticals (Nasdaq: VRTX) and Human Genome Sciences (Nasdaq: HGSI) recently, and they skated through their FDA approvals without a scratch.

We'll know soon enough whether Regeneron can follow the same path. The PDUFA date for Eylea is Aug. 20, but with the label almost complete, perhaps we'll see an early approval?

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Fool contributor Brian Orelli holds no position in any company mentioned. Click here to see his holdings and a short bio. Motley Fool newsletter services have recommended buying shares of Vertex Pharmaceuticals. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.