"Just realize that you're investing without being able to see the full landscape." Those were my parting words when I previewed the FDA decision for Protalix BioTherapeutics (AMEX: PLX) and Pfizer's (NYSE: PFE) Gaucher disease drug, Uplyso.

Looks like that landscape includes some plants that will need a little more water and tender loving care before the FDA approves Uplyso. The companies announced today that the agency wants more information before it'll OK the drug.

As I suggested might be a problem, the FDA is concerned about the manufacturing of Uplyso. The drug is made in plant cells, rather than the traditional mammalian cells with which the FDA has more experience. While in uncharted territory, the agency will be extra cautious to ensure that the manufacturing is up to snuff.

The agency also wants data on the crossover and long-term extension studies that are already ongoing. Assuming the data that has been collected to date is sufficient, it's just a matter of formatting that information and submitting to the agency.

Neither issue sounds like a major delay, but management wasn't willing to give a timeline before speaking with the FDA about exactly what it wants. I'd guess a few months to get the data together plus a six-month review process. Uplyso could be on the market by the end of the year.

The delay isn't the end of the world, but the companies really missed their opportunity to pounce. Genzyme (Nasdaq: GENZ) is getting Cerezyme production back to full capacity after its manufacturing train wreck, and now that the drama with sanofi-aventis (NYSE: SNY) is worked out, there should be fewer distractions. And Shire (Nasdaq: SHPGY) also has a new Gaucher drug, Vpriv, that will continue to establish itself while Protalix and Pfizer wait for an approval.

Better get pruning Protalix and Pfizer.

Interested in keeping track of Protalix as it tries to gain FDA approval? Click here to add it to My Watchlist, which will help you keep track of all our Foolish analysis on Protalix.

Pfizer is a Motley Fool Inside Value selection. 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.

Fool contributor Brian Orelli, Ph.D., doesn't own shares of any company mentioned in this article. The Fool has a disclosure policy.