Getting a drug approved may be a marathon, but the battle isn't over when the Food and Drug Administration slaps an approved stamp on the marketing application. Drugmakers still have to get their drug paid for. Lack of coverage by insurance companies or government agencies can severely dampen the potential customer base.

Dendreon's (Nasdaq: DNDN) investors understand that all too well. The company has secured reimbursement from quite a few insurers -- Aetna (NYSE: AET), Humana (NYSE: HUM), Kaiser, and others -- but hasn't landed a final decision from the big Kahuna: Medicare.

Back in July, the Centers for Medicare & Medicaid Services (CMS) announced that it planned on reviewing the reimbursement for Dendreon's prostate cancer treatment Provenge. The process is supposed to take about a year with a proposed decision by March 30, 2011 and a final ruling in June 2011.

That's like 5,768 years in investor time.

Fortunately investors won't have to wait that long to get a good idea on how this might play out. CMS has scheduled a meeting to review the treatment on Nov. 17. A panel of experts will be convened to figure out which patients in the government programs should get the treatment.

I don't think there's any way that CMS issues a ruling that Provenge shouldn't be paid for at all, so we're just talking about the amount of restrictions that should be placed on the reimbursement.

Unlike Johnson & Johnson's (NYSE: JNJ) and Amgen's (Nasdaq: AMGN) anemia drugs that underwent a similar review, we haven't seen new information come to light after the approval. Without any clinical trial data other than what's on the label, the most likely outcome is that the panel recommends limiting the reimbursement to on-label use. Eliminating off-label use would shrink the potential patient population until Dendreon tests the drug on patients earlier in their disease progression, but it wouldn't be disastrous by any means.

The biggest concern that investors should have at this point then is how many hoops CMS might make doctors jump through to get their patients on Provenge. Will signing something saying that the patient matches the label be sufficient or will the agency require proof of medical tests? Restrictions could have some doctors heading toward the competition, sanofi-aventis' (NYSE: SNY) Taxatore, but whether it'll be by any appreciable amount remains to be seen.

Matt Koppenheffer hates this stock, but he's not willing to short it either.