It's the binary news events -- clinical trial results and Food and Drug Administration approvals -- that make drug developers so fun to invest in, and so hard to stomach ... sometimes all at the same time. Let's take a look at a few companies expecting FDA decisions this month.

Pain-free decision
Johnson & Johnson (NYSE:JNJ) is waiting on a Nov. 23 decision on its pain reliever tapentadol. The drug provides relief from pain without the prevalence of strong side effects -- such as nausea, vomiting, and constipation -- that tend to accompany opioids like morphine and oxycodone.

While approval of the immediate-release version of tapentadol will certainly produce sales, a long-lasting extended-release version is more likely to deaden the pain associated with the cost of development. That's because it'll be more convenient for patients than the four-to-six-hour dosing the immediate-release version requires.

Bigger is better
Genzyme (NASDAQ:GENZ) isn't trying to get a new drug approved for marketing; it just wants to be able to make its enzyme replacement therapy Myozyme on a larger scale. The FDA wasn't so sure that the new manufacturing setup resulted in the same product, so it punted to a panel of experts last month. The panel voted 16-to-1 to recommend approval if Genzyme runs more clinical trials to prove that the drug is equivalent to the batches produced at the smaller scale.

The interesting thing about this decision is that it has far-reaching consequences beyond Genzyme's one drug. Generic-drug companies like Novartis (NYSE:NVS) and Teva Pharmaceuticals (NASDAQ:TEVA) want to be able to make generic versions of biologic drugs -- like Myozyme -- after they go off-patent. Getting Congress to set up a system for approval similar to the one for small molecule drugs may not be enough. The FDA will ultimately determine whether the generic drugs are identical enough to their branded counterparts to get on the market. If a drugmaker is having trouble convincing the FDA that it can make the same drug at two scales, imagine how hard it'll be for generic-drug makers that are starting from scratch.

Getting back to Myozyme, I think it's likely that the FDA will compromise and approve manufacturing of the drug, but only for adults, leaving the more proven smaller scale available for children until the larger scale is proven effective. With a PDUFA date of Nov. 29 -- the Saturday after Thanksgiving -- it wouldn't surprise me to see Genzyme getting its gross-margin stuffing a little early this year.

Breathing easier
As one of the first benefits from acquiring MedImmune's pipeline last year, AstraZeneca (NYSE:AZN) will get a shot at approval of its respiratory syncytial virus (RSV) prophylactic, motavizumab, around Nov. 30. Unfortunately, the drug, which helps prevent a viral lung infection in infants, might just unseat sales of its current treatment Synagis. In a head-to-head trial, motavizumab seemed to work better than Synagis. This could help it surpass sales of Synagis, which is already a blockbuster with sales of $724 million in the first nine months of the year.

Motavizumab should also help AstraZeneca stay ahead of Alnylam (NASDAQ:ALNY), which is developing an RNAi-based treatment for RSV that has shown initial promise.

Perhaps this article is 90 days too early
It's important to remember that these dates are goals that the FDA sets for itself. Recently, the agency has been missing those targets left and right. Sometimes the delays are announced ahead of time -- Ligand Pharmaceuticals' and Pfizer's (NYSE:PFE) osteoporosis treatment Fablyn has been delayed until January of next year -- and other times companies just sit in deafening silence while they wait for news.

For day traders, that's got to be disappointing, but for Fools it doesn't matter all that much. Pick a good price, assume a delay is inevitable, and confirm that the company has enough cash to deal with the delay. Then sit back and enjoy the gut-wrenching show.