Shares of Dynavax (NASDAQ:DVAX) fell 33% in November, after a Food and Drug Administration advisory committee voted 8-5 against its hepatitis-B vaccine Heplisav. Despite voting 13-1 in favor of the drug's efficacy -- because it outperformed the current standard drug in this space in terms of percentage of adults protected after a period of seven months -- committee members expressed concerns over insufficient safety data. Dynavax has its PDUFA date in late February, and shares would soar upon approval, but investors may be asking too much to think that the FDA will forgo its panel's recommendation regarding safety.

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