It's on. Since the government didn't shut down, the Food and Drug Administration is working at full steam, including hosting experts at an advisory panel meeting tomorrow.

Pfizer (NYSE: PFE) and Novartis (NYSE: NVS) might just as soon done it another day.

The FDA briefing documents for the committee released Friday were less than kind to the drugmakers. Both Pfizer's Sutent and Novartis' Afinitor are up for review as treatments for pancreatic neuroendocrine tumors.

Pfizer's Sutent had amazing results in the rare tumor type, but the agency is worried that the clinical trial results may overstate the benefit. The trial was stopped early because the drug was working so well -- it's not ethical to treat cancer patients with placebo when there's a drug that works. But stopping the trial early means there's a limited number of patients upon which to base the magnitude of the effect. 

For Novartis, problems stem from a trial testing Afinitor in related cancers, which failed to show an effect. The drugmaker dropped its application to market the drug for those types of cancers, but the FDA is puzzled as to why the drug should work for pancreatic neuroendocrine tumors, but not related tumors.

Both Sutent and Afinitor are already on the market. Sutent is approved for kidney cancer and a type of gastrointestinal tumor. Afinitor is used after Sutent or Nexavar from Bayer and Onyx Pharmaceuticals (Nasdaq: ONXX) in kidney cancer patients and is also approved to treat a rare brain tumor.

Doctors can prescribe the drugs off label for pancreatic neuroendocrine tumors, but gaining approval will allow the companies to market the drugs for the tumor type as well as make insurance reimbursement easier.

Frankly, I'm a little surprised at the FDA's glum view of the drugs, especially Sutent, considering the unmet need of patients with pancreatic neuroendocrine tumors. The company's best hope is that the experts on the panel recognize that, but keep in mind that their vote is only advisory and the FDA has the final say.

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