Being a drug-company shareholder before the Food and Drug Administration makes decisions about those companies' drugs can be scary, but it can also lead to spectacular returns. If you have the guts to buy, here are a few drug companies hoping for those kinds of returns next year.

Exubera 2.0?
The biggest hurdle for Mannkind's (NASDAQ:MNKD) inhaled insulin, Afresa, probably won't be getting past the FDA near its PDUFA date of Jan 16. Insulin is a pretty basic drug, and Afresa seems to have a better profile than other options; unlike current offerings, it mimics natural insulin spikes seen in non-diabetics after they eat.

Instead, Mannkind's biggest obstacle will be on the marketing front, keeping from following in the footsteps of Pfizer (NYSE:PFE) and Nektar Therapeutics' inhaled insulin, Exubera. Not too many doctors were exuberant about Exubera; the drug/device registered a measly $12 million in sales during its first nine months on the market before Pfizer gave up and handed the drug back to Nektar.

Afresa is smaller than Exubera, and Mannkind is working on an even smaller device whose size will be a selling point. Ultimately, though, it will come down to whether doctors are interested in trying out a new product when the current offerings work well enough and whether patients request a needle-free alternative.

Mannkind may be able to get some traction, but I expect a slow uptake.

678 fewer injections
Amylin Pharmaceuticals (NASDAQ:AMLN) and Eli Lilly's (NYSE:LLY) Byetta is a great drug. It controls diabetics' glucose well, keeping them from having to go onto insulin. It even has an added benefit of causing weight loss.

The only problem is that the drug has to be injected twice a day. That's fairly burdensome compared with popping pills like Merck's (NYSE:MRK) Januvia, and sales have suffered, reaching only $679 million last year and falling slightly through the first three quarters of this year as some worries of pancreatitis have arisen.

The duo's solution is a once-weekly formula of Byetta using Alkermes' extended-release technology. The decreased injections should increase sales, but first they'll have to get past the FDA in March. The efficacy data looked good -- it beat Januvia and Takeda's Actos in head-to-head trials -- but the FDA may be leery of an approval because of the side-effect issue. Novo Nordisk's once-daily liraglutide, which is in the same class, has been waiting for an FDA approval since last March.

Once-weekly Byetta should be approved, but don't expect a speedy FDA decision.

2 years in the making
After the FDA's somewhat shocking denial of Dendreon's (NASDAQ:DNDN) prostate-cancer treatment Provenge in May of 2007, the company will have another date with the FDA on May 1 of next year.

The data the FDA previously requested turned out positive, so an approval seems more likely than not. The biggest risk is that the FDA finds something wrong on the manufacturing side of things. The treatment takes immune cells from a patient and trains them to become cancer-fighting machines before putting them back into the patient. The FDA needs to be certain that Dendreon can accurately repeat the process.

Here's hoping that Dendreon doesn't end up sending out another mayday to investors on May Day.

Potential obesity-drug approvals: size XXXL
2010 could see the FDA weighing in on three obesity drugs. Arena Pharmaceuticals and VIVUS (NASDAQ:VVUS) both submitted their applications to the FDA this month, and Orexigen Therapeutics expects to file in the first half of next year.

Of the three, VIVUS' Qnexa probably has the best weight-loss data, but Arena's Lorcaserin may have the best safety profile. The latter is important, since diet and exercise work pretty well as treatments for obesity and the agency is likely to be very safety conscious. An approval for any or all of the drugs isn't a slam dunk, but considering the large market, the risk could be worth the reward.

Usual disclosures apply
Keep in mind that the FDA sets up PDUFA dates, but they're not a deadline that the agency is required to meet. Trying to day-trade around the PDUFA date can be dangerous to your portfolio. A much better strategy is to think longer-term. Find a company you like at a price you can live with, and don't worry about any delays the FDA may throw at your investment.

Any other FDA decisions you're looking forward to in the new year? Let us know in the comment box below.

Pfizer is a Motley Fool Inside Value choice. Novo Nordisk is a Motley Fool Global Gains selection. Try any of our Foolish newsletter services free for 30 days.

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